Pushrod question???

[Squidog]

Heard a clicking noise that became progressively louder on the passenger bank of my 302. Pulled the valve cover and checked all the rockers and pushrods. Found two in their respective positions to be looser than the other and pulled them. This is what I found.
109639

Balls had seperated from the end mating with the rocker on one and another end that mated to the lifters. Fortunately I was able to retrieve the ball. MY QUESTION: Has any one seen this before and does anyone know the cause? Stock length 6.272 push rods from Mustang Unlimited. Look to be a defective batch? One appeared to operate in this condition long as its end is mushroomed a little. They are stock length so I don't think they are too long, and all set up with rotation and proper preload at assembly...Baffled, but going to change all Pushrods

Looking to replace. Have GT40 Heads, Trickflow Stage 2 cam, Crane 1.7 rockers

[scottiec]

whoaaaa this is wild. Never seen it. Question, what valve springs do you have? what is the installed height? Something tells me your cam plus the 1.7 rockers is too much lift and putting pressure on your pushrods...

[Squidog]

I Lied I have a trickflow stage 1 cam (similar to E303??) not a stage 2. Secondly, heads were used SVO heads that came with springs from a working 302 engine. This engine was a solid lifter arrangemetn but I am utilising Hydraulic liftres. I'm thinking insufficient weld?

[frankb]

Squid: I agree with Scottiec. Did you check for proper pushrod length (rocker tip contact pattern)? Valve to piston clearance? If all these are OK, you may wish to replace the pushrods with one-piece hardened ones. A bit more $$, but worth it!

FrankB

[NAZ]

Defective parts? Perhaps. But you have a variety of non standard parts all playing together and you should check that they are all playing nice with each other before throwing more parts in the mix. Frank has the right idea. Anytime you start mixing parts you have to check clearances even if the parts are allegedly compatible. If not, you could be disappointed in the results. And if everything check out Frank is right about the one-piece pushrods. I just custom ordered some today for less than $150 for a set of heavy wall hardened chrommoly.

[Big Blocker]

Quote: "This engine was a solid lifter arrangement but I am utilising Hydraulic lifters."

Solid lifter cams use / need a lot more spring pressure then today's hydraulic [roller]cams. Sounds to me as though you have too much spring pressure working on your valve train - not uncommon for pushrods to fail with excessive force working against them - they are the weakest link in the chain from valve tip to base of lifter.

I'd pull one each (intake and exhaust) and have the spring pressures verified - might be to your advantage to swap out to a set more in line with your cam grinders specs / recommendations.
IF they are within spec for your cam, follow the advice to get the push rods mentioned above - cheap insurance in my opinion . . .

Doc

[Jeff Kleiner]

Also check for spring bind. If you still have the rotators on exhaust valves bind is quite possible given that the Stage 1's .318 lobe lift combined with 1.7 rockers becomes .542 at the valve.

Jeff