You replaced the cam and lifters. Were the timing gear marks aligned properly? Is it the correct firing order for the new camshaft? What type of rocker arms and studs are on the car? If it is the old positive stop rail rockers, fine, just tighten and go. If it is studs with adjustable rocker arms, how did you preset the rocker arms? Align the timing pointer to 10 before TDC, or TDC. Pull the cap and make sure the rotor is pointing to #1, and both rockers on the #1 cylinder should be up with little to no spring compression. If it is a points ignition, is the gap within spec? Are the plug gaps correct for they type of ignition system you are using? Have you documented the compression on all 8 cylinders? If so, how close are they to each other? Is the carb filling with fuel? When the throttle lever is actuated, does any fuel spray from the jets into the primaries?
I did all that already and went back over it a couple times... the compression is very low but that shouldn't prevent an explosion when spark, fuel, and air mix... I should still get a bump or two even if it stalls out after 2 seconds right?
When installing I matched them with the old ones and they were the same size. I also cycled the engine by hand to see that all rockers moved smoothly and valves closed completely. I understand that the engine won't stay running if I had these problems you've all mentioned but I can't even get it to turn over for 1 second. Nothing, not even a fast turn and backfire.. you take the carb off and spray starter fluid down the intake it should at least backfire right? I got nothing...
I dunno if it applies to automobile engines but I've run lawn mower engines at 25psi(leaking valve). At the least, it proves when spark happens there was a explosion. Meaning there should be at least a poof or pop now and then. If cylinders are "washed" with gas, squirting a half ounce of motor oil in cylinders will bring compression up. If it doesn't increase, problem is a valve/timing issue. If plugs are not new, usually they won't fire when wet with gas.
60 should be enough for ignition. I assume this was a running engine immediately prior to the cleanup? When you replaced the points, was the condenser also replaced?
Have you gotten this engine running? How did you determine the valves were closing completely by cycling the engine? More detail please.
Yes points and condenser but I didn't buy it running so I can only assume based off the sellers info which was about a year ago now..
It was on a stand before install so I inspected all valves through exhaust ports and also before installing the heads. That was part of the top end rebuild to clean and seat each valve.
Are you absolutely positively sure you do not have the valve lash set too tight, therefore the valves are not allowed to entirely close or close late? That would lead to low compression and prevent the engine from firing. I use the following procedure for hydraulic lifters:
I've also attached a PDF file with the same instructions. The picture in my previous post may be difficult to read.
A stock 302/351 to '77 or so does not have a valve lash adjustment, these use positive stop rocker studs. Of course it may be possible to replace the jamb nuts with adj type and use locks. What I can't remember is if the thread pitch is same. With positive stop studs, adj nuts would allow opening lash but not reducing it.
Crazy Comet you are correct on a stock 302. But now after having looked back over this thread which began in 2016 and then jumped to very recent posts, I'm not sure we are discussing an in line 6 or a V8 engine not starting.
