Episan circlips

[Saw Dr.]

I was starting to build a 290 up today. I took the new Episan out of the box, and installed it on the rod. I had to clearance the area between the pin bosses, as it was too tight and binding. Then I installed the circlips. I HATE those ones with the "ears" on them. These particular ones were larger diameter than the OEM clips, so I could not use OEM. The outward tension seems very weak on these circlips. I always install the "ears" up on this type of a clip, so the power pulses force the heavy end of the clip (with the tang) INTO the groove. This also prevents any sideways stress on the tang, and hopefully prevents it from breaking off. The clips in this piston can easily be rotated by pushing with my fingernail. They are not tight at all. I'm concerned that they will rotate, wear, and eventually come out. Now what do I do? They are .020 larger than OEM clips, and the groove in the piston is the proper size for them. Maybe I need to take them out and bend them a little more open?

 

[Jacob J.]

Now what do I do? They are .020 larger than OEM clips, and the groove in the piston is the proper size for them. Maybe I need to take them out and bend them a little more open?

At the very least. I can honestly say though, they probably won't last.

You might think about getting the OEM clips for the MS-361 and going that route.

 

[Bowtie]

opcorn:

 

[Saw Dr.]

I'll look at the 361 clips. I had not noticed that they were thicker. My other thought was to cut the tangs off the Episan clips, and open them some on a tapered punch.

 

[nmurph]

I DO NOT Episan for that reason; their quality. I bought a Episan piston one time and the pin would not even fit in the piston. I ended up reusing the OEM pin. I don't remember about the clips.

 

[tlandrum]

id like to get ahold of some spiral locks that would fit in chainsaw pistons. then we'd never have to worry about it again

 

[Saw Dr.]

Well, the piston itself seems to be of decent quality. The pin fit into this one just fine. Too bad the rod wouldn't fit inside the piston.... I have a used 361 piston here, so I'll go do some trial fitting, and see how it works out. I hate to toss a brand-new piston that looks good.

 

[Dan_IN_MN]

I've got an AM piston, for my Jonsered 830, coming from a member here.......I'll keep an eye on this thread. I don't remember the brand of the piston.....

 

[Stihlofadeal64]

opcorn:

Sounds real familiar. I've been reading about this all week.
Time for some AS member to do some R&D and find a circlip
manufacturer or reasonable solution to this commonly reoccuring
problem!:bang:

 

[subhunter]

I used one in a 272 a couple weeks ago. The pin would not fit and I had to sand it out some to use it. Oem pin was around .040 shorter that the one the episan used. Also the two clips were definitely weak and one was even twisted to the point I wouldnt even consider it. I used oem ones and they fit nice and the quality of the piston overall was nice.

 

[Jacob J.]

The 290 pin is 10mm but the OEM clips are very thin, like the OEM clips for the 10mm wrist pin 044.

Episan has sized the clips for their 10mm wrist pins using the same diameter wire as that found in
regular 12mm wrist pin clips. The 361 pin is 11mm but uses a thicker clip, so it may work in the
10mm Episan groove.

 

[almondgt]

I was starting to build a 290 up today. I took the new Episan out of the box, and installed it on the rod. I had to clearance the area between the pin bosses, as it was too tight and binding. Then I installed the circlips. I HATE those ones with the "ears" on them. These particular ones were larger diameter than the OEM clips, so I could not use OEM. The outward tension seems very weak on these circlips. I always install the "ears" up on this type of a clip, so the power pulses force the heavy end of the clip (with the tang) INTO the groove. This also prevents any sideways stress on the tang, and hopefully prevents it from breaking off. The clips in this piston can easily be rotated by pushing with my fingernail. They are not tight at all. I'm concerned that they will rotate, wear, and eventually come out. Now what do I do? They are .020 larger than OEM clips, and the groove in the piston is the proper size for them. Maybe I need to take them out and bend them a little more open?

Bending the clips out is not an option IMHO. Weakens the part further. Appears to be issues in both the Episan and Meteor brands. Enough problems with the aftermarket pistons mentioned to keep me from using them. Find clips that are OEM or as good as OEM or I wouldn't recommend using the Episan piston.

 

[madrone]

If I have OEM clips available I've found it fun to take the aftermarket ones and tighten them on the needlenose till they fly.
It's feels good to do this on purpose for a change.

 

[Roanoker494]

Aftermarket wrist pin clips are all ready out there, even high performance clips. Do a Google search for 10mm wrist pin clips and you will find plenty of hits with the scooter racers.

https://www.google.com/search?q=wri....,cf.osb&fp=489a5df6753f2053&biw=1366&bih=636

 

[belgian]

At the very least. I can honestly say though, they probably won't last.

You might think about getting the OEM clips for the MS-361 and going that route.

Jacob, you remind me a lot about Lakeside. He had seen it all before and his comments were always spot on.

Back to topic : I ruined a good husky 262 top end with a episan circlip comin loose. Their pistons look really good imo but the circlips are of poor quality wire and don't have the correct tensile strength imo. I always re-use the original ones or go OEM now.

 

[bcorradi]

Jacob, you remind me a lot about Lakeside. He had seen it all before and his comments were always spot on.

Back to topic : I ruined a good husky 262 top end with a episan circlip comin loose. Their pistons look really good imo but the circlips are of poor quality wire and don't have the correct tensile strength imo. I always re-use the original ones or go OEM now.

I agree

I'd install OEM that work or don't install the piston IMO.

I installed a 1st gen 046 big bore kit on a saw i was going to keep for myself once and it didn't last long before the circlip launched.

 

[Scooterbum]

I always coat the circlip groove with red loctite, haven't had one launch yet.

knock on wood

 

[Saw Dr.]

Thanks for the replies guys. I would have already assembled the engine with OEM clips if they were the right size to fit the groove. I keep a stock of 372 and 290/51/55 size clips here. I am currently out of 046 size, and will be ordering some 361 ones while I'm at the dealer. Thanks for the great tip, JJ. There are a few applications where Episan is the only A.M. piston avail, and it is good to know how to make them work. Jonsered 920 comes to mind here, and likely 830 as mentioned earlier. Aside from the weight, the machining seems decent on them.

 

[madrone]

My new 090 piston kit from Baileys just went in and I couldn't use the OEM clips either. The grooves were just too small so I went with the aftermarket.
Never thought about loctite. Anyone else try this?

 

[Stihlofadeal64]

I always coat the circlip groove with red loctite, haven't had one launch yet.

knock on wood

Sounds like a free tip to me. Anyone have any more links and tips about the circlips. I have several saws on the
bench, and am getting more concerned as I read the posts. Is there any aftermarket pistons that have NO issues
with clip problems (It seems like all the major ones have been listed and at least one incident with each of them
which have clip launching problems). Just wondering