Pan Tranny Question (Main Drive Gear)

[amiabledave]

I AM REBUILDING A PAN TRANNY.......I have reviewed the DOCUMENTATION on this site, How To Wrench Your 74 Tranny. The only seals I see, IN THE DOCUMENTATION AND IN MY MANUAL, are a Cork Washer, Main Drive Gear Oil Seal outer and inner. Now the inner keeps oil from passing through the main shaft and the outer rides on the gear spacer.

QUESTION......WHY ISN'T THERE A SEAL/O-RING ON THE MAIN DRIVE GEAR, JUST IN FRONT OF THE ROLLER BEARINGS, THAT BUTTS UP TO THE BACK OF THE SPACER? IT LOOKS LIKE OIL WOULD GO OVER THE GEAR TEETH, ONTO THE ROLLERS AND SNEAK PASSED THE BACKSIDE OF THE SPACER, THEN UNDERNEATH IT (BETWEEN THE SPACER AND GEAR)

EVEN IF YOU PUT ON A SUPER NUT, OIL COULD PASS LIKE MENTIONED ABOVE AND COME OUT THE BACKSIDE OF THE CHAIN SPROCKET.

ALSO THE CORK SPACER, WHAT DOES THAT DO? PREVENTING THE MAIN GEAR SEAL FROM GOING DEEPER IN THE CASE? IT DOESN'T SEAL THE BACK SIDE OF THE SPACER, BUT ENCOMPASS IT.

Thanks for you time and support

[1950Panhead]

I wondered the same thing, here's a theory, the gear and the flange are in contact and act as a seal.
Jerry

[amiabledave]

I thought the same thing, trying to make sense of it. It would make better sense if the contact surfaces where ground true and parallel. Yes? So your saying that there is no other seal? I should go ahead and put it together?

[Dave_R]

Iv'e heard of some people taking the main drive gear to a machine shop and have a groove cut in for an O-ring. However, I have not done this and as long as the spacer and main drive gear surfaces are good, they don't seem to leak at all as long as the main sprocket nut is tight. Problems arise when the nut is loose.

As far as the cork behind the main seal, I always thought it was there to provide a "seal" between the case and the seals outside surface. Sometimes there is some leakage there with the origional seal design. However, if you are using a seal such as James with the blue rubber coating on the outside (as shown in 1950Panhead's picture), then you really do not need the cork.

A word of warning (I went throught this)....
Make sure that the seal is pressed in 0.050 inside the case and is square. If it is pressed only flush, then the little key that forces the main drive gear spacer to rotate with the sprocket will tear up the lip of the seal, causing a very BIG leak real quick!

[Bigincher]

Check out this article:

Finally a cure for the Panhead leaking transmission


Here's another one:

viewtopic.php?f=5&t=5803

[amiabledave]

Thanks you all for the response. I've asked shops around here the same question. H.D. Dealers have no clue and don't even work on the classic bikes ( the old time mechanics are long gone). The other shops that work on the Classics are scary at best (real horror stories...).

The tranny never leaked oil, so I would think that the gear and spacer mating surfaces are good (looking at them). I just raised the question, and it looks like others also, because by looking at it, it would.

I may use silicone between the spacer and gear. Also on the inner chain sprocket. It may not need it, but it's a piece of mind..

OH! I have a 1990 FXST Glide front end, need a part. H.D. Dealer said they are selling parts until the warehouse runs out then it's after market.

[Bigincher]

If your dealer is worth his salt, he will go on the national HD database and look for a specific part for you if he doesn't have it. If it's at a dealer anywhere in the US, it will show up. You'd be amazed at what's still on the shelves out there.... but then again, if it's not entered in the database, it just sits there on the shelf. And sometimes items are entered wrong. But I've bought 30-yr old parts before that way! Some of them are still out there!
My local dealer has a 'yard sale' every Spring, cleans out all the leftover crap. I've made some excellent purchases a time or two!
Also, for my modern bike, I always go to the Zanotti website and buy parts online. They are always considerably cheaper than the local dealer-- at first I was suspicious and called them and asked them how they can be so much cheaper than other dealers, are they selling real HD parts. They said the parts as the same as the other dealers sell, but they don't have to spend near as any man-hours on the internet sales--- just process the order, box the part and ship it.

http://shop.zanottimotor.com/" onclick="window.open(this.href);return false;

Oh, you need to know the part number that you're looking for, that's how the system is set up.

[amiabledave]

No salt in this area...I get the sense that no one wants to talk to you when you say Panhead......A Ford dealer bought 3 dealerships here for his son.......I don't know in your neck of the woods, but when H.D. was back logged on bike orders (10-15 yrs ago), to buy a bike here YOU HAD TO BUY a min. of $500.00 of accessories. Then the parts they took off your bike, H.D. shelved them to resale.

I book marked the web site. I have been buying some parts from J&P Cycles. Some of there stuff is good...but is after market.

[Bigincher]

I have been buying some parts from J&P Cycles. Some of there stuff is good...but is after market.

I really try not to badmouth anyone, but I will say that everything I've bought from J-P has been pure junk. I think they buy V-Twins rejects. There is ALWAYS a better choice than J-P. But I will say I have bought brand-name items there--- but in the case of brand-name items, it doesn't matter where you buy them, it's still the same part.

[George Greer]

I have been buying some parts from J&P Cycles. Some of there stuff is good...but is after market.

I really try not to badmouth anyone, but I will say that everything I've bought from J-P has been pure junk. I think they buy V-Twins rejects. There is ALWAYS a better choice than J-P. But I will say I have bought brand-name items there--- but in the case of brand-name items, it doesn't matter where you buy them, it's still the same part.

I agree about J&P, I won't buy anything from them. Junk and when you call to ask anything........you normally get a smartass on the phone.

If I am going to spend my money with you, I expect at least questions answered, and not by a asshole, that says "Anybody that can use a multimeter and read, should be able to rewire our prewired harness"...

Why in the hell should I have to rewire your product that you sold....should have been right in the first place.

Screw that and them.

Venting over.

George

[Bosheff]

Shitcan the cork seal. It doesn't do a thing in my opinion. If all else is right, you should not have a problem. As far as using silicone anywhere in the mixer, DON'T....bosheff

[amiabledave]

Bosheff, can you elaborate on the DON'T part? Could the curing process damage the inner parts?

[Bosheff]

Silicone was never designed to be used in an "oil bath" situation. The only place I use silicone is on exhaust pipes between the exhaust spigots and the exhaust pipes. People use that shit everywhere and it makes me sick when I gotta try to git it outta oil pump bodies and oil scavenger systems. If it is supposed to take a gasket, use a gasket, not silicone. Prep the gasket surfaces, and torgue to the proper spec. Anti-sieze makes an excellent gasket sealer if needed, and ya don't have to scrape the surfaces when taken apart. The people that came up with silicone should be shot then drawn and quartered....bosheff

[1950Panhead]

What is the part number of the seal in the photo?
Ray says these are 1977 parts.
Is the OD of the shaft and the ID of the gear the same for early panheads and can the seal be used?
The 41-54 parts catalog does not show a seal in the gear.
Jerry

[Cotten]

Jerry!

It looks like two 12013 seals crammed in where there should be one.
It was introduced in '65.

Please inspect the main drivegear's fit to the shaft before assembly!

Good luck,

....Cotten