Wossner piston circlip orientation?

[dac69er]

Doesn't say anything about it in the instructions.
Which orientation should the gudgeon pin circlips be installed on on wossner forged pistons?

General consensus seems to be with the open end at either 12 or 6 o'clock, but nothing specific to wossner???

Any advice from any engine builders on here?

 

[gorganl2000]

to the best of my knowledge,,,as we did the build ourselves (a simple but very experienced mechanic and myself),,,we just focused on installing them securely into the respective grooves,,, no particular attention was paid to orientation,,,from 2017/2018 the engine is still running today

see what the professionals have to say

 

[dac69er]

I know it is more of a motorbike thing, more specifically 2 strokes, but thought I would ask.

I went with the open section facing upwards -ish.

Online it claims you can do it all with your fingers, maybe if you are a mountain climber!!!!

I'm sure it will be fine

 

[gorganl2000]

yeah, they were kind of fiddly to get into the groove, but quickly snap into place,,,so i would image a bit difficult to get exactly placed in each instance.

you should be good regardless

 

[dac69er]

Yeah, they aren't exact by any means. I used a pair of long nose pliers to tease them round into place. They aren't coming out in a hurry, put it that way

 

[Calum122]

@dac69er Yeah...I was going to say.

Generally you don't want the circlip open perpendicular to the stroke direction.

In other words, the open face shoud face the direction of the stroke, either up or down.

But as @gorganl2000 The main thing is that it is in securely!

The risk of fitting them perpendicular to the stroke is that it could compress the circlip under load enough for it to wiggle free.

 

[dac69er]

@dac69er Yeah...I was going to say.

Generally you don't want the circlip open perpendicular to the stroke direction.

In other words, the open face shoud face the direction of the stroke, either up or down.

But as @gorganl2000 The main thing is that it is in securely!

The risk of fitting them perpendicular to the stroke is that it could compress the circlip under load enough for it to wiggle free.

That is a fair point. Even though it is a pretty unlikely scenario, I've done them with the open section facing up(-ish) so should be good

 

[Franza1]

@dac69er Yeah...I was going to say.

Generally you don't want the circlip open perpendicular to the stroke direction.

In other words, the open face shoud face the direction of the stroke, either up or down.

But as @gorganl2000 The main thing is that it is in securely!

The risk of fitting them perpendicular to the stroke is that it could compress the circlip under load enough for it to wiggle free.

I can't see how this would be possible,

number 1 the clip isn't actually holding the wrist pin in place it's just restricting the movement of it.

Number 2 the only force that would be acting on the clip its self that would make it worth while thinking about would be that of the change in direction of the mass of the clip its self by the speed its traveling ( inertia ) which would be infetecemal ( less than .000001 of a kg of force) which if anyone has ever used a clip like this would know it takes alot more force than that to compress

The only force that I can see that would dislodge the clip its self is the wrist pin pushing it out and at that unless the pin is not installed in the Grove properly is also a force that I can see being met.

Main focus should be double or tripple checking they are seated properly. I'd arrange them all facing upwards anyway but to be honest that's only out of being overly particular.

 

[Calum122]

I can't see how this would be possible,

number 1 the clip isn't actually holding the wrist pin in place it's just restricting the movement of it.

Number 2 the only force that would be acting on the clip its self that would make it worth while thinking about would be that of the change in direction of the mass of the clip its self by the speed its traveling ( inertia ) which would be infetecemal ( less than .000001 of a kg of force) which if anyone has ever used a clip like this would know it takes alot more force than that to compress

The only force that I can see that would dislodge the clip its self is the wrist pin pushing it out and at that unless the pin is not installed in the Grove properly is also a force that I can see being met.

Main focus should be double or tripple checking they are seated properly. I'd arrange them all facing upwards anyway but to be honest that's only out of being overly particular.

I have only built high reving 2 strokes (max RPM 20K), I'm not sure if that would make any difference?