Starting Issue after fresh rebuild

W

wildjyoung

Member
Okay, I started my new engine for the first time yesterday. It fired up and ran like a champ for about 5 minutes. Oil pressure was a stable 50-60 PSI. It was a little bit rough but just needed a timing adjustment. I started adjusting timing and the car died. I started turning the key and the engine started backfiring very loudly. Obviously, timing was horrible out. Finally, the battery died so I quit for the night.

I went back today and charged the battery and tried to start it again. The engine would barely turn over with a fresh battery. I went ahead and put on a new starter because I used an old one and jsut figured it was dying due to age and high compression. With a new battery and new starter the engine would still only turn over slowly and almost seemed like something was holding it up.

I am lost and have no idea. Why would it run so well on the first start up and then turn over so very slowly today? Is it possible the auto tranny could be somehow holding back the engine. Perhaps the fluid cooling lines are reversed and pressure cannot escape?

Any help or suggestions would be amazingly appreciated!
 
three quick questions?

HAVE you verified TDC on the damper and timing tab and are you using a timing light to set timing?

did you gap the ring end gaps at at least .004 thousands per inch of bore diam. (about .016 MINIMUM on most SBC)

have you pulled all the spark plugs and see if it spins easily with no compression?

don,t panic its most likely minor, but start from the basics, checking thru each potential problem
 
Thank you for your quick reply. I am freaking out a little as this was my first engine build. Although, I did have someone experienced helping me.

1. Yes, I have verified TDC on the damper and timing tab. The first day it ran fine and when I went to adjust timing light is started having issues.

2. Yes, the rings were gapped by an experienced engine builder (subjective I'm sure) during assembly

3. No, I have not yet pulled the plugs to see if it spins without compression.

I checked the oil and it is completely clean, no metal particulate or sheen.

Thanks so much for your help!
 
Im reasonably sure its fairly minor if you had someone experienced check clearances and index the cam, etc.
let us know what you find with the spark plugs removed and if theres any indication of coolant in the cylinders or if you find other symptoms.
have you re-adjusted the valves yet?
many guys adjust them cold and get them too tight, at idle with the valve cover removed temporarily,simply backing off each rocker nut untill the rocker clicks and slowly tighten untill it just stops than add an additional 1/4 turn
 
The guy who assisted me used to work in a machine shop building motors and builds them for racing regularly. although, he did everything so quickly it seemed rather careless. We did not have to file the rings or anything because he said they were good. Who knows.........

I called him and he thought my timing was horribly off.

I will pull the plugs tonight and let you know what I find.

Thanks again for your help! You are such a great resource for us newbies!
 
Well, here is what I did and my findings.

I took out all spark plugs and still struggled to get the engine to turn over. The spark plugs all looked good but were covered in fuel and small amounts of black soot.

I pulled off the valve covers and it appeared that very few valves were open. I proceeded to loosen all rocker arms until I could wiggle the pushrods. Some of the pushrods were very tight. Much more so than when I first adjusted them. This was my first time, so perhaps I adjusted them incorrectly. I pulled out sporadic pushrods and they were in new condition with no bends.

After loosening the rocker arms I was able to turn over the motor with a breaker bar and socket on the balancer. I spun the motor over by hand and had a couple ounces of fuel pour out of the spark plug holes of cylinders 1, 2, 5, 7, and 8. Maybe the others as well but I did not notice. The motor was not a breeze to turn over but was smooth and I only felt the resistance of the rotating assembly, balancer, etc. No weird sounds or anything like that.

As for background on the engine. It is a 350 bored .04 over with Eagle crank, rods, clevite bearings, speed pro pistons/rings. Block is zero decked and is set up for a roller cam. When short block was complete it took around 25-35 PSI to spin the motor over and was extremely smooth. It has the Lingenfelter 74216 cam and high flow TPI intake. I put on AFR 180 heads. Estimated static compression is 10.25:1 and dynamic is 8.1:1 I used 30 lb bosch injectors and had a custom chip burned by PCM's4Less. I have a built 700R4 and 2,600 B&M holeshot converter.

Thoughts, opinions, and next steps would be MUCH appreciated! I am just hoping I did not screw something up too badly. Been working on project with my dad and brothers for 4 years and would hate to have to back track. Plus, I want to drive the car!

Thanks again for everything!
 
that much fuel in the cylinders strongly suggest the fuel pressure is far too high or the carbs way out of adjustment or the needle seat valve is defective, step one will be to check to make sure that the oil is not diluted with fuel, if it is drain and replace as you don,t want to blow the oil pan off if that fuel ignites.
step two verify the fuel pressure it should be a steady 5 psi or very close to it, if not you need a RETURN LINE STYLE FUEL PRESSURE REGULATOR

READ THESE

viewtopic.php?f=55&t=211

viewtopic.php?f=55&t=1939

ADJUSTING THE VALVES CORRECTLY is best done at idle
READ THIS

viewtopic.php?f=52&t=196

once the oils verified fuel free and you adjust the rockers correctly you can locate the source of the fuel, a good bet is a defective carb or badly adjusted carb, so if you have a second carb try that for now and let us know the results
 
I am running TPI fuel injection but think my pressure was way too high. I tested and the fuel pressure was 50 PSI with stock being 42 PSI. Additionally, I installed 30 lbs injectors.

I am going to adjust back to 42 PSI (stock). Should I go lower?
Change oil and use 1 container of E.O.S, 1 container of marvel mystery oil, and the rest 10W30 dino oil
Secondly, I looked at the valve lashing guide you provided and am going to correctly lash valves
Lastly, I am going to set static timing at stock 6 degrees BTDC and try to start then use timing light to get into time.

Some have recommended that I should put oil in the cylinders before starting because the gas has washed out all lubrication and caused ring binding. Is that even feasible?

Lastly, could any damage have been caused by running the engine extremely rich for 2-3 minutes with another 4-5 minutes of cranking?

Thanks!
 
squirting a bit of MARVEL MYSTERY OIL into the spark plug holes (about a teaspoon in each), to lubricate the upper cylinder's before you spin the engine a bit to spread the lubricant over the cylinders and rings and only THEN replace with NEW spark plugs would be my suggestion, ID drop the fuel pressure to 39-40 psi but the injectors must be leaking or the spark plugs not firing to get that much fuel remaining in a cylinder, the chances of several injectors leaking at the same time is low so ID suspect, theres an ignition issue, the most likely ignition,issue is timing thats off enough so its not lighting off the cylinders
 
Thank you sir!

So far I have done the following:

adjusted the valves, the right way (used your links).
I lubricated the upper cylinders with Marvel Mystery Oil
Drained the oil. The oil was heavily diluted with gas. I estimate I had about 2-3 quarts of gas in the oil
Reduced fuel pressure to 39 PSI
I ran the pump for 5 minutes tonight and left the oil pan empty to see if I got bleed through the cylinders, which I guess would show a leaky injector?
Put the engine on 6 degrees BTDC

Friday I am going to check the oil pan for gas. In none, I will fill with EOS, 10W30, and Marvel Mystery Oil
Prime oil system
Install distributor
Try to start the engine again!

Is there anything that I am missing?

Thanks again for your help! I cannot express how much you have helped me with this project/learning experience!

Have a Great Thanksgiving!!!
 
Well, today I put everything back filled her with the oil mixture and SHE FIRED!

She ran relatively smooth, oil pressure was at 50 PSI, and it sounded good! However, I had to keep the throttle open about 50% to keep it running. The headers started glowing bright red, so I shut it off and started messing with the timing. I was not able to get her running again. She would start to run for about 2 seconds and then quit.

No fuel was detected in the oil, so I am assuming the fuel pressure is better. However, the oil does smell minty from the Marvel Mystery Oil.

Why would I have to keep the throttle open to keep it running?
Is it normal for headers to glow red?
Lastly, why does Marvel Mystery Oil smell minty? LOL

Thanks so much and I am looking forward to your reply so that I can start again tomorrow!
 
it sounds like you've either got several defective injectors, or the ignition timings not correct, start by verifying the TDC marks are CORRECT, and that the ignition timings at 6 BTDC at idle
then once that's done if its not running correctly,you'll need to drop back to the basics and verify each step.
VERIFY THE IAC and TPS ARE SET CORRECTLY AND THERE'S NO VACUUM LEAKS

HEADERS RUN HOT , in most cases due to retarded ignition timing or a LEAN fuel/air mix, your timing tab or damper may not be at true tdc, and it sure sounds like the fuel/air ratio is way off,check for loose gaskets or hoses. can you pull trouble codes?
 
Thanks Grumpy, I will go back over the basics today and post results.

The car is not throwing any trouble codes. I put the computer into diagnostics mode to fully extend the IAC, then I disconnected the sensor per instructions I received. Was this correct? The TPS is old but I am going to verify this morning that it is at .54 volts at idle.

Thanks again and I will let you know how it goes.

Josh
 
I tested the TPS and it was only reading .1 - .2 volts at idle and would only go to 1.2 at WOT. So, I replaced it and the car fires right up and does much better. However, it revs right up to 2,100 RPM and stays there. Although I did not let it run for very long because the headers turned red again. I tested the new TPS and it is right within spec.

A mechanic friend of mind stopped by and said my distributor is likely off by a tooth causing the timing to be retarded even though it is set a 6 BTDC. He instructed me to pull the distributor and drop it back in so that it moves back one tooth.

It sounded much better and had throttle response, which was much better than before.

Does the distributor being off by a tooth make sense?
 
Well today went much better; however not without issues. The timing is set correctly and is advancing with engine RPM's. I start the car, it fires right away and immediately goes to 1,500 - 2,000 RPM. It stays there for about 15 - 20 seconds and starts to decline briefly before it revs up to 3,000 RPM and steadily increases. At no time were the headers turning red. The engine now sounds good with no pre-detonation or back-firing.

I verified the IAC is closed and that voltage readings on the TPS are correct. The computer is not throwing any codes.

Does the surge to 3,000 RPM mean a vacuum leak? All vacuum lines are new; however I am thinking I could have a vacuum leak in the intake runner gaskets.

As usual, your help is greatly appreciated!
 
wildjyoung said:
Well today went much better; however not without issues. The timing is set correctly and is advancing with engine RPM's. I start the car, it fires right away and immediately goes to 1,500 - 2,000 RPM. It stays there for about 15 - 20 seconds and starts to decline briefly before it revs up to 3,000 RPM and steadily increases. At no time were the headers turning red. The engine now sounds good with no pre-detonation or back-firing.

I verified the IAC is closed and that voltage readings on the TPS are correct. The computer is not throwing any codes.

Does the surge to 3,000 RPM mean a vacuum leak? All vacuum lines are new; however I am thinking I could have a vacuum leak in the intake runner gaskets.

As usual, your help is greatly appreciated!
Click to expand...


if the TB adjustments correct and the blades not held open by the screw adjustment,on the drivers side, then your probably correct its a vacuum leak, start by closely examining the plenum and runners for leaks
 
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