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View Full Version : Contantly bending push rods????


Wet Dream
09-01-2002, 04:10 PM
Engine is a Ford 460, well built, but for some reason, it has bent 2 pushrods within the last week, same cylinder. With the new pushrod installed, it would idle perfectly, but as soon as you stab the throttle it blows the rod. This is the same cam and lifters that have run perfectly this whole season. Anybody have any input on this?? I have heard of lifters collapsing, but never becoming solid. Could this be the culprit? Please let me know what you think.
hoolign
09-01-2002, 04:58 PM
[ September 01, 2002, 05:58 PM: Message edited by: hoolign ]
wsuwrhr
09-01-2002, 06:19 PM
You have some kind of bind. I don't know what kind of valve clearance you are running, but you may want to recheck that cylinder. Make sure the spring isn't broken either. What have you checked already?
Brian
Wet Dream
09-01-2002, 06:51 PM
This is on a friends engine, but I was curious about the valve clearance also. There aren't any broken springs and oil pressure is 60+ psi. Could the valve be opening up (or not closing all the way) when the piston is on the up stroke? The cam is the same that has been in it all summer long.
Infomaniac
09-01-2002, 08:26 PM
Valve spring coil bind or retainers smacking the top of the valve guides. Valves guide to valve stem clearance problems (sticking valve)
[ September 01, 2002, 09:28 PM: Message edited by: Infomaniac ]
Infomaniac
09-01-2002, 08:27 PM
I hate it when I do that
[ September 01, 2002, 09:30 PM: Message edited by: Infomaniac ]
Tinkerer
09-01-2002, 08:37 PM
I would think valve sticking. What valve is it on?? If it is the intake valve pushrod that is bending check the exhaust valve train to make sure that it is opening properly. The intake valve wont want to open if the exhaust valve didn't do it's job properly.
spectras only
09-01-2002, 10:16 PM
[QUOTE]Originally posted by Wet Dream:I have heard of lifters collapsing, but never becoming solid..Yes ,lifters can become solid ,hence the introduction of anti pumpup lifters like Rhoads for instance!I used Rhoads for decades in 460's 429's and never had a problem with pushrods bending.You have to setup these anti pumpup lifters with Zero clearance ,because they act like solid lifters.No 3/4 turn preloads like conventional lifters! You might have some coil bind too like someone mentioned above.Check all your springs at maximum lift to have at least 050 thou between coils for safety margin.