engine water pumps

Discussion in 'Cooling Systems' started by grumpyvette, Nov 29, 2008.

  1. grumpyvette

    grumpyvette Administrator Staff Member

    be aware that chevy small block water pumps can be either standard or reverse rotation designs, the 1984-91 corvettes use a reverse rotation pump.this allows the fan belt powering the water pump to travel in either direction provided the correct matching water pumps used, this DOES NOT change the direction of coolant flow in the engine block which in the standard small block chevy enters the front of the engine block , then travels to the rear and up into the cylinder heads then back to the radiator thru the intake manifold thermostat, into the upper radiator hose
    THE LT1 or second design water pump pushes the coolant into the cylinder heads where its eventually forced down thru holes in the lower cylinder heads back into the block and back to the water pump, never flowing thru the intake manifold, on an LT1 the upper radiator hose exits the water pump.
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    ON MOST CHEVY WATER PUMPS COOLANTS DRAWN FROM LOWER RADIATOR HOSE TO THE CENTER AREA OF THE WATER PUMP WHERE IT ENTERS BEHIND THE IMPELLER, THE SPINNING IMPELLERS BLADES INDUCE INERTIAL LOADS DUE TO CENTRIFUGAL FORCE ON THE TRAPPED COOLANT TOO THE OUTER DIAM. EDGE OF THE IMPELLER, ON THE OUTER DIAMETER SIDE IS AN EXIT PORT TO DIRECT LOW PRESSURE COOLANT FLOW OUT OF THE PUMP,INTO THE BLOCK
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    http://www.daycoproducts.com/daycoweb.n ... gGuide.pdf
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    http://www.kwikperf.com/bbc_serp_kit.html

    http://vintageair.com/DownloadsSection/ ... net%29.pdf

    now THATS A VERY USEFUL LINK!


    http://www.stewartcomponents.com/index. ... path=60_66

    http://www.circletrack.com/enginetech/c ... index.html

    viewtopic.php?f=57&t=74&p=674#p674

    http://store.summitracing.com/egnsearch ... wordSearch

    http://store.summitracing.com/partdetai ... toview=sku

    http://www.corvettefever.com/techarticl ... index.html

    http://www.zip-corvette.com/Zip/product ... E93AE993E8

    http://www.cruisecooler.com/FAQs.html

    http://www.who-sells-it.com/cy/holley-p ... -9381.html

    http://store.summitracing.com/egnsearch ... toview=sku

    http://www.corvetteflorida.com/forums/s ... hp?t=26347

    http://www.flowkoolerwaterpumps.com/sto ... index.html

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    keep in mind theres theres BOTH
    iron and steel water pump designs,
    standard and high flow designs,
    BOTH clockwise and COUNTER clockwise rotation,
    long and short designs and at least two,
    a 5/8" and 3/4" dia center axle size
    that the pullies need to match.



    Running straight water in your corvettes in theory cools the engine better, because It transfers heat more efficiently BUT...straight water acts like the acid in a battery and greatly increases corrosion,it effectively causes electrolysis and that will destroy the aluminum in the cooling system very very quickly. As electricity flows thru the block the charge travels thru the water and this allows electrons from the aluminum to be carried away with it in a chemical reaction driven by the electrical charge. The end result is an aluminum head, intake and water pump that has the water passages will be eaten thru like someone poured acid in the cooling system.....There will be pits and holes at random spots where ever there is aluminum in contact with coolant. The solution is a zinc or magnesium anode to take the abuse of the electricity much like the zinc blocks that are mounted on the hull of a ship for the same reason. There are zinc anodes that can be attached to radiator caps that drop in the radiator for those that want that extra oz of protection against electrolysis. The use of the proper mix of anti-freeze & water slows or prevents this chemical/electrical process from taking place. The only other concern is the age of the anti-freeze as that anti-freeze eventually turns acidic over time.
    ALWAYS use an ANODE in the block and at least 40% antifreeze to reduce corrosion, water cools slightly better but its electric conductivity tends to allow corrosion problems that are greatly reduced with antifreeze and an anode installed

    better quality metal flex fans, when properly matched to a close fitting radiator shroud, can and usually do, move a huge increase in air flow rates over what can be expected from most electric radiator fans. this will generally reduce engine temps significantly and reduce loads on the alternator as you don,t need to run an electric radiator fan (s).
    the problem's are that as the engine rpms increases much past 3500 rpm-4000 rpm they become a huge horse power wasting drag on the engine, and the blades by design tend to change angles to reduce the parasitic losses, that fan can require well over 35 extra horsepower to spin,
    at over 4000 rpm, and thats a big problem, the flexing also eventually causes stress fractures in the blades and if used long enough over time the blades do occasionally come off and that can be a big problem as the blades fracturing instantly unbalance the fan, and shortly after the water pump bearings fail due to vibration related stress.
    there are several sources for flex fans and quality and size , and designs obviously vary so shop carefully and avoid the cheap fiberglass versions,
    READ
    http://www.haydenauto.com/Featured Products-Fan Clutches and Fan Blades/Content.aspx

    http://www.licorvette.com/Corvette Fan Clutch.htm

    http://www.popularmechanics.com/cars/how-to/a302/1772922/

    and REMEMBER CHEVY
    WATER PUMPS,
    FAN CLUTCHES
    AND
    FANS,
    ROTATIONAL DIRECTION

    VARIES BETWEEN CARS
    SO YOU MUST MATCH THE INTENDED APPLICATION FOR THE COMPONENTS BEING USED FOR ALL THREE COMPONENTS

    https://m.summitracing.com/parts/der-19118

    https://m.summitracing.com/parts/flx-1318

    https://m.summitracing.com/parts/prm-83182
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    but there is a well proven and fairly inexpensive solution
    installing a viscus fan clutch


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    if you install a viscus fan clutch at lower rpms the fan spins at almost engine rpms, the internal hydraulic friction clutch keeps the fan blades , spinning but as rpms increase and resistance to the fans blades increase, the internal clutch allows some of the engines energy to push the fan, but slippage increases, so your fan may only spin at 3700rpm-4500rpm ( this mostly depends on the fan clutch design, fan loads and clutch age and condition) the fan clutches do eventually wear out, but its been my experience they are generally good for 6-7 years before youll find any significant wear.
    use of a fan clutch can easily reduce the parasitic drag loses , by over 50% from those the engine would see without the fan clutch.



     
    Last edited by a moderator: Aug 22, 2016
  2. grumpyvette

    grumpyvette Administrator Staff Member

    Last edited by a moderator: Jun 15, 2018
  3. grumpyvette

    grumpyvette Administrator Staff Member

    "deja
    posted this"


    One other thing about the LT1 you should know early. Depending on what car your engine came from you may be too many hose fittings on the water pump. If you have an F-body engine you will need to remove and plug that bottom right hose fitting.


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    lt1 cylinder heads don,t flow coolant thru the intake to the radiator like the earlier heads do, the water pump is the exit point for coolant flow.

    [​IMG]


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    For venting off the air in the heads download this doc and follow the instructions. Its tough getting the air out, you may have to do it several times but this works.
     
  4. grumpyvette

    grumpyvette Administrator Staff Member

    If your water pumps starting to leak theres an excellent chance that the pumps seeing internal coraosion damage or the bearings are nearly gone, also so it likely needs to be replaced, keep in mind that various chevy water pump designs come in long, short 5/8" and 3/4" and forward and reverse rotation designs, and the LT1 uses a totally differant pump from the SBC or BBC so shop carefully, you won,t be the first guy to install the wrong pump, if you don,t shop carefully.
    be aware that no pump on earth will do much good if the radiator leaks , the fans not installed correctly, theres crud in the radiator fins or its passages are plugged or the t-stats not opening correctly,if your low on coolant,the fan belt slips excessively,ETC. don,t assume its a faulty water pump if the engine over heats
    check things carefully

    TRY HARD TO READ ALL THE LINKS AND SUB-LINKS THEY CONTAIN A GREAT DEAL OF RELATED INFO YOULL NEED!
    both the weiand and flowcooler brands work ok in my experiance


    http://www.summitracing.com/search/?key ... pump&dds=1

    http://www.summitracing.com/search/?key ... pump&dds=1

    http://www.superchevy.com/how-to/148-0504-cooling-system-info/

    https://www.chevydiy.com/cooling-systems-guide-big-block-chevy-engines/




    if your intake manifold is starting too corode also ID sure check BOTH the electrical grounds and the coolant/anti-freeze percentage, and ID strongly suggest adding an ANODE

    viewtopic.php?f=57&t=74&p=674&hilit=anode#p674

    http://garage.grumpysperformance.co...ing-and-the-t-stat-related-info.563/#post-717


    your intake can be repaired at any decent machine shop with some tig welding and a milling machine

    if your semi skilled with an oxy-acetolene torch you can even use this on an aluminum intake and then hand file it or dremel tool it to the correct surface



    viewtopic.php?f=60&t=376
     
    Last edited by a moderator: Jun 15, 2018
  5. grumpyvette

    grumpyvette Administrator Staff Member

    If your having problems with water pumps I,ll point out that theres a huge difference in quality between brands, and you don,t always get the best results from the name brands but the price does tend to indicate the level of quality and the pumps are usually rebuild-able if you run a 50%/50% antifreeze mix and anodes in the cooling system, and You should run Water Pump Lubricant in the Cooling System. and not just strait water where electrolysis tends to eat components and don,t excessively side load the bearings,by over tightening fan belts ,or run an out of balance fan, pumps tend to last longer, if the tensions lower
    look around for a local shop that rebuilds water pumps, they can usually do a better job than the cheap rebuilds auto parts stores sell, the bearings and seals are easily replaced and if you use quality parts, vs Chinese crap components they tend to last longer.
    an out of balance fan assembly can vibrate a water bump bearing badly enough to significantly reduce its life expectancy
    a decent hydraulic press and an understanding of how a pumps rebuilt and the replacement parts can reduce the cost of replacement

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    [​IMG]

    shop carefully theres several different bearing sizes so it might be best to visit a local water pump rebuilder,
    and get it done by their shop,
    or at least disassembly yours and measure parts before,
    ordering matched components
    [​IMG]

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    https://www.ecklerscorvette.com/corvette-water-pump-rebuild-kit-small-block-1958-1968.html
    [​IMG]

    you do realize that SBC water pumps in many cases could be rather easily and cost effectively be rebuilt,
    in many cases with better quality than original bearings and seals


    Last edited: A moment ago

    ANODES and use of antifreeze vs pure water are a MANDATORY component on aluminum water pump, radiator and cylinder head engines
    read the link
    viewtopic.php?f=57&t=74&p=4122&hilit=anode#p4122


    SOURCE:
    Zip Products, Inc.
    8067 Fast Lane
    Mechanicsville, VA 23111
    (800) 962-9632

    PARTS LIST:
    WP-116 • 56-70 Deluxe Water Pump Rebuild Kit 1 Kit
    Also available:
    WP-121 • 66-69 427 Water Pump Rebuild Kit
    WP-122 • 58-70 283/327/350 Water Pump Rebuild Kit

    ZMG-52 • Chevrolet Orange Engine Paint 1 Can
    Shop/Repair Manuals

    side loads from accessory belt drives should be balanced, if possible, if theres excess side loads on the water pump bearings, it tends to deduce expected life span on the water pump, a smaller crank pulley diam. will reduce the pump rpms , if your cooling system can work at the lower rpms that increases pump life expectancy, running a lighter weight fan assembly can help reduce pump stress levels

    edelbrock
    wieand
    FlowKooler
    milodon
    G.M. performance
    Stewart


    all have SOME good pumps


    http://www.corvettemagazine.com/engine/ ... build.html

    http://www.speedwaymotors.com/KSE-Water ... ,1824.html

    http://www.parts123.com/0000050b/242118 ... 242118.htm

    http://cgi.ebay.com/ebaymotors/Chevrole ... 0609671328
     
    Last edited by a moderator: Mar 18, 2018
  6. grumpyvette

    grumpyvette Administrator Staff Member

    LOOK THRU THIS LINK
    http://www.corvettemagazine.com/engine/ ... build.html



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    bytor posted this

    Realized I ordered the wrong water pump for use with my 78 corvette thinking any 'short' pump would work. After some research, now I know what I need. Going for a high volume pump with a 3/4 pilot and 5.8" block to hub face measurement.

    Info I found on one of the corvette forums...

    Corvette – Water Pumps
    The "Corvette short" water pump which you refer to applies only to small blocks and not big blocks. ALL 65-74 Corvette big blocks use the same, BASIC water pump casting (although 4 different castings were used). All 65-70 big blocks use a bearing/shaft assembly with a 3/4" diameter shaft, but a PILOT (the end of the shaft which centers the pulleys and fan clutch) turned down to 5/8". 1971-74 big blocks use a full 3/4" pilot.

    For Corvette small blocks, ALL 55-70 Corvettes use a "short" water pump with a 5/8" shaft. This same style water pump was also used on all 55-68 small blocks used in all other Chevrolet passenger cars with small blocks. In 1969, most Chevrolet small blocks and big blocks, EXCEPT CORVETTE, went to the "long" water pump which still used a 5/8" shaft. Block to hub face is 5-5/8 (5.625)

    In 1971, virtually ALL of the small block water pumps changed. All, EXCEPT the CORVETTE, continued to be "long leg" style but with 3/4" shaft and 5/8" pilot. Corvette continued to use a "short leg" water pump, but it was a DIFFERENT short leg water pump than used for 55-70 Corvettes. This water pump, often referred to as the "Corvette short" water pump, was set up to accommodate the large bearing and shaft assembly which used a 3/4" shaft. For 71-82 Corvette pumps, the shaft PILOT was the full 3/4". The full 3/4" pilot small block water pumps are unique to Corvettes and some medium/heavy duty trucks which also used the "Corvette short" water pump. I might also add that 71-74 Corvette big blocks ALSO used the 3/4" pilot shaft and they were the only big block water pumps which did so.

    Due to its design, the "Corvette short" water pump has a slightly greater block mounting surface-to-face of hub flange dimension. Block to hub face is 5-13/16 (5.900). Combined with the fact that the 71+ pump has the full 3/4" pilot, it is applicable to only 71+ model Corvettes (and the trucks mentioned). The "Corvette short" water pump is NOT applicable to 55-70 Corvettes unless the entire pulley system, fan clutch and fan are changed to the 71+ configuration.

    I might also add here, for clarification, by water pump SHAFT diameter, I am talking about the portion of the shaft that goes THROUGH THE BEARING. All Corvette water pumps use a 5/8" impeller shaft end. For 65-70 small block Corvettes, this means that the shaft is 5/8" all the way from end-to-end. For 71+ Corvette small blocks, the impeller end of the shaft is turned down to 5/8".

    There were several GM castings used for the 55-70 Corvette and 55-68 ALL small block "short" water pumps. However, for the 71-82 "Corvette short" water pump, there were only 2 castings ever used. 1971-early 1972 used GM #3991399. Later 1972 to 1982 used GM #330813. These are the only 2 castings which GM EVER used for the "Corvette short" water pump. The 3991399 has no drilled and tapped boss on the top for external bypass. The 330813 does have a large upper boss and 3/4" NPT fitting for external bypass. The external bypass provision was plugged with a square head pipe plug for all 72-82 Corvette applications. The fact that this boss and tapping was added to the pump was only for the truck applications that also used it.

    Chevy Water Pump Specifications Summary:
    Short-Style Pump for most 1955-72 cars & trucks (5/8" pilot shaft)

    • Fits all 1955-68 S/B Chevy passenger cars, 1969-70 350 c.i.d. Corvettes and 1955-72 light duty trucks. Has 3/4" ball/ball bearing.
    • Dimension from block surface to hub: 5-5/8". Inlet diameter: 1.80".

    Long-Style Pump for 1969-87 V8, 90° V6 & 1973-86 truck (5/8" pilot shaft)
    • Fits all 1969-87 S/B Chevy or 90° V6 passenger cars and 1973-86 light duty trucks. Does not fit Corvettes (use #8810 or #8812)
    or late-model vehicles with serpentine accessory drive belts (use #8881). Has heavy-duty 3/4" ball/roller bearing.
    • Dimension from block surface to hub: 6-15/16". Inlet diameter: 1.80".

    Short-Style Pump for 1971-82 Corvettes 3/4" pilot shaft)
    • Fits all 1971-82 S/B Corvettes. Comes with heavy-duty 3/4" ball/roller bearing.
    • Dimension from block surface to hub: 5-13/16". Inlet diameter: 1.80".

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    Last edited by a moderator: Apr 20, 2018
  7. grumpyvette

    grumpyvette Administrator Staff Member

    many electric water pumps are very well known for pumping a good deal less coolant flow than the manual engine driven water pumps after an engines rpms increase, your belt driven pump increases flow rates significantly along with engine rpm increases, the electric pump usually fails in that regard
     
  8. Grumpy

    Grumpy The Grumpy Grease Monkey mechanical engineer. Staff Member

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