Identify pushrod damage.

[Dave Bilyk]

Noticed this neatly machined pushrod when I stripped my 302.
My guess is that the hydraulic tappet was sticking allowing the pushrod to move sideways and contact the guideplate.
Not worried since I am converting back to roller lifters, but wanted to know if that is a correct diagnosis, or if there are other reasons for this to happen.
Anyone had this happen / can answer this?

Dave

 

[Mike Huddart]

David,
CORRECT diagnosis is non-hardened pushrods with hardened guide plates, result, knackered pushrods, QED.
But you do have the correct ones now don't you.
Mike

 

[Randy V]

Mike is right - but another cause might be if you were using rocker arms that have guides built in that locate the rocker arm on top of the valve stem as well as guide plates. The two, used together can cause this.

 

[Dave Bilyk]

Mike, yes I am confident that I have the right ones now because they were supplied by a master engine builder, what's his name now? Hobbit or something similar:laugh:

It was only the one pushrod that was touched, which is why I suspect a sticking tappet, but non hardened pushrod vs hardened guides is clear as there is only the lightest touch on the guide itself compared with all that wear on the pushrod. Maybe there is a sharp edge on the guide that I should dress off too.

Randy, I see why that would be an issue, but I don't think I have built in guides, will check to be certain and have a look for marks in the rockers.

thanks guys

Dave