Installing JE Piston Rings
 

Since JE won't be answering any questions until Monday, I figured that I'd ask here first...

For my 85 mm JE piston rings, I've got two compression rings:
- 1 almost black, with a dot on one side and a bevel on the inside, on the opposite side from the dot
- 1 not as dark, no dot but a bevel on the inside edge

Does anyone know...
1) Which is the top ring?

The instructions are pretty clear that the ring with the dot is installed dot side up, while the ring with the bevel is installed bevel side up.

Thanks.

are they all the same thickness? usually thinnest is top but they should match the grooves

my Ring package is 1.2 top ring, 1.5 second ring, 3mm oil ring

Hi John;
Both compression rings were 1.5- mms.

I just got off the phone with EBS where I bought them and they said that the lighter (brownish) rings were chrome top-rings, which were mounted bevel side up. The black rings with a dot were reverse-twist 2nd rings which were to be installed with the dot up.

Interesting, their website doesn't show that combo, only a ductile top 1.5 and an iron second 1.5-- another way to tell them apart is the radial width-- top is .141" and second is .157 or .150".

Search for J640F1-3347 or J640F4-3347

I had to look up "reverse torsional"-- couldn't find it on JE but one souce says:
Torsional Twist: A built-in imbalance between the way the upper and lower sides
compress that causes a twist in the ring when compressed. Used to seal both the ring in
the groove and the ring to the cylinder wall.

Good research John. I've got the J640F4-3347 rings. It looks like I need to take apart the one set that I've assembled and put them in the right way. It's good that I asked.

John,

I looked at their catalog-- the dots definitely go on top but both top rings and second rings can carry a dot.

The second ring should be identifiable because of the trapezoidal shape-- that's the "reverse torsional" cross-section. You can kind of see it in the picture. They don't list all the part numbers but it's pretty clear from their catalog what they mean-- J640 is the ring series, F is the tension (standard), 4 is number of cylinders (you probably have a box of four as a set and then two extras like I do) and then the last four digits are the bore in decimal inch-- 85mm x 25.4 = 3347. So J640F4-3347. And if you go to www.jeproseal.com and punch in an 85mm bore and look for sets it gives you .141 for the top and .150 for the second in that set.

Good luck, I hope it's not confusing when I go to do it, but all my rings are in plastic marked "TOP" and "SECOND."
http://forums.pelicanparts.com/uploa...1194298479.jpg