Main Seal/Gasket Gone or OK?

[kfz]

Watdoyerthink,  Main seal gone? worth pulling the flywheel off to see if the seal has gone.  Bike is 1000s with 70K miles on clock (30+ years old). 

Has the main seal gone or is this just normal grimey grease from the hub.  Front plate is a bit slimey,  No noticable drip from bellhousing but slightly damp on the inside.  normal???  Do it anyway its 30 years old?

Clutch was not slipping by the way, took it apart cos it was dragging.

Kev

[John A]

More likely the cam plug leaking. Pull flywheel, degrease area and seal with something better than  silicone . Some use JB weld.  One I sealed was being heated with a paint stripper heat gun to help degreasing and when the block was warmed, the plug could move around a surprising amount . With a small ball peen hammer, I peened the edges which helped some. Didn’t leak after sealing it .

[GeorgiaGuzzi]

More likely the cam plug leaking. Pull flywheel, degrease area and seal with something better than  silicone . Some use JB weld.  One I sealed was being heated with a paint stripper heat gun to help degreasing and when the block was warmed, the plug could move around a surprising amount . With a small ball peen hammer, I peened the edges which helped some. Didn’t leak after sealing it .

A picture of how I sealed my cam plug as John A described.

[kfz]

Just had a good look at the plug with with the torch flashlight   and I can see engine oil pooled in the webs around the plug.  Guilty. May change the seal anyways me thinks.  bike is in semi retirement now, so likely to dry out. the seal.

Kev

[kfz]

So the cam plug and the breather gasket look very oily.

[kfz]

A picture of how I sealed my cam plug as John A described.

Looks a bit heath robinson. As long as it works...

[guzzisteve]

So the cam plug and the breather gasket look very oily.

Swap out gskt, do it all once & be done w/it. I've done a bunch cam plugs w/JB weld. Clean & oil dry is key for it to work.

[John A]

Swap out gskt, do it all once & be done w/it. I've done a bunch cam plugs w/JB weld. Clean & oil dry is key for it to work.

Oil dry is a key point,  I use lacquer thinner which is a better oil solvent than acetone. Either will kill the main seal so it’s good to replace that after.

[kfz]

Oil dry is a key point,  I use lacquer thinner which is a better oil solvent than acetone. Either will kill the main seal so it’s good to replace that after.

Yep, agreed may as well do the old oil seal, breather gasket while im here.  Thanks John.

I think there is also oil getting past the breather hose and down the gap between the housing the spigot.  Not helping.  Replace the hose and silicon it witha decent clamp.

[moto-uno]

  I wouldn't be adverse to changing the seal and "o" rings behind the clutch hub also .  Peter

[Dilliw]

  I wouldn't be adverse to changing the seal and "o" rings behind the clutch hub also .  Peter

You took a journey to get there; I'd would look some more.  I think Wayne pressurized my motor with some air the 2nd time and figured out it was the o rings.

[John A]

Does that 1000S have a ten spring clutch ? What discs are you going to use? Just curious

[kfz]

Does that 1000S have a ten spring clutch ? What discs are you going to use? Just curious

No its the normal eight.  Plates?   Just the normal Surfex rivets ones.  They are in spec but cos its been dragging are a bit worn. 7.6mm , min 7.5

Kev

[kfz]

Does that 1000S have a ten spring clutch ? What discs are you going to use? Just curious

I rebuilt the box a few years ago with new seals, ,hig cap bearings and shimmed up drum.  Nowt wrong with the box one of the best ive done!

[Wayne Orwig]

You took a journey to get there; I'd would look some more.  I think Wayne pressurized my motor with some air the 2nd time and figured out it was the o rings.

Yes, the EV Valdez.





Yours was the gasket under the bearing carrier. I had to pull my transmission a few months back, and went after a bit of a leak. It definitely was the gasket under the bearing carrier.

I have been in there a number of times on bikes thinking they have a rear seal leak. It is almost always something else in there, not the seal. But if I am that close to the seal I still replace it.

[kfz]

Yes, the EV Valdez.





Yours was the gasket under the bearing carrier. I had to pull my transmission a few months back, and went after a bit of a leak. It definitely was the gasket under the bearing carrier.

I have been in there a number of times on bikes thinking they have a rear seal leak. It is almost always something else in there, not the seal. But if I am that close to the seal I still replace it.

Wayne,  How hard is it to replace the carrier gasket.  might just do that as well.  Can you do it without disturbing the crank?

Kev

[Wayne Orwig]

Wayne,  How hard is it to replace the carrier gasket.  might just do that as well.  Can you do it without disturbing the crank?
Kev

I do not have the special puller, so it is a real pain in the butt.
And I have been told, if you do have the puller, it is still a pain in the butt.

You have to be extremely careful, or you can break off one of the 'ears' that the screws go into. I have a large 'crows foot' that I go around and around prying on it. It is a slow process to get it the first 1/4 inch. If I did it a bit more often I would try to make or buy a puller. But the puller only grabs two 'ears', so it alone is not enough either. I have heard that the puller can break the 'ears' off easily also.

Probably not the best, but I always just let the crank stay in place hanging from the front bearing. Never been an issue for me.

On my EV that I just did, the gasket was pushed out a bit and leaking. I had replaced that very gasket probably 50,000 miles earlier, so I damaged it or screwed something up, I assume. Not the thing to do with something buried that far in. And Dilliw's leak just appeared. No idea why that gasket just decided to fail.

[Tom H]

From one who did break an ear off the bearing.

I did not have a puller, I used 2 set screws into the block and two bolts threaded into the bearing. The set screws give the bolts a place to push against.

I would not try to just pull the bearing if the engine is still in the frame. Once the bearing is removed, the crank will drop a bit. The crank will need to be supported so that it stays centered for the bearing to go back in.

If it was me, I would leave the bearing gasket alone if it's not leaking.

The seal for the bearing can be done engine in frame. Just be careful not to scratch the crank when you pull it out and make note of how deep the seal is in before you pull it out.

Tom

[kfz]

Thanks Guys,  you've successfully talked me out of it.  I have no evidence its leaking.

[Tom H]

Before you put it back together.

You could pressure test the bearing gasket. You need a compressor and some soapy water. With everything in the bell housing together, pull the dipstick and put the blow gun in there with a rag wrapped around it to seal it. Add some air and slather the soapy water around the bearing gasket and all you want to check looking for bubbles, No bubbles, good sealing.

Tom