Assembly lube summary


Well-Known Member
Maybe I missed it on the forum but is there a list describing what type of assembly lube to use and where, when building an engine? While doing research on this site and reading through a few engine build books, here’s what I have been able to determine. Am I missing anything?
Crank, main/bearings, rod journal/bearings and piston pin - For pre-assembly and checking clearances use engine oil. For final assembly, use a good moly based assembly lube. Mix moly based assembly lube with a little engine oil for easer application.

Cylinder bores – Engine oil or Marvel Mystery Oil.

Pistons – Dip in engine oil or Marvel mystery oil prior to installation

Valve train including push rod ends, rockers and valve stems – Moly assembly lube

Cam bearings and thrust bearing/plate – Moly assembly lube

Timing chain – Soak in engine oil and moly assembly lube mixture prior to installation

Lifters - Follow manufacture’s install and break-in instructions

Camshaft – Follow manufacture’s install and break-in instructions
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you seem to have a good basic understanding

cleaning threads before assembly is always a good idea

check manufactures tech guide info

having consistent clamp loads are mandatory for proper assembly

keep in mind the assembly lube or even oil on the bearing surfaces has a surface shear limit,
that why the crank is harder to start rotating but the required effort to keep it spinning is significantly lower,
your initial effort to twist the crank must break that surface tension on the lube,
once its sheared the lube forms a lubricating layer and metal to metal contact is prevented as the lube forms a barrier layer











moly spray on the bore surfaces doesn,t hurt either

read these links ... -lube.html
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Home Blog Default Moly Basics
Moly Basics
Molybdenum Disulfide

Molybdenum is a very hard metal with a number of industrial uses.
It is combined with chromium in steel to make the steel harder and more resistant to bending. Most of the bicycle frames produced today use chromium and molybdenum steel. Because the steel is so much harder, the manufacturers can use less, thereby making the frame lighter.

Molybdenum Disulfide (Moly) has been used for decades in lubricating pastes and greases because it is slippery and forms a protective coating on metal parts.

Moly exists as microscopic hexagonal crystal platelets Several molecules make up one of these platelets. A single molecule of Moly contains two sulfur atoms and one molybdenum atom. Moly platelets are attracted to metal surfaces. This attraction and the force of moving engine parts rubbing across one another provide the necessary thermochemical reaction necessary for Moly to form an overlapping protective coating like armor on all of your engine parts. This protective armor coating has a number of properties that are very beneficial for your engine.


The Moly platelets that make up the protective layers on your engine surfaces slide across one another very easily. Instead of metal rubbing against metal, you have Moly platelets moving across one another protecting and lubricating the metal engine parts.

This coating effectively fills in the microscopic pores that cover the surface of all engine parts, making them smoother. This feature is important in providing an effective seal on the combustion chamber. By filling in the craters and pores Moly improves this seal allowing for more efficient combustion and engine performance.

This overlapping coating of Moly also gives protection against loading (perpendicular) forces. These forces occur on the bearings, and lifters. The high pressures that occur between these moving parts tend to squeeze normal lubricants out.

Eventually, there is metal to metal contact, which damages these moving parts and creates large amounts of heat. Fortunately, this is not the case with some lubricants.The layer of moly that forms on these moving surfaces can withstand pressures of 500,000 psi, without being squeezed out.

Engineers and scientists have tried for years to use Moly in motor oils but they had been unsuccessful because they could not find a way to keep Moly in suspension. Once Moly was put into suspension it would gradually settle out. It was easy to see it come out of suspension because a black sludge would collect on the bottom of the oil containers. In engines it would settle to the bottom of the crankcase or clog oil pathways and filters.

Engineers have overcome these obstacles. They have developed a process that keeps Moly in suspension and isn’t filtered out. Since that time theproduct has undergone extensive independent testing in labs and in the field for many years to insure that the product stands up to the rigorous needs of today’s engines. With the plating action of Moly reducing friction which reduces heat, this helps keep rings free from carbon buildup, prevents blow-by, decreases emission, and extends oil life.

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What is Molybdenum Disulfide and why is it showing a good lubricating behavior?

Molybdenum Disulfide, also known as Molybdenum Disulphide, MoS2 and Moly, is one of the most widely used solid film lubricants. Like graphite and tungsten disulfide (WS2), MoS2 is a dichalcogenide. The lubricating properties of molybdenum disulfide lubricant are due to a weak atomic interaction (Van der Waals Force) of the sulfide anions, while the covalent bond within the molybdenum is strong.
Which are the easiest and widely recognized ways of applying MoS2 coating?

There are a number of ways to apply MoS2 low friction coatings to the desired substrate. These include:

Rubbing and burnishing
Impingement with or without inorganic binder
Spraying or dipping paint like substance containing the molybdenum disulfide as a lubricant
Physical vapor deposition

Some of the specifications covering this application are; MIL-PRF-46010, AS5272, AMS2526.
Why molybdenum disulfide coating is considered unbeatable in comparison to its competitors?

In moving/mating components, friction causes considerable loss of energy, poorer performance, and limits the wear life of the components. Molybdenum Disulfide can provide a low coefficient of friction, sometimes as low as 0.05 COF. This will be dependent on the humidity, cleanliness, and sliding conditions of your application.

Also molybdenum disulfide dry lubricant can:

Operate in a wide range of temperatures up to 600 deg F and maintain its lubricity in high load, high speed conditions.
Be very effective in inhibiting corrosion as well when combined with the proper resins and binders.

Lubrication relies on the slippage along the sulfur atoms. All of the properties of the lamella structure are intrinsic and no external form of moisture is required (as it is with graphite). Mos2 performs best when water vapor is not present, making molybdenum disulphide coating ideal for vacuum applications. ... 2-3-1.aspx

Was wondering what a Lamella Structure was about and came across this article.

Solid Lubricants / Dry Lubrication

Graphite and molybdenum disulfide (MoS2) are the predominant materials used as solid lubricant. In the form of dry powder these materials are effective lubricant additives due to their lamellar structure. The lamellas orient parallel to the surface in the direction of motion.

Even between highly loaded stationary surfaces the lamellar structure is able to prevent contact. In the direction of motion the lamellas easily shear over each other resulting in a low friction. Large particles best perform on relative rough surfaces at low speed, finer particle on relative smooth surface and higher speeds.

Other components that are useful solid lubricants include boron nitride, polytetrafluorethylene (PTFE), talc, calcium fluoride, cerium fluoride and tungsten disulfide.

Typical applications
Molybdenum Disulfide
Boron Nitride
Application Methods
Self lubricating composites

Typical applications

Solid lubricants are useful for conditions when conventional lubricants are inadequate.

reciprocating motion. A typical application is a sliding or reciprocating motion that requires lubrication to minimize wear as for example in gear and chain lubrication. Liquid lubricants will squeezed out while solid lubricants don't escape and prevent for fretting corrosion and galling.
ceramics. Another application is for cases where chemically active lubricant additives have not been found for a particular surface, such as polymers and ceramics.

high temperature. Graphite and MoS2 exhibit high temperature and oxidizing atmosphere environments, whereas liquid lubricants typically will not survive. A typical application include fasteners which are easily tightened and unscrewed after a long stay at high temperatures.

extreme contact pressures. The lamellar structure orient parallel to the sliding surface resulting in high bearing-load combined with a low shear stress. Most applications in metal forming that involve plastic deformation will utilize solid lubricants.


Graphite is structurally composed of planes of polycyclic carbon atoms that are hexagonal in orientation. The distance of carbon atoms between planes is longer and therefore the bonding is weaker.

Graphite is best suited for lubrication in a regular atmosphere. Water vapor is a necessary component for graphite lubrication. The adsorption of water reduces the bonding energy between the hexagonal planes of the graphite to a lower level than the adhesion energy between a substrate and the graphite. Because water vapor is a requirement for lubrication, graphite is not effective in vacuum. In an oxidative atmosphere graphite is effective at high temperatures up to 450ºC continuously and can withstand much higher temperature peaks. The thermal conductivity of graphite is generally low ~1.3 W/mK at 40ºC.

Graphite is characterized by two main groups: natural and synthetic. Synthetic graphite is a high temperature sintered product and is characterized by its high purity of carbon (99.5-99.9%). The primary grade synthetic graphite can approach the good lubricity of quality natural graphite.

Natural graphite is derived from mining. The quality of natural graphite varies as a result of the ore quality and post mining processing of the ore. The end product is graphite with a content of carbon (high grade graphite 96-98% carbon), sulfur, SiO2 and Ash. The higher the carbon content and the degree of graphitization (high crystalline) the better the lubricity and resistance to oxidation.

For applications where only a minor lubricity is needed and a more thermally insulating coating is required, then amorphous graphite would be chosen (80% carbon).

Molybdenum Disulfide

MoS2 is a mined material found in the thin veins within granite and highly refined in order to achieve a purity suitable for lubricants. Just like graphite has MoS2 a hexagonal crystal structure with the intrinsic property of easy shear. MoS2 lubrication performance often exceeds that of graphite and is effective in vacuum as well whereas graphite does not. The temperature limitation of MoS2 at 400ºC is restricted by oxidation. The particle size and film thickness are important parameters that should be matched to the surface roughness of the substrate. Large particles may result in excessive wear by abrasion caused by impurities in the MoS2, small particles may result in accelerated oxidation.

Boron Nitride

Boron Nitride is a ceramic powder lubricant. The most interesting lubricant feature is its high temperature resistance of 1200ºC service temperature in an oxidizing atmosphere. Further Boron has a high thermal conductivity. Boron is available in two chemical structures, i.e. cubic and hexagonal where the last is the lubricating version. The cubic structure is very hard and used as an abrasive and cutting tool component.


PTFE is widely used as an additive in lubricating oils and greases. Due to the low surface energy of PTFE, stable unflocculated dispersions of PTFE in oil or water can be produced. Contrary to the other solid lubricants discussed, PTFE does not have a layered structure. The macro molecules of PTFE slip easily along each other, similar to lamellar structures. PTFE shows one of the smallest coefficients of static and dynamic friction, down to 0.04. Operating temperatures are limited to about 260ºC.

Application methods

Spraying/dipping/brushing: Dispersion of solid lubricant as an additive in oil, water or grease is most common used. For parts that are inaccessible for lubrication after assembly a dry film lubricant can be sprayed. After the solvent evaporates, the coating cures at room temperature to form a solid lubricant. Pastes are grease like lubricants containing a high percentage of solid lubricants used for assembly and lubrication of highly loaded, slow moving parts. Black pastes generally contain MoS2. For high temperatures above 500°C pastes are composed on the basis of metal powders to protect metal parts from oxidation necessary to facilitate disassembly of threaded connections and other assemblies.

Free powders: Dry-powder tumbling is an effective application method. The bonding can be improved by priory phosphating the substrate. Use of free powders has its limitations, since adhesion of the solid particles to the substrate is usually insufficient to provide any service life in continuous applications. However, to improve running-in conditions or in metal forming processes a short duration of the improved slide conditions may suffice.

AF-coatings: Anti-friction coatings are "lubricating paints" consisting of fine particles of lubricating pigments, such as molydisulfide, PTFE or graphite, blended with a binder. After application and proper curing, these lubricants bond to the metal surface and form a dark gray solid film. Many dry film lubricants also contain special rust inhibitors which offer exceptional corrosion protection. Most long wearing films are of the bonded type but are still restricted to applications where sliding distances are not too long. AF-coatings are applied where fretting and galling is a problem (such as splines, universal joints and keyed bearings), where operating pressures exceed the load-bearing capacities of ordinary oils and greases, where smooth running in is desired (piston, camshaft), where clean operation is desired (AF-coatings will not collect dirt and debris like greases and oils), where parts may be stored for long periods of time.


Self lubricating composites: Solid lubricants as PTFE, graphite, MoS2 and some other anti friction and anti wear additives are often compounded in polymers and all kind of sintered materials. MoS2 for example is compounded in materials for sleeve bearings, elastomere O-rings, carbon brushes etc. Solid lubricants are compounded in plastics to form a "Self lubricating" or "Internally lubricated" thermoplastic composite. PTFE particles for example compounded in the plastic form a PTFE film over the mating surface resulting in a reduction of friction and wear. MoS2 compounded in Nylon reduces wear, friction and stick-slip. Furthermore it acts as a nucleating agent effecting in a very fine crystalline structure. The primary use of graphite lubricated thermoplastics is in applications operating in aqueous environments.



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BTW Ive seen guys advise the use of lithium axle grease as bearing assembly lube on cams, lifters rockers and bearings occasionally, at times , this is VERY BAD ADVICE , ITS SIMPLY the wrong lubricant to be used, when guys substitute white lithium bearing grease for moly assembly lube, (white lithium bearing grease) is generally not automotive oil soluble,its a soap base grease, that clumps up like old peanut butter in the oil pan, and it quickly plugs oil passages, in lifters and, clogs filter mediums in oil filters, and can and does completely clog shrapnel screens causing oil to, fail to drain back into the oil pan sump, and it can and will clog oil pump pick-up screens

ASSEMBLY LUBE USED ON CAMS AND LIFTERS ROCKERS< BEARINGS ETC. like CRANE CAM LUBE, has molybdenium disulfide in assembly lube, that helps maintain a strong heat resistant high pressure lubricating support film on sliding surfaces, BUT assembly lube is NOT INTERCHANGEABLE WITH MOLY AXLE GREASE
which has other ADDITIVES, in some cases its mixed with non-compatible lithium grease base,
you must use a moly based assembly lube thats designed to mix with automotive oil to provide a strong surface film on sliding surfaces



The Moly platelets that make up the protective layers on your engine surfaces slide across one another very easily. Instead of metal rubbing against metal, you have Moly platelets moving across one another protecting and lubricating the metal engine parts.


MOLY adds a great deal of lubrication to sliding metal surfaces , as it embeds in the micro fissures in the metallic surface's


This coating effectively fills in the microscopic pores that cover the surface of all engine parts, making them smoother. This feature is important in providing an effective seal on the combustion chamber. By filling in the craters and pores Moly improves this seal allowing for more efficient combustion and engine performance.

This overlapping coating of Moly also gives protection against loading (perpendicular) forces. These forces occur on the bearings, and lifters. The high pressures that occur between these moving parts tend to squeeze normal lubricants out.
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ALLEN said:
,Grumpy my local machine-shop swears that kendal blue bearing grease


is the best assembly lube available, what do you think??

its not designed to be 100% compatible with the conditions prevelent in a running engine ,nor is it easily dissolved and mixed with hot engine oil, or designed to run through an oil filter
Hes, using it probably because it cost 1/8th of what CRANES MOLY BREAK-IN GREASE COSTS

If your going to use a grease to protect bearings during the engine assembly process, it must be 100% compatible with engine oil, and easily flow through an oil filter mixed with oil, something axle bearing grease was never intended to do!

ID suggest use of a 50% /50% mix of
MMO and CRANES MOLY cam lube like Ive used for decades,its easily mixed with engine oil and flows easily through an oil filter as the micro moly lubricant particles are far smaller than the filter pores.
as its designed to mix with engine oil and provide a micro moly film on surfaces,


pre-oiling the rockers before starting an engine the first time helps prevent problems

the blue trailer bearing grease is
Lithium Complex , I looked up the spec sheet, on KENDAL OIL,
and no where does it mention it mixes well with engine oil,
or that its recommended for use in engine bearings,
while it may "work" ID suggest NOT using it,
or at least calling and talking to kendals engineering staff,
about its use in that application.

Kendall L-427 Super BLU-Grease
Multi-Purpose, Extreme Pressure Lithium Complex Grease

Product Data Sheet and MSDS


Multipurpose, Extreme Pressure Lithium Complex Grease; NLGI GC LB Certified. Kendall® L-427 Super Blu Grease is a high-quality, multipurpose, extreme pressure (EP) lithium complex grease developed to satisfy the severe lubrication requirements of heavily-loaded plain and rolling-element bearings operating at moderate to high temperatures. It is NLGI GC-LB certified for use as a multipurpose automotive wheel bearing and chassis lubricant. L-427 Super Blu Grease is manufactured with high-quality paraffinic base oils thickened with a lithium complex soap. It contains an extreme pressure additive, a tackifier, and rust and oxidation inhibitors to provide excellent wear protection, excellent thermal stability at high temperatures, and excellent resistance to corrosion and water washout. It forms an effective seal to help minimize bearing contamination and provides a high level of adhesion to the bearing surface for improved retention, reduced leakage and enhanced resistance to water washout.


  • Excellent performance over a wide temperature range.
  • Excellent wear protection.
  • High load-carrying capacity.
  • Protects against rust and corrosion.
  • Excellent resistance to water washout.
  • NLGI GC-LB certified.


Wheel bearings on passenger cars, light trucks, high-performance vehicles, sport utility vehicles and motorcycles with disc brakes, ball joints, universal joints, other chassis parts and water pumps on passenger cars, trucks and other mobile equipment, pl
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Perhaps the most important property of lube oil is its ability to remove heat from a surface where two or more metals are sliding across each other. In much the same way as air flows around cylinder head fins to remove heat, oil flows through a bearing and removes the heat caused by friction. I can’t imagine the destruction which would follow from assembling an engine completely dry.

A thin coating of assembly lube should be applied on all high-friction, high-load surfaces including rod, main and cam bearings.
Assembly Lubes

Assembly lubes are one of the most important parts of an engine build. But, some components are hard to lubricate prior to start-up, and other parts allow assembly oils to drain off during storage. Let’s address the best way to overcome both of these problems.

Prior to learning about greases, I used a mixture of SAE 30 grade motor oil and STP on my engine builds. I put that very stiff goo on everything from rod and main bearings to pushrod tips. The engines I built using this technique were often very hard to turn over fast enough to start in the days before gear-reduction starters.

Then I learned to use my head for something other than a hat rack. Most engine builders (other than the fueler gang) pre-lube their engines by either pressurizing the oil galleys or spinning the oil pump until sufficient oil pressure is achieved. This means builders can use oils similar in viscosity to the oils they would actually operate their engines on. Hard engine turnover problem solved.

But what about those engine components not directly lubricated by engine oil pressure? Camshaft lobes, flat tappet lifters, and pushrod tips are lubricated only by splash after the engine is running. One can use oil to lubricate these parts prior to startup, but what about long-term storage?

Long-term storage can allow oil to run off these parts over time. But if we think about it, grease is merely a mixture of oil with what chemists would refer to as a soap substrate. Grease is designed to hold the oil in suspension until sufficient heat or motion builds up to release the oil and allow it to do its job. Grease is the perfect solution to stop run off.

From that day forward I’ve used high performance engine oil to lubricate all engine components except flat tappets, cam lobes and valve train components when assembling an engine. I even use oil on the cam bearings and journals, but on the cam lobes, flat tappet lifters and pushrod tips I use grease. You don’t have to use grease on cam lobes and roller lifters, because roller lifters don’t slide across the cam lobe. I’ve had zero failures since I learned to use grease.

Fueler racers use very heavy oil (60 or 70 grade), grease, or a newly developed gel on their engine components, because they just don’t have sufficient time between engine rebuilds in the pits. Besides, those hand-held starters deliver a lot more torque than smaller, gear-reduction starters.

However, I’ve learned something very important about which properties you must have in the grease you utilize. First, the grease must be oil soluble. If you use a grease like a white paste many people used years ago, you will find this material is not oil soluble, and you will plug oil filters with a white residue. That’s okay if you remember to change oil filters immediately after the engine is run for a few minutes, but I like things to be automatic so I don’t have to rely on my faulty memory.

Secondly, it’s a good idea to use extreme pressure (EP) grease, particularly when you have high lift cams and very stiff valve springs. Some greases just don’t have the film strength to protect components where the contact area is limited (like pushrod or valve tips). Even lifter contact takes place over an area much smaller than you would think. So I prefer to use EP grease all the time; it’s just cheap insurance.

Another area which needs to be addressed is the use of lubricants to properly torque head and rod bolts. Since this is a very involved discussion, I’ll save it for a subsequent article. There are some very important things to consider about torqueing bolts.

Some assembly lubes have a paste-like consistency and are applied with a brush while others are more like honey and can be applied from a squirt bottle.
Break – In Oils

I recall building an engine with chrome rings back in the ‘60s. I couldn’t get a decent break-in in spite of everything I did. I couldn’t figure it out, so I quit using chrome rings.

Then in the early ‘80s Daimler-Benz was using a very high-quality, high-TBN diesel engine oil as factory fill in all their engines to enable oil change intervals as high as 100,000 kilometers. They contacted us because these engines were burning excessive oil for many thousands of miles, and many customers were demanding expensive rebuilds prior to the warranty period expiring.

After considerable engine and field testing we discovered the high TBN diesel oil was preventing sufficient cylinder liner and piston ring wear to break the cylinders in. The harder piston rings, combined with the centrifugally cast alloyed cylinder liners and the excellent diesel oil had reduced wear to the point that some of these engines took over 50,000 miles to fully break in.

This is unacceptable, so we investigated the problem. We found that most wear in the piston ring/cylinder wall regime was caused by chemical corrosion, not lack of EP protection. But good EP protection was still necessary to prevent valve train failures during the break-in period. We then formulated a Daimler-Benz first-fill break-in oil, which had lower levels of detergency yet adequate ZDDP levels to protect valve train components. Problem solved.

Years later, I was talking with the head engine builder at Richard Childress Racing, and he stated that good, quick cylinder sealing was very important to his NASCAR engines. We drew upon our Daimler-Benz experience to formulate a low detergent, high ZDDP break-in oil for him to evaluate. Since automotive engine oils often contain friction modifiers, we also looked at the effect on break-in rate. Our resultant recommendation contained increased ZDDP, low levels of detergent, and no friction modifiers. The results were impressive, and he was very happy.

So what did we learn? It is imperative that the piston rings and cylinder walls quickly wear to the point that cylinder pressure leakage is minimal. Break-in oils can speed this process significantly over fully formulated automotive or racing engine oils.

This concept has been both dyno and field tested many times, and results have always been better than when using typical engine oils.


I keep a large container of break-in oil and a smaller container of EP grease in my shop at all times. Even though I once fired up an engine without an oil pump pressure relief valve installed, I’ve never suffered a failure due to lack of lubrication. The mixture of assembly lube and grease has always protected valuable engine components until the engine could be safely broken in.

In the October 2012 issue of Engine Builder, I wrote about engine assembly lubes and why you should consider using them. When I was asked to write another article to help engine builders better understand and select engine assembly lubes for their operation, at first I didn’t understand the assignment.

I thought I had explained everything in the previous article. But after a visit to a popular parts retail website that showed me 85 separate listings under engine assembly lubes from over 25 suppliers, I began to understand why engine builders are having trouble selecting these products!

For this article, I will try to help you make better informed decisions when choosing assembly lubes and lubricants. First, do you need engine assembly lubes at all? As a physicist-motorhead who has built and destroyed his share of engines, I think so.

When metal-to-metal contact occurs in an engine, localized overheating is created. This can wipe a bearing almost instantly. There are other areas in an engine (e.g., push rod tips, rocker arms) that don’t receive lubricant until a few seconds after the engine has been running and oil spray is established.

As far as lubrication goes, any reasonable amount of oil will protect surfaces by preventing metal-to-metal contact if it contains sufficient Zinc dithiophosphate (ZDP). Thinner oils can rapidly run off the surfaces they are intended to protect. Heavier oils run off more slowly, so they are more effective if the engine is to be stored before use. Today’s passenger car and truck oils don’t contain sufficient (ZDP) to protect parts which haven’t yet been broken in.

The ultimate, of course, is grease. Grease is simply oil which is contained in a waxy, soap substrate. The substrate keeps the oil from running away until it is needed. When operating temperatures rise, the substrate melts, and the oil flows to the component to do its job.

Don’t use grease on every part of the engine because it is so stiff that it will make that first start difficult. Use grease only where oil flow and surface protection is less than desirable such as:

• Blower drive gears

• Camshaft gear drives

• Flat tappet cams and lifters

• Distributor drive gears

• Pushrod tips

• Rocker arm and valve stem tips

Although I’m a fan of using grease where it’s needed and heavy oil everywhere else, I did experience something scary about some greases. Some greases do not dissolve in oil. I was at a NASCAR shop when they fired up a new engine. After a brief break-in regimen, the dyno operator took the Oberg apart to look for engine damage. There were small, white particles all over the surface of the Oberg screen. From then on I’ve insisted on using assembly greases that dissolve in oil.

Those particles floating around in the engine make me nervous. What if one of them blocks an oil feed hole? One doesn’t have to gamble, since most greases out there dissolve in oil. Be sure to ask your supplier that direct question.

If the engine will be fired up and broken in immediately, then heavy oil, STP, or a mixture of heavy oil and STP (with adequate ZDP) will probably give adequate protection. Before engine assembly lubes were invented, I used a mixture of STP and SAE 30 grade oil plus added ZDP as an engine assembly lube. Back then I still used grease on flat tappet cams and lifters.

The problem with heavy oils and STP is they weren’t formulated to be engine assembly lubes. New Shell Rotella, for example, contains less than 0.01% weight zinc. I like to see at least 0.02% zinc for initial startup. They will work, but chemically engineered engine assembly lubes contain ZDP chemistry for extreme pressure (EP) protection and rust inhibitors to prevent rusting of vital components. Rust on a valve spring can significantly affect its elastic limit or even cause it to break under extreme circumstances. Tackifier agents are also used in assembly lubes to help the oil cling to the surface to be protected longer.

None of the above will protect an engine if it is put together dirty. We mentioned that last time, but any speck of material which is harder than cast iron and larger than the bearing clearances can easily destroy the perfect engine build. Engine components can’t be cleaned too much before putting the engine together. I clean my blocks in soap and water and then spray them down with WD-40 in hopes of removing all potentially dangerous particles which might be embedded in the porous cast iron or aluminum. I clean lifters and rocker arms in solvent to remove machining debris, blow them dry, and then soak them in break-in oil.

I’ve also begun using fluids on bolts which are to be torqued. ARP started this trend, and I agree with them. Using a lubricant on a bolt does two things. First, lubricating the threads means the bolt will pull down more evenly with less stiction. Secondly, a lubricated set of threads means a bolt will be pulled down tighter at the same torque wrench reading (more bolt stretch), because friction between the threads has been significantly reduced.

I should also comment about GM E.O.S. as a lubricant supplement. E.O.S. was originally designed to add more ZDP and other additives to ’60s design oils which weren’t very heavily compounded. Oils of today have two to three times the additive content of 1960s oils, with the exception of ZDP. The only thing they need to be more effective is additional ZDP, rust inhibitors, and tackifiers. I’m not certain E.O.S. is the best answer for today’s engines and oils.

This brings up the subject of brand marketing. We all experience it every day, and it upsets an old technical guy like myself. Just because your grandfather ran a specific brand of oil that was great once upon a time doesn’t guarantee that it is great now. The Gulf Oil Co. hasn’t existed for many years, yet the brand name is still out there owned by two current oil marketers.

Lube specifications, lubricant formulations, additive suppliers, and the resultant products change every few years. Marketers promote brand names hoping you will be lazy and merely trust that brand name to protect your engine forever! However, as a scientist, I want to see actual test data, not testimonials from Joe Sixpack prior to making purchases. And scantily-clad ladies don’t necessarily know much about engine lubes!

Therefore, how does one intelligently decide which assembly products to use? I’m going to ignore roller cams here, because rollers don’t have the EP requirements that flat tappet cams do. Rollers just need adequate, clean oil to allow their components to survive. Never use grease on rollers. If that roller skids across the cam lobe a few times without turning, it can flat spot and fail.

I recommend selecting an oil-soluble grease for use on cam lobes and lifters of flat tappet cams. Request that the various suppliers provide performance data. Use the grease you selected on all the components I mentioned above. Then if the engine has to set for a while, you’re covered. I can’t recommend brand names here, because I helped invent some of the products out there.

Then I would select a heavier viscosity oil (e.g., 20w50), oil assembly lube, break in oil, or hot rod oil to put on all the bearing surfaces, rocker arms, etc. Don’t forget to put oil in the pan, so the engine isn’t accidentally started up dry. Some oil assembly lubes, break-in oils, and hot rod oils contain a vapor phase rust inhibitor that will protect stored engines longer. I prefer using these oils because they are safer for use if your engine won’t be fired up immediately. Don’t forget to oil the crankshaft seals to prevent them from tearing on start-up.

I use a thinner mineral oil (SAE 10w30 or 10w40), not a synthetic, on cylinder walls and piston rings. These areas don’t need as much EP protection – you actually want the piston ring face and cylinder walls to have accelerated wear at startup to better seat the rings, thereby optimizing their ability to seal combustion pressures. You can even use a little oil on cylinder walls and no oil on the rings, but I like to be conservative.

I hope this discussion helps unshroud some of the mysteries about engine assembly lubes. You don’t need to take any more chances with an engine build than you have to.

John Martin is a “motorhead” physicist who worked for Lubrizol for 25 years, and before that he worked for Shell. He has formulated and tested racing oils for NASCAR and NHRA Pro Stock engines for decades.

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most flat tappet cams use 110 lb-130 lb seat pressure springs ,
you can get by with the 140 lb-150 lb seat pressure springs in almost every application,
with a roller lifter cam, IF ITS A HEAT TREATED SURFACE HARDENED cam
but I would have suggested swapping to a billet cam by the time the seat pressure was much over 150 lbs
as the pressure on the lifter roller wheel increases so does the potential for having issues if you match a roller lifter and a soft cam lobe.
very good


very very good


btw I got asked how I apply the 50%/50%
I generally spray crank journals and bearing surfaces with moly spray first , then paint on the mix linked below.
Preference on assembly lube?

50% marvel mystery oil


and 50% crane moly lube, or the paste moly, the mix of moly paste and M.M.O. is generally applied liberally with the paint brush in multiple applications to surfaces like cam gears timing chains, lifters rockers and cam lobes to provide an extra layer of lubrication protection on initial engine start up.

what Ive used for decades
but this works


I have used J&B WELD EPOXY on a large magnet

on the base of an aluminum 1/2 cup measuring cup I purchased at a yard sale for 25 cents to mix up the mixture, the magnet allows me to stick the cup to the block oil pan rail or engine stand where its handy too get at, and I simply brush on the mix with a 1" paint brush, with synthetic bristles that won,t shed

slide it off the block don,t try to just pull it off , its going to be much less messy that way trust me!
when your done , wipe it clean and stick it inside the lid of your tool box , after placing it in a ziploc bag to prevent it from picking up trash while in storage


btw that innitial resistence ,too rotation, to get the crank assembly rotating in the bearings and rings dragging accross the cylinder bore surfaces,
as the parts come up on the combined, wedge/lubricant bearing surfaces ,
when it breaks loose and spins easier, is closely related to and changes with the type of assembly lube you selected to use.
the components sellected and clearances and contact surface smoothness and consistency,
every assembly will have minor differences, as will every different lubricant, even temperature will change the results.

that's why you'll need a torque beam deflection torque wrench to check that


the plews 50-347 I bought last year at that auto parts store, is still working fine so for the $15 I paid its been worth the price

OH! in case your curious
I own TWO now , I bought a second one several month later, too use for cutting oil when I use the MILLING MACHINE or DRILL PRESS
as MMO, works buts its not ideal cutting oil for drill bits and end mills
plewsoilC.jpg ... r+drilling


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