Broken Pushrod...

[Anonymous]

Anyone ever have this happen before to them??

It happened around 6 grand in 1st gear.....thought I blew the motor up when it let loose! :x

Its a Clifford chrome moly pushrod. Sorry the picture sucks but it sheered the top completely off the pushrod and cracked it in half also. After further inspection, another pushrod had a crack running down the side of it but it hasnt broke yet.

I swapped back to my stock set until my jet hot parts come in and Mike can send me a set with my other stuff!

I've had these pushrods for about 4 years and I'm running roller rockers....Maybe fatigue from all the years of abuse??

Thanks,

Doug

 

[STEVEN.]

'M-G',That's kinda amazing to see,a broken pushrod like that. I've seen 'em bent,gouged,twisted,and so on,but never like that. I'm glad everything turned out Ok for ya. I can't imagiane what it would've been like for ya if you grenaded the poor thing........proabably would've hit the roof.........and right before ya got your other stuff in :x . It's kinda hard to belive that they were ONLY 4 years old. Who made them? When you say "abuse",what kinda "abuse" we talk'n about here ? You got a cinderblock tied around your left foot or somth'in ? OO6./The-X-Or-Six!

 

[Anonymous]

Geezer,

That's a ball & cup pushrod, I thought with roller rockers you would use ball/ball push rods? If the flat surface of the roller was riding on the lip of the cup it may have caused this failure, just a thought.

 

[addo]

Doug, you're a great test pilot. Anyone who runs things until they actually bust, should be an honorary Aussie! (Kiwis then fix it with baling wire and run another 80K miles.)

Looks like one of those "DIY" pushrods where you cut to length and press the end in. Service life issues? For one to fail and another crack, it's likely not the installation, but the application that's at fault. The only slight possibility is interference with the rocker arm material or side of the rocker "ball", which would be visible.

Adam.

 

[Anonymous]

Steven,

. Who made them? When you say "abuse",what kinda "abuse" we talk'n about here ? You got a cinderblock tied around your left foot or somth'in

Clifford Performance made them and my abuse is 1000's of high RPM shifts and hundreds of burnouts!

Don,

The roller rockers use a ball & cup pushrod...when I get my new pushrods, I'll see if there is any interferance on the rocker arm but I never noticed any before. The pushrods I've run since 2000? and the roller rockers since 2001 IIRC.

Adam,

No since fixing it until its broke! It seems to be getting lots of oil to the rocker arms....I'm thinking they just finally wore out! I am also running Cliffords double valve springs so they are under increasced pressure from stock.

I'll see if I cant get a slightly better pic of them tonite.

Thanks!!

Doug

 

[addo]

Hey Doug,

There is a Crow piece that is a single spring rated through 5500RPM and to 530 thou lift. It might be a better unit (less loading)? Just a thought - I hate the idea of wasting "energy" on a spring too stiff.

Adam.

 

[wsa111]

Doug, is the ball end of the adjuster on the rocker arm show any wear. The cup on the pushrod looks like it is worn through??? its hard to tell from the pictures. Just double check.
Normally the cup just breaks off from the spot weld to the pushrod.
I would get the new set of pushrods from mike in very shortly.
The clifford double springs have about 120# seat pressure, so i know valve float was not the problem.
Good luck on your repairs. william

 

[Anonymous]

Doug, when you built this last motor did you use clay to check piston to valve clearance? One way to bust a push rod like that is if the piston and valve come into contact with each other something has to give, rocker arm, pushrod something.

Unless your positive of the clearance and timing I would check for bent valves and cracked rockers as well.

Usually the ball/cup push rods go with adjustable rockers while the ball/ball push rods go with non-adjustable rockers.

 

[MandarinaRacing]

Addo wrote:

Doug, you're a great test pilot. Anyone who runs things until they actually bust, should be an honorary Aussie!

Doug, have your doctor look at your right foot, there might be a high LEAD content in it!!!!!!!!


Alex

 

[Anonymous]

This has been bugging me, I deduce from the fact that you are using standard Clifford chrome moly pushrods that you have roller tip rockers not the oil through design used with the full roller rockers. The only thing I come up with is possibly the fit of the round adjusting screw in the ball. Maybe you could compare one of your roller tip rocker adjusting screw ends to one from a stock Ford adjustable rocker assy. If it's not the ball end of the adjusting screw then it might be the cup end of the pushrod. If you can get a-hold of them you could compare different brands there also. Just a thought.

 

[addo]

Doug, have your doctor look at your right foot, there might be a high LEAD content in it!!!!!!!!

As long as he never puts it in his mouth, it'll be fine.

 

[Anonymous]

LOL Addo

 

[ricksmol]

Doug:
Didn't you have either the adjusting screws or the pushrod cups machined by Gary at Rocker Arm Specialists? I haven't re-installed my set up because of an issue of radii difference between them.

Rick

 

[Anonymous]

Doug, have your doctor look at your right foot, there might be a high LEAD content in it!!!!!!!!

As long as he never puts it in his mouth, it'll be fine.

Rick,

You're right, I did have the cups remachined....after further thought, we think that weakened them to the point of having them split open after high RPM use....I'm going to install a set of Mikes pushrods and I'll keep you informed on how they work out!!

Thanks for all your guys opinions!!!

Later,

Doug