Why would someone put two different length push rods in? In one cylinder I have a intake and a exhaust push rod that are .15 longer then the rest. I have a ticking or a claking sound could that be the problem?

 

There shouldn't be 2 different size pushrods.

 

Maybe that one is bent.

 

I think if they were bent the length from tip to tip would measure shorter in a straight line.
My thought is that someone has been into the engine and screwed up.

 

None of the push rods are bent, rolled them to see there not bent or damaged in any way. 14 out of the 16 push rods are 7.800 in length, and 2 out of 16 push rods are 7.950 in length. I noticed when I was looking for the tick or clak it was coming from the side and around the same place as the 7.950 length push rods, could that be a cause of the tick or clak? Possibly the valve is opening to much due to the length and is smacking the piston?

 

more like the rod is depressing the lifter to it's absolute bottom, or nearing it's absolute bottom, and it's pressing all of the oil out- and you're hearing an empty lifter rebounding- or trying to rebound... as far as being too long, it sounds like the lifter is taking the blunt of the blow instead of your valve/valve springs.. I'd consider myself lucky and swap them out for new lifters and matching rods..

 

Correct Magnum pushrod length is 6.925" not sure what engine you are working on.

 

Thanks for the info Drew, I have already ordered new lifters and push rods. Got stock length Elgin push rods hardened. I have Elgin lifters too. The old lifters looked brand new too which was weird. I hope it was the lifters vs my cam or valves. Im glad i took it apart too find this out, im glad to see that this motor was very clean minus the guy went a little crazy with the rtv!

 

Sorry im working on a Chevy motor. I didnt see anything like this on the forum, the po rebuilt the motor and I hope nobody runs into the same problem.

 

Those are too massively different lengths in pushrods, i'd pull the heads and check for piston damage.

If 7.950 is the correct length, you got lucky that the shorter ones didn't fall out. If 7.950 is right, I can't imagine they wouldn't have been bent to he'll and back, unless the valve room the damaging blow. Better consult a chevy expert for your year of engine to determine what the appropriate length should be, and if a cam has changed the length needed.

Usually even an aggressive cam will require a length of only about .025" longer. They shave the base circle down to increase the lobe's perceived lift, and the longer pushrod is necessary to make proper lifter preload on a lifter that sets just a bit further down in the block at zero lift.

Remember that any lift at the cam gets multiplied by the rocker arm ratio, so even small amounts of added lift at the cam gets multiplied by 1.5-1.7 times.