Here's the deal. I got my engine running a few weeks ago. It ran fine before I tore it down for cleaning/new gaskets. After I got it running I could here a slight bit of chatter and decided to adjust the valve lash. I over adjusted and the engine wouldn't idle right, so I had to spend an hour re-adjusting the valve lash until it would idle fine, then I left it alone. I've been busy and I havn't been able to run it for a while and it's just been sitting until today. I went to fire it up, and there is a thumping that sounds like its coming from the #8 cylinder. It idles, but roughly, and if you stand over the engine you can hear the thump on every rotation. Could it be the #8 valves out of adjustment from sitting? If so, whats the best way to adjust valve lash with the engine in the car, because I SUCK at it big time.
Are you 100% sure, because I've been told otherwise? It's not that I think your wrong, I just want to get some confirmation before I go screwing things up again.
What year are the heads? If they have the rail rockers for that year car, the studs should be threaded down to a ledge. Those are not adjustible. The only was to adjust valve lash would be different length push rods.
Is the noise a clicking noise (loose rocker) or a deeper noise? Big difference. If it is down deep in the block, you might need to pull the head and see what is up.
It's a 69 302, everything internal but the cam is stock (as far as I know, I didn't build the engine). I know that if I loosen the rocker nuts it chatters, and if I over tighten them the engine runs rough. It's not a clicking noise like a loose rocker makes, but I don't think its coming from the crank case, because I didn't pull the crank/pistons when I did the teardown, and it ran fine before then.
SERE, if all you did was change gaskets, torque the rockers down and move on. The noise could be a lot of things. Make sure your timing is set right. thumping could be a leaking exhaust possibly at the manifold donut.
Timing is good, exhaust leak is a moot point, since there is no exhaust past the headers. Admittedly this makes it a bit difficult to pinpoint the sound. Also, the engine was recently rebuilt before I got ahold of it. I think I'm going to loosen all the rocker nuts on that side and see if it idles fine, and just chatters.
Gonna try that first thing tomorrow. Thanks. Yellow, I ran through that whole procedure when I reassembled the engine, and still had loose rockers for some reason.
What cam are you running ? If it's too radical, it'll pull the rocker studs out of the heads, that's going to definately screw with the adjustment. At some point in 68 or 69 (I think), was when Ford made the switch to the positive stop rocker studs so you may have one or the other.
It's an RV cam, unfortunately I don't have the specs on it from the previous owner, however, it was running/driving for a while with no problems before I tore it down.
