I ordered a set of these Teflon Encapsulated O-rings from McMaster-Carr for
my 20B.  These things are very expensive, and when I tried to install the oil
control rings, I was not able to get them down into their grooves with these
o-rings on!!!  They look like the correct size but they are VERY stiff
compared to the originals.  I was unable to compress them enough to work.
They were destroyed during the installation.  Any installation ideas guys!!!

Thanks,
Don

Sorry about that Don. I have no personal experience installing them other than o
ne
time. I was dumb enough to install the cast iron oil scraper with out the spring
.
That is a real No No as you must then break the cast iron scraper to get it out.
I agree. They are not easy to install. Perhaps we need to machine an installatio
n
ring similar to a piston ring compressor or a large hose clamp.

I am hoping we can find a lube that will work. Most O-rings need a lube of
some kind when you install them in concentric tubes such as the oil control O-ri
ng
set up. Same goes for the neoprene O-rings in the wiggins couplings.

How many did you destroy? I just bought four big ones  for Perry's inner cooling
O-ring and they were about $10 apiece. How much were the smaller TES oil O-rings
?
Sounds like you are the first to try them. Hang in there Don. Its going
to be worth it.

Paul Lamar

Ken Powell wrote:

Don,
Which orings did you have trouble with?  I installed the outer oil control oring
(teflon encapsulated) without a problem.  I am still looking for the correct
inner oil control oring.  Here are the details on the oring that worked:
Outer oil control oring
part # = 9319K221  asa568a-158
qty = 4,  price = $7.17 each

Ken Powell

BTW the stock inner coolant TES O-rings from McMaster Carr are a bit too small
in diameter. You will have trouble getting them to stay in the slot when
assembling the engine.

Also Teflon has a memory so the rings take the shape of whatever package
they are shipped in. 

I came up with this solution. I cut a piece of 3/4 inch plywood the exact
size of the slot  and I stretched the rings over it for a few days so they come
out the exactly right size and lie flat in the groove.  

Paul Lamar
 
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