Originally Posted by rusthater89
I was talking to an old school friend who had a 350 chevy crate engine dropped into his ride recently.
The Story goes like this.
He had the car towed to a local Midas after the guy dropped the engine in to weld on a exhaust. He hadn't even heard the engine run yet. He came to pick the car up when the exhaust was done. the Midas shop tells him the engine isn't running right. I agreed as well when I took a ride with him later. It was idling rough and was lacking power like maybe a valve train issue. My buddy called the guy who dropped the engine in who told him to not sweat it and that he woud make any minor adjustment when he came in for the 1000 mile warranty oil change.
to sum it up when my buddy bought the car back the guy tells my buddy he blew the valve train by over revving. He shows my buddy these bent pushrods and tells him the rockers were wrecked. The push rods were S shaped. My buddy told him, "No way man I babied that thing." I can confirm that as well. the Mechanic then tells my buddy the guy from midas must have raced the car and over revved it causing it to blow.
when he confronted Midas about it the Midas guy just told my buddy to sue the installer of his crate engine.
This story confuses me and my buddy is screwed. I think the guy didn't time the cam right. I may be wrong. Maybe it was over revved and the valves floated.
can anybody give me their opinion
If the gas has gone bad, this will gum the valve stems up (especially the intakes, but both can be affected) to the point they will stick like you wouldn't believe. The result is bent p-rods.
ANY and EVERY time aftermarket valve train parts- especially higher ratio rocker arms and higher lift camshafts- are installed in an engine, the clearances of all the critical areas have to be checked and verified to be correct, along w/selecting the correct push rod length to have the correct valve train geometry, as well as the correct springs to match the camshaft.
is a list of valve train points to check.
I doubt all the pushrods are bent. On a cylinder that still has unbent pushrods, I would start by checking for:
• coil bind at max lift
• clearance between the guide boss and the retainer at max lift
• spring installed height
• broken valve springs
• valve to piston clearance- if the cam were out of phase, the valves could be able to hit the piston. Which valve (intake or exhaust) would depend on whether the cam was advanced (intake valve) or retarded (exhaust valve). Check to see if all intake or all exhaust pushrods are bent, or if they're random.
There are other reasons the pushrods might get bent, like a stuck valve/tight guides, valves incorrectly adjusted, over revving, hydraulic lifter pump-up.