I would not trust a standard Garlock style seal above 2 pounds. You can do
better.
You can install 2 half width Garlocks. You can install a 2 way seal that
has lips facing in and out. You grease the void between the lips, so both seals
live a long time and no dust can walk under the sealing lip (inside lip) and
fail it. It is not tyipical for a properly installed seal to leak anything at
all. The higher the leak pressure the more tightly the lip grips the shaft
causing a short life
. You can push the seal out of the hole with too much pressure. You can
turn a lip seal inside out with too much pressure. Some seals have springs that
assist the lip in gripping the shaft. These are used in very dynamic
applications like gear boxes.
Gear boxes should have close to zero pressure. Any pressure must be
subtracted from the supply pressure, which is usually low to start with.
Seals in aluminum tend to be too loose a fit at high temperature, and
although there is seldom a problem with leakage I clamp Garlocks in place with
10-32 screws and small bent washers. You can also lay a bearing shim over the
garlock and use flat washers. It looks better. Same for plain bearings, like in
tailshaft housings. Even with oil coolers a bushing will often spin up and hose
the tailshaft casting. So I put a screw through them.
You can add a very thin "O" ring in the bottom of the seal well that can
seal against the chamfer on the outer corner of the seal, but you must clamp the
seal in against this "O" ring
for it to work.
And as ghastly as it may seem, you can lay in a very small bead of non
hardening Permatex
sealant on top of that "O" ring. You need not tell anyone that you did
this.
There is no shame in using a seal in good condition over again. Just check
to see that the lips are still flexible.
In olden times when junk engines were raced every weekend I would shorten
the spring on the rear seal of my rotary to keep the oil inside the engine that
had so much blow by that we emptied the catch can back into the engine after
each session.
Lynn E. Hanover
In a message dated 10/24/2011 9:09:00 P.M. Paraguay Daylight Time,
echristley@nc.rr.com writes:
The
question I have is do I need to replace the front and rear oil
seals. I pressed the front oil seal back in, and even
added a couple of
retainers, as Lynn has suggested; but, should I
replace it with new
one, even if it doesn't leak? I put a rubber
hose over the oil inlet,
and blew into it. I could hear it bubble
out of the rear seal when I
covered the oil outlet. How much
pressure should those rubber seals be
expected to
contain?