Any opinions on what may have caused this?

-
Les Gibson

Les Gibson

FABO Gold Member
FABO Gold Member
Joined
Aug 5, 2019
Messages
643
Reaction score
1,016
Location
Sabattus, Maine
Found the #1 intake pushrod in this condition after a run. The rocker, adjuster and lifter all look okay, which surprised me. No indication as to what caused it. The mangled end is the rocker end.
20211010_163544.jpg
received_563052851584618.jpeg
received_203501011889579.jpeg
received_288293096248918.jpeg
 
Hit a valve ?

Get a bore scope and look in the spark plug hole and see if there is a mark on the piston.
 
Solid or hyd roller? What was the diameter and wall thickness of that pushrod?
 
Cut that pushrod off clean and measure the thickness.

I’d want at least .080”, and it should be heat treated.

Could be too much press with the insert which caused a split.
 
Les Gibson said:
I'll see if any of my racing buddies have a bore scope. Easiest way to find out.
Click to expand...

I got one off eBay for $7.00, USB for my lap top and it works great. I didn't think it would work being that cheap but it is fantastic, I use it all the time.
 
PRH said:
Cut that pushrod off clean and measure the thickness.

I’d want at least .080”, and it should be heat treated.

Could be too much press with the insert which caused a split.
Click to expand...

That's not .080, the last ones I made for a 440 were Crane and maybe .080 they were 3 times as thick as those.
 
Iv had that problem before in my race engine it was something wrong whid the heat treat
 
Pushrod looks kinda cheap...W2 setups are not something you want to skimp on pushrods. I'd put as big of a pushrod in there as you can get, double tapered if possible...just my 2c
 
replicaracer43 said:
Pushrod looks kinda cheap...W2 setups are not something you want to skimp on pushrods. I'd put as big of a pushrod in there as you can get, double tapered if possible...just my 2c
Click to expand...
I've already ordered a new set from Smith Brothers, 3/8 chrome moly with .120 wall thickness. That's what my engine guy recommended.
 
Could be simply a failed push rod.
 
The ball/tip came off.
Happened to me, 2 or 3 pushrods..ball ends came off at the lifter. I was unbelievably lucky that the ball ends landed on the valley and didn't get home run'd by the counter weights through the block or into the cam lobes.
Some companies, for a min.. some still do.. electro weld the ends on... bad idea.
I lost a cam lobe from the lash opening to 1/4 and the lifter slamming it over in over
 
You should be using a single taper 3/8-7/16 pushrod in that. Adding wall thickness is only a small increase in strength.
 
Yes. I've lost a couple weld on balls with way less spring pressure. Not a fan. Went with press on tips never a problem since.
 
Man I hate roller lifter that have the tie-bar on the outer side of the roller lifter. Is there any chance they hit the side of your block, I see the pushrods are close to the V on the lifter bar with W2 offsets. Are they clearing. Any chance of tight valve guides??? What’s the open spring pressure?
 
pittsburghracer said:
Man I hate roller lifter that have the tie-bar on the outer side of the roller lifter. Is there any chance they hit the side of your block, I see the pushrods are close to the V on the lifter bar with W2 offsets. Are they clearing. Any chance of tight valve guides??? What’s the open spring pressure?
Click to expand...
Yes, they appear to have plenty of clearance, I see no evidence to indicate otherwise. The heads were inspected back in the spring and everything looked good. Unfortunately I don't know what the open spring pressure is off the top of my head. I think I have the specs, I'll have to find them. I really think this was just a bad push rod that just eventually failed. I haven't found any other damage.
 
You must log in or register to reply here.
-

Back
Top