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View Full Version : Trick to Piston Pin retainers?



kconnair
02-09-2007, 18:13
I am in the process of assembling my engine, and I ran into a small issue....

Is there a relatively easy to get that heavy wire retaining clip into the grove?

On other engines with snap rings, I have used snap ring pliers.....

Thanks,

Kevin.

john8662
02-09-2007, 18:47
oh the joys...

Yeah, just start by inserting one end into the groove, then roll the retainer in with your thumbs. You'll need to use one thumb to help hold what you've already gotten in, while using the other thumb to guide the rest in.

At about 3/4 the way in you'll find it gets easy and will snap right in.

Kinda a pita though, at first that is.

J

kconnair
02-09-2007, 21:48
Thanks John, Figured it out... pretty much the same way you suggested.... I used a hard plastic probe to help work it in...

Kevin.

john8662
02-09-2007, 22:16
Yeah, my thumbs usually hurt a bit after that lovely chore, the plasic probably helps that a bit.

I'm looking forward to some good callus' in the future, no more feelin'

:D

J

ronniejoe
02-09-2007, 22:50
I don't like doing it that way because of the risk of injury. I've found a better way is to insert one end into the groove as John said and position the other near the removal slot. I then hold the first end in place with my thumb and grasp the free end with a pair of needle nose pliers and gently wind it into place. The needle nose pliers end up being inserted into the removal slot to finish.

This method works pretty well, as long as you're careful, and minimizes the risk of injury. Also, be sure you wear safety glasses!

gmctd
02-10-2007, 00:01
I use similar to ronniejoe, with smooth jaw pliers so as not to nick the spring clip

BTW, kc - I can't quite make out your avatar - is that a Vega 140 four with two webers?

Maybe a Cosworth?

kconnair
02-10-2007, 07:26
140 with dual dcoe Webers :) - Good eye.

arveetek
02-10-2007, 09:41
Also, be sure you wear safety glasses!


Yes! It's really annoying to have one of those clips spring loose and go flying across the shop. It's quite another thing to have one come loose and go flying into your eye!

Casey

Robyn
02-11-2007, 09:12
Just an observation here

Years ago it was determined by many racers that the best place to put the gap on the retainer ring was either top or bottom and not on the side.
The theory is that under some conditions that ring can begin to become sympathetic to the piston motion and jump out of the groove.
I have seen two 6.2's and one 6.5 with wrist pins through the cylinder walls.
Too far gone to really figure out what happened other than the ring was gone and the engine was toast.
I always install the opening at the bottom facing the rod.

Just a thought on the subject

Robyn

gmctd
02-11-2007, 10:47
Yep - gap facing the crank puts the mass across the upper groove, where the combustive thrust forces the clip-ring into the groove