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toolmakeron 03-16-2014 11:36 PM

wrist pin clip issues
 
On a 632 Chev , 14.5 engine, we found some pieces of wrist pin clips in the oil change. They are 2- .042 spirolocks.(per side) They were not excessively stretched when installed.My first thought was a bad batch of heat treated clips. I was told that because he hit the chip in the water box, this will cause this kind of problem. Engine had about 60- 75 hits on it. He (the driver) also pedals it in the top end. car is a dragster, about 2100 lbs . I was told that this also might contribute to this problem. I get my info from drag racers that have 40 years in the game & I respect their knowledge. Any input or experiences that I can learn / understand whats going on ? His last engine pounded out the clip grooves to about .030-.035 end play. Same basic engine.Same car . Thanks guys

rickseeman 03-17-2014 11:14 AM

Re: wrist pin clip issues
 
Quote:

Originally Posted by toolmakeron (Post 424733)
On a 632 Chev , 14.5 engine, we found some pieces of wrist pin clips in the oil change. They are 2- .042 spirolocks.(per side) They were not excessively stretched when installed.My first thought was a bad batch of heat treated clips. I was told that because he hit the chip in the water box, this will cause this kind of problem. Engine had about 60- 75 hits on it. He (the driver) also pedals it in the top end. car is a dragster, about 2100 lbs . I was told that this also might contribute to this problem. I get my info from drag racers that have 40 years in the game & I respect their knowledge. Any input or experiences that I can learn / understand whats going on ? His last engine pounded out the clip grooves to about .030-.035 end play. Same basic engine.Same car . Thanks guys

There is something else going on here. Everybody in the country runs double spirolox ( which is way overkill) and doesn't have a problem and he pounds them out of 2 motors in a row? Something is way wrong.

toolmakeron 03-17-2014 06:11 PM

Re: wrist pin clip issues
 
yea I know somethings very wrong, but the" fun" ? here is how to avoid it next time.The driver won't listen to me & thinks it's the engine builders fault...isn't it always? LOL

pmrphil 03-17-2014 08:32 PM

Re: wrist pin clip issues
 
I've seen before when an engine is detonated hard enough it will bow the pins and push hard on the spirolox - overrev will do it also.

richie 2 03-19-2014 07:08 AM

Re: wrist pin clip issues
 
spark plugs would show signs of detonation?

toolmakeron 03-21-2014 01:02 AM

Re: wrist pin clip issues
 
I haven't seen the plugs, but I was told that it's hard to see signs of detonation from alcohol engines. I don't know this, only going from what I was told. The driver / tuner would see this , I think he would know about this. I keep suspecting , on the chip in the water box. Thanks for the input guys.

Adger Smith 03-31-2014 02:11 AM

Re: wrist pin clip issues
 
His alky tune up or his on & off throttle foot could be flooding the engine at some time in the run and never show up on the plugs. I'm still saying you have the combination of an abusive driver and a slightly off Alky tune up. I don't mean off at WOT. I mean off in the "Fuel Curve" when the foot is on and off the throttle.

Marine One 04-30-2017 02:12 PM

Re: wrist pin clip issues
 
Have you torn it down yet to inspect for damage?

Is the damage worse on one bank vs the other? Any specific cylinders consistently worse than the others?

On the non failed clips, do they or the piston grooves show any unusual signs of wear, like four corner wear vs even wear, etc?

cjperformance 05-02-2017 06:39 PM

Re: wrist pin clip issues
 
Hi all, 1st post here !
With this wrist pin damage issue, what are the rod pin bushings looking like?
Bush brand/material?
Coated pins?
AND pin/rod clearance?
I have seen where the pin clearance is too small and the pin nips in the rod, then any side movement of the piston is forcing on the pin clip and damages the clip and/or piston.

JMan 05-04-2017 10:33 AM

Re: wrist pin clip issues
 
I had one customers' engine that I tore down for a freshen up only to find multiple spiro loc failures. To the point of serious cylinder wall and piston damage. After digging for info I found out the previous assembler purchased his spiro locs in bulk from McMaster Carr. Needless to say the quality control ( heat treat ) may not be up to the quality of that of a Performance Piston company. I installed JE locks and 2 seasons later on freshen up, no more failures on a 700" .
I am not suggesting that that toolmakeron's engine has McMaster stuff in it, just sharing an experience*


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