My question is: Could timing set too far advanced cause a bent push rod? Thanks.
jor

 

There is no real corrolation between dist. timing and pushrods. Now, if you had CAM timing too far off, a valve might tap a piston and bend a pushrod.

 

Freightrain, I didn't expect an answer in the middle of the day. Thanks. I read your response and I want to make certain I understand. If a plug fires too early there is no way it could result in a bent pushrod but if the cam timing was a bit off that could indeed cause a bent pushrod.

Here's what happened. I had my 390 rebuilt with a pretty big cam (Crower, 222 and 228 at .538 and .552) with the matching springs. I fired it up at TDC, advanced it until it was running better, ran it for 15 minutes between 2,000 and 2,500 revs and shut it down. I drove it around the block a few times and up to the exhaust shop. On the way back from the exhaust shop, a terrible banging or tapping (metal on metal) started. Then it stopped. It then seemed to run perfectly. On the way home form the parts store, it started again. I took off the right valve cover this morning and number 4 intake was bent bad.

What is you best guess on this? Thanks.
jor

let's say timing was as far as 25 or 30 BTDC

 

Dist. timing (when the plug is fired) can't bend push rods. I would susupect that with the amount of lift you are running that either the valve spring are binding at full lift or the valve is hitting the piston. Pretty much the only two things that will cause your problem. Well, there is always the valve springs are so strong that the push rod can't push that hard and bends. In any case it is a valve train problem.

 

Thanks, Bear. I took a week off of work and thought I had done a good job on this engine swap. Everything all clean and painted, new clutch and pressure plate, new peripherals. Anyhow, my machinist assured me that he had this thing set up right (they build lots of race engines). It is what it is; I just wanted to be certain that I didn't do anything to cause it. Thanks for your answer. I guess this one's on him.
jor

 

I wonder if actual piston/valve clearance was checked?? Spring bind is a possibility, floating is another.

That cam sounds about just like the one I have in my 390. I have stock(real stock, original Ford) pistons and have no piston/valve clearance issues.

For whatever reason...#4 got hung up on something.
I wonder if it ate something?? Check the bottom of the carb for missing screws? anything? Since it was the intake valve that leads me to believe something might have come through it.

My race car ate a carb screw once..it left actual thread imprints in the top of piston and head! It was a Holley, and it was the bottom screws that hold base to throttle plate.

 

Thanks for the advice, Freightrain. It's a brand new Edelbrock 750. I looked at it last night and didn't see anything amiss. The pistons are Speedpro L-2291-F. There is no possibility that I dropped something in there myself as I was super careful. I have it back now at the machinist's and I am waiting for him to call. I am hoping I don't get jerked around on this as it sounds as though it was not set up right (assuming your ate-something idea didn't happen).
jor

 

Had my 428 build at a shop in Bend, OR. and they used NAPA lifters on my engine and another 428, both went into 64 Galaxies and both had problems with bent push rods. I pulled the intake off mine and pulled out a lifter to check it, it would not compress. So I put in a in A new set from differant parts house and I had no more problems. I bent a total of 8 push rods before changing them. The other guys engine did the samething and he changed his and had no more problems.

 

Well, I hope mine is that simple, bertha66. That would be great! I'm not sure what make he used for lifters. Thanks and I'll post as I learn more.
jor

 

Ya, if the hydraulic valve sticks...then it will not compress and thus holding the valve in the OPEN position !! Not good!!

I've always run solids so never had to deal with issues like this. But, with the all the tiawanese junk running around today I would not be surprised.

 

Hey Larry, would you sell me some Hydraulic Valve's ?? Will they match the Hydraulic Lifter's I allready have ??

Thanks,

Russ,

 

Oh...everyone's a commode-i-an..............LOL!!

The valve INSIDE the lifter.........for those that don't actually realize what I was actually talking about! The little ball that rattles when a hyd. lifter has never had oil in it.

 

Yeah Larry I knew what you were trying to say!!! LOL....

No actually I thought you developed a Hydraulic Valve incase your lifters pumped up??

Therefore the Valve still wouldnt slap the piston!! LOL....

Yes you are refering to the Check Ball Sir!!

Russ

 

I have no need........since I run solids! None of that quiet, non-adjusting crap for me..LOL!!

Don't think there is enough room to build all that into a lifter. Even though Rhoads did make the bleed down type. Basically a "leaky" lifter! I never saw the need for that either? Why would you go thru the trouble of using them?? Guess I never had the need to make a cam seem "smaller"

 

just wondering.

to run solids do you really have to plug the top oil galleries (or what ever it was you were supposed to do)


What would be the effect of not doing that? (just wondering)