Thread: Rebuilt 350 won't fire-up!

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I just rebuilt my 350 and now it wont start. It has gas and spark, and I have been trying for a week but nothing i do works. I think it's timing but I think I have tried every way there is. Cam and crank are dot to dot on the timing chain also.

Make sure you have your rockers adjusted right. I went to a fella's house who had the same problem you did. I ended up pulling #1 plug to insure he had the distributor set right. I told him to crank the motor over while I held my finger over the plug hole. The motor turned over a few times and now compression. Come to find out he had the rockers too tight. Once he got that straight the engine started right up.
You must have an igntion timing/firing order issue or rocker issue if your getting gas to the motor and you say you have spark.

I wholeheartedly agree with 73RS, check the rocker height/valve lash. I had a very similar situation when I put in a new 350 into my Camaro. I must have timed it every way possible. It turned out that I had several of the valves too tight.

I had always read that for hydraulic lifters you should tighten them up until there is no play in the pushrod. I took it way too literally and tightened them until I couldn't even turn the pushrod, then I even tightened it another 3/4 turn. Finally, after failing to get the engine to fire properly, I backed them all off and tightened them untill there was no "vertical" play. The engine fired up right on the first crank.

Originally Posted by camaromotorhead

I just rebuilt my 350 and now it wont start. It has gas and spark, and I have been trying for a week but nothing i do works. I think it's timing but I think I have tried every way there is. Cam and crank are dot to dot on the timing chain also.

I hope you haven't damaged the cam lobes/lifter faces by grinding on the starter for so long with no oil splash going to the cam. What valve springs are in the heads right now?

A TIP
When I rebuild or just change cams I always set the lifter with the intake off. I rotate the engine by hand till I get a cyl. TDC then adjust the rockers to mid stroke on the lifter. You can see this by just looking at the lifter where the pushrod mates to it. You do this before pumping up the lifters. Just do each cyl. 1 at a time. I hate to go back and adjust them oil every where. This can be done with pumped up lifters but you have to be carful not to bend the pushrods.

It has stock springs and an RV cam. I'll try the vertical play method today. I havent cranked on it to much because of that reason, I'll let yall know how it goes.

Thanks

Originally Posted by DennyW

I never did like the twist the push rod thing. Vertical play is the way to set them.

how does that work?

keep in mind with the timing gears dot to dot, that is #6 in the dist, cap, not #1. also to be on #1 in the cap you need to be on the comp. stroke.

what if you have roller rockers

thanks man

Originally Posted by DennyW

Same thing. The 0 clearance still has to be obtained. The rollor just gives you less friction.

with roller rockers, there needs to be valve lash,,,depending on the cam, start @ about .010 and go from there, unless specified by the maker. it'll be a good place to start till the engine runs, then they need to be re-adjusted after motor warm up

Doesn't the lash depend more on what type of lifters. From what I understand, the cam is ground differently for solid, hyd. or roller lifters.

You can have roller rockers and hyd. lifters.

ur right denny, i never thought of it having hydraulic lifters... of course my experience with roller rockers never included hydraulic lifters either... my mistake... ok,,, hows this, 0 lash hydraulic lifters, roller lifters, depending on how much cam, then start out @ .010 lash and and least get it running, or at least hopefully.

Originally Posted by 73RS

Make sure you have your rockers adjusted right. I went to a fella's house who had the same problem you did. I ended up pulling #1 plug to insure he had the distributor set right. I told him to crank the motor over while I held my finger over the plug hole. The motor turned over a few times and now compression. Come to find out he had the rockers too tight. Once he got that straight the engine started right up.
You must have an igntion timing/firing order issue or rocker issue if your getting gas to the motor and you say you have spark.

,,,I HAD THE SAME PROBLEM,,,I HAD 2 CRACKED HEADS,,,, THIS WAS THE PROBLEM FOR ME,,I DID A COMPRESSION CHECK AND ALSO I SEEN WATER COMING OUT MY SPARK PLUG HOLE..(MAN I HATED THAT,,THE GUY I BOUGHT THE ENGINE FROM ,,,LIED TO ME,,CAUSING ME A NIGHT MARE ,,,,good-luckALSO LIKE THE OTHER MEMBER SAID MAKE SURE ALL YOUR VALVES ARE ADJUSTED PROPER,,, YOU NEED TO DO A CHECK ON ALL YOUR TIMING NEEDS ..GO THROUGH THE GENERAL STEPS TO MAKE SURE YOU HAVE DONE EACH STEP CORRECTLY!!

Can someone explain just a bit more on that o clearance as I seem to have same problem freshly built engine noisy roller rockers. When you wind down and get 0 play on the roller wont it adjust itself by pumping up lifter different next time around, I adjusted all of mine "pedestal mounted" locked them up with internal grub screw ran the engine, and it was tappety so ripped the covers off and all rockers that werent in there cam movement had lots of play. If I adjust them again will this not keep happening. I know im missing something but just cant work it out