|
|
Post by jayd on Apr 11, 2006 8:54:20 GMT -5
Ok so I have a '73 buick 455 engine in an '80 pontiac. Anyhow, I had too small of a radiator in the car and overheated it to the point it died and wouldn't start for a while/properly. So I took apart the engine and looked at everything and nothing was out of order. Put the engine back together and in the car. Now, the car runs great, the only problem is, if I run the car for a long period of time or if I race I always bend the same rod! Any idea whats wrong?
|
|
|
|
Post by DanD on Apr 11, 2006 12:13:25 GMT -5
I’m going to assume you’re talking about a push rod and not a connecting rod.
It’s been a long time since I’ve had a big block Buick apart but didn’t they use a common rocker shaft (one per head) for all of the rockers to pivot on?
If so I’d be looking at the shaft where that rocker pivots on the cylinder that keeps bending the push rod.
The overheating may have caused the shaft to wrap or become scored; causing that rocker to stick and bend the rod.
It also could be a valve guide that has been scored and after the engine is up to temperature or at high RPM; is grabbing hold of the valve stem holding the valve still and bending the rod.
One other possibility is that the overheating has stretched a few things like the valve stem or the connecting rod. Again when the engine gets warm or when you rev the crap out of the engine, the piston is kissing the valve stopping it and in turn bends the push rod.
Something has to be stopping in the valve train to bend the push rod.
Now if you’re talking connecting rod; pull the engine and have the crankshaft and the engine block line-bore checked.
Dan.
|
|
|
|
Post by jayd on Apr 11, 2006 13:26:25 GMT -5
Yes I am talking about a push rod. Do you think getting the heads redone could fix the problem?
|
|
|
|
Post by re-tired on Apr 11, 2006 14:35:32 GMT -5
I agree with Dan ,the only other thing is a defective lifter . My money is with dan. Yes a valve job should fix if that is problem. Be sure to tell the machinist about your problem.
|
|
|
|
Post by jayd on Apr 11, 2006 19:06:31 GMT -5
thx guys
|
|
|
|
Post by idol on Apr 15, 2006 7:13:29 GMT -5
Hi Guys,
I'm more inclined to believe that a lifter has failed. Whenever the engine tends to overheat or run hot for long periods, lifters tend to gumup and solidify.
If this problem came to me my first area of focus would be on the lifters, before I'd consider the valve or other train parts.
That is not to say that other parts couldn't be bad also, but I'm leaning toward a bad lifer as the most likely culprit. Idol
|
|
