By bending a pushrod how likely is it that the lifter or cam lobe were damaged? Hydraulic cam and lifter in a 428.

say you likely have no damage to the lifter or cam. Having a hydraulic lifter helped. And I've had replaced bent lifters (over-revving) on racers w/o any other misfortune. That said, it's no guarantee.

Question is: how did you bend it?

The push rod was bent by turning the engine over with a pull bar and an exhaust valve was stuck.

Had a 390 that sat for a while---the gas of today kinda breaks down quickly and gets gummy/sticky---stuck a few valves and I had 4 bent pushrods---engine ran a little rough at slow speed but not like a dead skip--pulled the covers and the bent ones were readily apparent--went ahead and replaced them all--engine runs fine now

makes it even less likely. New engine or a rusty old one?

engine that isn't good news. Could be many causes (too little valve guide clearance, valve hitting the pistons, oversize valve clipping the cylidner wall, etc.). Will you tear it down to check?

I agree with Bob, in a new engine this is NOT good news. Some kind of intereference problem is likely. Can you tell us about the combination? Heads, valve size, bore size, pistons, etc?

Jay Brown
1968 Shelby GT 500 Convertible, 492" 667 HP FE
1969 R code Mach 1, 490" supercharged FE, 9.35 @ 151.20, 2007 Drag Week Runner Up, Power Adder Big Block
2005 Ford GT, 2006 Drag Week Winner, 12.0 Daily Driver
1969 Ford Galaxie XL, 460 (Ho Hum....)
1964 Ford Galaxie 500, 510" SOHC

never started, were the lifters all pumped up ??? if not the actual valve timing is very different than the specs...the LATE closing of the int valve, due to the colapsed lifter, may allow the ex to catch the edge of the intake valve...acts the same as a stuck valve....somethings gotta give !!!

I am sure this is an elementary question for the seasoned FE gurus, but how do I pump up the lifters? And please advise me on what other precautions I should have and possibly/probably did not do.

this Crane Cams tutorial about 1/2 way down the page.

http://www.cranecams.com/?show=faq&id=3

Assuming you have non-adjustable rockers, making the two marks will tell you if the lifters are o.k. or collapsed (if collapsed, the push rod will not rise after taking the rocker shaft off).

I'm not convinced, in a new engine, that this is source of the bent pushrod. Short of taking the heads off to check for valve-piston or valve to cylinder wall clearance...

-pull all the plugs and both rocker shafts. Btw, you could mark a few pushrods before doing so (per Crane's example) and a few minutes later see if they 'rise'. Then, turn the motor over by hand (no starter!) and see if it completes 2 full turns. Reason why is to see if any nuts, bolts, etc. may have made their way into the intake manifold and down into the chambers.

-if all that looks good, I'd next yank the intake (didn't say this would be easy!) and heads and start inspecting the piston tops, chambers and cylinder wall for interference.

-then, follow the CC article on how to check for sufficient v-p clearance.

http://www.carcraft.com/howto/116_0701_valve_to_piston_clearance/index.html

If you elect not to go this far, do not attempt to start the engine or use the starter to spin it over! More damage could be done until the source of the problem is identified!

If you'd like to get a rough idea of what P-V clearance you have before pulling the heads off, just get a valve spring pressure tester.

Get the piston to about 10* BTDC on the exhaust stroke and use the tester to open the valves and see that you can compress the spring at least about .1 inch or so and do this ever few degrees of the crank until about 10* ATDC. As long as you could compress the spring at least this much you should be OK.

I think the exhaust valves tend to be closer to the cylinder walls so you should also be able to tell if the valve hits the cylinder wall before full open as long as you don't have monster springs. Just get the piston down into the hole first so you can compress the spring without the valve hitting the piston.