R90/6 Oil Leak Help

Discuss all things 1970 & later Airheads right here.
Major Softie
Posts: 8900
Joined: Tue Aug 03, 2010 1:46 pm

Re: R90/6 Oil Leak Help

Post by Major Softie »

Patdabin wrote:
Duane Ausherman wrote:You can easily tell if the oil is from the input seal of the transmission, or the rear main seal of the engine. They smell totally different. It could be both.

Removing the transmission will show the oil washing down the front of the case, or not. There are other very small possibilities too. Does the clutch slip?
No not that I know of. I will need to separate the two and see. I am debating installing not clutch plate while open.
What are some other things I should be doing to the bike while I'm at it. Maintenence or just time repairs. Timing chain?
Spline lube.
MS - out
User avatar
SteveD
Posts: 4909
Joined: Tue Aug 03, 2010 3:29 am
Location: Melbourne, Oz.

Re: R90/6 Oil Leak Help

Post by SteveD »

If you do the RMS...this might help.

Airhead Rear Main Seal removal and replacement.
Parts:
• Rms. Teflon pn 11-11-1-338-342
• Oil pump o-ring
• guide ring o-ring (clutch carrier models)
• 5 x flywheel bolts
• 6 x clutch bolts
• 4 x output shaft bolts
• clutch plate if there are any signs of radiating cracks
• consider new clutch centre plate.
• consider new neutral switch

Technique.
Preparation. Getting to the RMS.
1. Remove battery negative lead from the battery.
2. Remove the front engine cover.
3. Block the crank to prevent any forward movement.
4. Remove the gearbox.
5. Remove the clutch, trying to keep it as one unit to avoid later confusion at reinstallation.
6. Remove one of the bolts and take it to a hardware store to buy 2 longer ones. Then remove another bolt directly across from the first one. Screw in the 2 longer ones. Now back out the rest of them. Lastly, evenly back out the remaining shorter bolts.
7.
At the flywheel (clutch carrier)
1. Flywheel to TDC, OT mark. Mark it against the engine casing.
2. Securely fasten the marked flywheel to the case before undoing the flywheel bolts
3. Remove and discard the bolts. Remove the flywheel.
4. The cap, or "guide ring", used on the 1981+ models (the clutch carrier fits to it, the guide ring is over the crankshaft) and has a center lug to enable it to be pulled rearward by a factory tool. To replace a main seal on a 1981 and later, you have to remove the guide ring first. You can improvise. You can use a flat punch to rotate the ring until some of each crankshaft hole is covered, then pry to the rear....use a small screwdriver or similar, pry a bit on each hole/guide ring.


Installation.
The RMS must be installed square.
There area two types of flywheel (or clutch carriers) in use. If the front end has a small radius, then the seal is installed to full depth. If there is a taper, as on early flywheels, then the seal is rearward a small amount, about 1 or 1-1/2 mm. Oak uses rear ring gear shims for
that, installing the shims, then the seal.
Be sure the 5 holes in the guide ring are exactly aligned with the crank holes.

The installation tool.
http://www.gunsmoke.com/motorcycling/r1 ... index.html

Torques:
/7 11mm bolts-flywheel bolts were previously at ~75ft-pounds (100 Nm), they were now to be at 80-90 ft-pounds (125 Nm),... first you cleaned the threads and then the threads were to be slightly oiled
/5 & /6 10mm bolts require much less torque.
Oil pump cover hex head bolts- 88 in/lbs (7.3ft/lbs.
Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/R100RS
2006 K1200R.
1994 R1100GS.
Patdabin
Posts: 27
Joined: Sat Mar 19, 2016 10:50 pm

Re: R90/6 Oil Leak Help

Post by Patdabin »

Where is everyone getting their parts from in the states as I can find but one place that's Chuck in Florida?
Kurt in S.A.
Posts: 1647
Joined: Tue Aug 03, 2010 12:08 pm

Re: R90/6 Oil Leak Help

Post by Kurt in S.A. »

Recent thread here:

viewtopic.php?f=1&t=9631

Kurt in S.A.
Patdabin
Posts: 27
Joined: Sat Mar 19, 2016 10:50 pm

Re: R90/6 Oil Leak Help

Post by Patdabin »

Kurt in S.A. wrote:Recent thread here:

viewtopic.php?f=1&t=9631

Kurt in S.A.
Hello yes thank you for the link
Patdabin
Posts: 27
Joined: Sat Mar 19, 2016 10:50 pm

Re: R90/6 Oil Leak Help

Post by Patdabin »

SteveD wrote:If you do the RMS...this might help.

Airhead Rear Main Seal removal and replacement.
Parts:
• Rms. Teflon pn 11-11-1-338-342
• Oil pump o-ring
• guide ring o-ring (clutch carrier models)
• 5 x flywheel bolts
• 6 x clutch bolts
• 4 x output shaft bolts
• clutch plate if there are any signs of radiating cracks
• consider new clutch centre plate.
• consider new neutral switch

Technique.
Preparation. Getting to the RMS.
1. Remove battery negative lead from the battery.
2. Remove the front engine cover.
3. Block the crank to prevent any forward movement.
4. Remove the gearbox.
5. Remove the clutch, trying to keep it as one unit to avoid later confusion at reinstallation.
6. Remove one of the bolts and take it to a hardware store to buy 2 longer ones. Then remove another bolt directly across from the first one. Screw in the 2 longer ones. Now back out the rest of them. Lastly, evenly back out the remaining shorter bolts.
7.
At the flywheel (clutch carrier)
1. Flywheel to TDC, OT mark. Mark it against the engine casing.
2. Securely fasten the marked flywheel to the case before undoing the flywheel bolts
3. Remove and discard the bolts. Remove the flywheel.
4. The cap, or "guide ring", used on the 1981+ models (the clutch carrier fits to it, the guide ring is over the crankshaft) and has a center lug to enable it to be pulled rearward by a factory tool. To replace a main seal on a 1981 and later, you have to remove the guide ring first. You can improvise. You can use a flat punch to rotate the ring until some of each crankshaft hole is covered, then pry to the rear....use a small screwdriver or similar, pry a bit on each hole/guide ring.


Installation.
The RMS must be installed square.
There area two types of flywheel (or clutch carriers) in use. If the front end has a small radius, then the seal is installed to full depth. If there is a taper, as on early flywheels, then the seal is rearward a small amount, about 1 or 1-1/2 mm. Oak uses rear ring gear shims for
that, installing the shims, then the seal.
Be sure the 5 holes in the guide ring are exactly aligned with the crank holes.

The installation tool.
http://www.gunsmoke.com/motorcycling/r1 ... index.html

Torques:
/7 11mm bolts-flywheel bolts were previously at ~75ft-pounds (100 Nm), they were now to be at 80-90 ft-pounds (125 Nm),... first you cleaned the threads and then the threads were to be slightly oiled
/5 & /6 10mm bolts require much less torque.
Oil pump cover hex head bolts- 88 in/lbs (7.3ft/lbs.
Where do I get the tool from Gumsmoke?
Also If I buy a engine gasket kit will it com with all gaskets needed to do such work about.
And yes I know the bolts are not included.
User avatar
SteveD
Posts: 4909
Joined: Tue Aug 03, 2010 3:29 am
Location: Melbourne, Oz.

Re: R90/6 Oil Leak Help

Post by SteveD »

http://www.cycleworks.net/

When you buy an engine kit, you'll need to clarify with the seller if it's all there.
Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/R100RS
2006 K1200R.
1994 R1100GS.
Rob
Posts: 3088
Joined: Thu Feb 13, 2014 2:05 am

Re: R90/6 Oil Leak Help

Post by Rob »

Patdabin wrote: Where do I get the tool from Gumsmoke?
I always used an appropriate sized piece of PVC from the hardware plumbing department.
Just take the seal to the store with you.
Rob V
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