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-   -   Throwing a push rod (https://www.ford-trucks.com/forums/1313442-throwing-a-push-rod.html)

jesseh39 05-06-2014 09:08 PM

Throwing a push rod
 
OKay, why in the hell do I keep throwing one push rod? the roller rocker kit I got is a 1046 from comp cams, now every time, I get my timing set, and LOAD the motor, that one pushrod throws. I thought it was the lifter, so I used the best of the old lifters according to valve wear pattern on the bottom. Now... before I tore the motor down it had two bent push rods, either over reving, or this same possibility.. the cam is new, so I don't figure with the whole hour ive had the truck running I could have killed the duration. Could it be the valve? Help.

instig8r63 05-06-2014 09:40 PM

First of all, new cam and old lifters is a no-no, but that's not why you're bending pushrods.
I'm assuming from the Comp part number, you have an FE motor. I suspect a tight or dry valve guide. Are you getting enough oiling inside the valve cover area? I would pull the spring of the suspect valve and see how freely the valve moves in the guide. Has the truck been sitting?
You can stuff a section of rope into the spark plug hole and get the piston at TDC to avoid dropping the valve into the cylinder.

bradb2230 05-06-2014 09:43 PM

are you using hardened push rods?

jesseh39 05-06-2014 09:45 PM

390fe yes, new cam, lifters, and I was under the impression that my lifter was pooched... I know its a no go, and the truck was running on that cylinder when I took it down 2 weeks ago. soaked the lifters in oil for 2 days, dropped it in. its getting good oil, but it was apart for two weeks. oil pressure is like 50psi start up, and if your valve covers aren't in, your really likely to throw oil everywhere.

jesseh39 05-06-2014 09:47 PM

no idea, what kinda push rods they are.. ones that came with the 1046 and new lifters, unless one is longer but I doubt it.. I half assed looked

bradb2230 05-06-2014 09:49 PM

could also be a sticking valve, or bad spring

JWC 3 05-06-2014 09:50 PM

Dial indicator , check your travel ....If only one push rod is bending .

bradb2230 05-06-2014 09:51 PM

if it was longer you would be able to adjust the rocker arm to set your valve lash to correct specs

jesseh39 05-06-2014 10:01 PM

Haven't bent one just yet. It just keeps dropping out. Like the cupped end isn't in the ball. Only under a load and loaded while warm.

JWC 3 05-06-2014 10:04 PM


Originally Posted by jesseh39 (Post 14325054)
Haven't bent one just yet. It just keeps dropping out. Like the cupped end isn't in the ball. Only under a load and loaded while warm.

Check the travel . Something is not proper ...

jesseh39 05-06-2014 10:06 PM

Could I have killed a love duration with having the timing out?

jesseh39 05-06-2014 10:08 PM

And how do I check the travel?

JWC 3 05-06-2014 10:10 PM

Lobe ? Timing should not kill a lobe . Incorrect break in procedure can wipe out a lobe !

jesseh39 05-06-2014 10:11 PM

I am aware. If I had the valves too tight off the start then had it running. Left it run for 20 mins and then shut it down. Could that have killed it?

jesseh39 05-06-2014 10:12 PM

But then why only one?


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