Bent pushrods without hurting valves

[MSDGN]

Is it possible to have bent pushrods without hurting the valves?...I had a problem with my trans on a 1/4 run some time ago and hit the rev limiter when I shifted to 3rd gear...RPM's shot up to 6800...actually past the rev limit I have set at 6500...next day decided to do compression test and everything was fine...I decided to check the pushrods anyways and found a couple of them bent...not real bad but you could see the bend just by looking at them...I'm assuming the only they can bend is if they smack the pistons...or can it happen another way?...I don't think any of the valves are bent because the compression test would have shown that plus I've run the car many times after that...latest run was 10.50 @ 128+...I don't think the car would still be running that fast if valves were bent...or am I thinking wrong here?...the car has a billet roller...T&D rockers..GN1's...I've had it up to 6300 RPM's many times with no problems...also have done leakdown and it's fine...around 5.5% in all cyls...again I would think a bent valve would be easy to see with a leakdown...

 

[Nick Micale]

Is it possible to have bent pushrods without hurting the valves?...........

Yes. There can be various reasons to bend pushrods, one of which they are just not strong enough.

In our 9 & 10 sec. engines a GOOD set of pushrods costs over $100.

There could be valve train mis-alignment, guides sticking or other problem.

 

[xsbc63x]

when i pulled my engine apart, i had 3 bent push rods, not sure why as i just bought the car, but the valves looked fine.

 

[pacecarta]

.I'm assuming the only they can bend is if they smack the pistons...or can it happen another way?...

if the cylinder is under pressure the valve wont move and the rod will bend , doesnt have to hit a piston

 

[MSDGN]

OK...that makes me feel better...I did go ahead and replace all the pushrods with some heavy duty ones from Comp..

 

["Turbo-T"]

To echo what Nick said...if they're not strong enough you'll bend them...I bent one on a high compression V8 I built once just spinning the engine up to 5k. Later found I should have used chromeolys and not steel. Once I swapped them out to chromeolys I never had anymore issues.