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Thick C-CLIP piston pin installation
bikecarbfred - 29/1/18 at 07:33 AM

I am finding it impossible to install a c-clip that secures the gudgoen pin in the piston.


their wire type and around 1mm bleeding thick so they have no hole in them so I cannot use a cir-clip pliers.

ive wasted a day. I even bent one slightly with normal pliers but not to the point it wont be effective



i cant find any suitable tool. thire wire so keep sliding out of pliers. nothing to grip them from.



all the youtube tutorials make it look easy as their clips are way much thinner, you can bend them by hand.

But these Kolbenschmidt ones are impossible. I have wedged screw drivers in ,twisted but can't be done due to the sheer force required.

How would an engineer shop do it. Is there a tool where you can slip the wire into?


Theshed - 30/1/18 at 09:02 AM

You normally just wind them in. Put in the first leg and then work your way around using a bit of aluminium to push the clip into the groove. Use masking tape all over the piston to protect it against slipping.

If the clips are stronger than that then you could use a tapered tube to install them. However on the engines I use (full race with JE Pistons) they expressly tell you not to do that and recommend the method above.


Theshed - 30/1/18 at 09:04 AM

I would add that I seriously would not contemplate using a bent c-clip. They will cost £1 or less and the consequences of one falling out would be somewhat more.....


bikecarbfred - 30/1/18 at 10:19 PM

I have got them in after a car mechanic showed me how to do the first one.

I did use one that was slightly compressed (bent) but it will be impossible for that to pop out. I have even tried to slide it around with a screw driver and it won't budge. and just where there is an indentation to place a screw driver you can see the c-clip sitting flush against the wall.


If it was more compressed/ bent than I thought I would not have used it.


ReMan - 31/1/18 at 08:01 AM

How were you shown? As above? With needle nose pliers to start it ?
Glad you got done!


bikecarbfred - 31/1/18 at 08:37 AM

@Reman

I was shown by using a really thin flat blade screw driver to get around the clip , turn the screw driver 90 degrees against the recess wall and it popped the other side of the c-clip in.

@ all others in this thread


I ended up taking out the bent c-clip as I noticed it was not fully perpendicular to the radius of the grove. Bent one below.



So I had a set of older pistons, about 60,000 miles on them.

I used one of the c-clip from one of those. I know your supposed to use new, but the old one was fine and not bent, the tension was the same, and the distance of the gap between the clip ends was the same as the new ones.

I put that in (were just as hard to get that in) and now it looks like all the others.

These wire type c-clips measure 1.5mm thick.

[Edited on 31/1/18 by bikecarbfred]

[Edited on 31/1/18 by bikecarbfred]


Theshed - 31/1/18 at 11:57 AM

Good decision! There is a lot or force on a piston. You would never have been able to drive the car hard without wondering ...what if...


snapper - 31/1/18 at 06:07 PM

I fitted a set of round clips in Kolbienschmit pistons on Cosworth rods but was told square groove square clips round grooves round clips.
I left the round clips in the square grooves as they were a good fit, 1.5 mm round into 1.5 mm wide groove that is 0.75mm deep


bikecarbfred - 31/1/18 at 07:22 PM

@snapper

some would say that is insane. although i would not do that but it depends on the type of clip

some clips are super skinny and can bend with your fingers with ease. with those you would think the margin for error is lower.

these thicker springs have so much tension/spring.