Oil deflector transmission

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Oil deflector transmission


Post by Demoman » Wed Apr 09, 2008 2:36 pm

Post by Demoman on May 18, 2004, 2:10pm

I am taking apart my 64 FLH and on the transmission mainshaft the previous owner cut off the oil deflector. It looks like he could not get to the nut on the shaft and decided this was the way to reach it. I put a new one on and now the inner primary does not seem to fit right.
Do I need the oil deflector and if so does it fit behind the inner primary or inside the the inner primary hole when the primary is installed and the chain is adjusted?



Post by Plumber on May 18, 2004, 4:47pm

The deflector goes behind the big (neoprene sealed) main shaft nut. On top of the trans sprocket. It is a '39 part and was put there to keep oil leaking from a worn main shaft bushing, from draining on to clutch drive and fiber plates. Belt drives don't need the slinger, but do need an oil sealed "Duo-nut". Chain primarys need the slinger, in my opinion.
Demonman, why don't you register? We are trying to pump up the membership to break the 1000 mark. Thanx

Post by PanPal on May 18, 2004, 5:13pm

The deflector large end lip should be inside the cover. I'm not sure about a 64, but on a 59 the back two bolts holding your inner primary have springs and cotter pins on the bolts. If they are bolted directly to the mounting tabs, you will eventually crack these tabs on the inner cover. I have seen people run without the deflector. I would not recommend it. I think Plumber covered things pretty well.

Post by Cotten on May 19, 2004, 12:55am

Neoprene seal on a '64? On a nut?
That's modern aftermarket stuff: Beware that the "supernuts" often interfere with the clutch hub boss before '65, unless lathe-cut. If used on a '65 and later gear, the OEM seal should be removed.
The purpose of the deflector was to spin oil from the main drive gear back into the primary. If you run a '65 and later gear with a seal, it is unnecessary,, except if you ever might run in the rain.
If you must eliminate anything for clearance, eliminate the lock tab and use Loctite.

Post by Plumber on May 19, 2004, 1:55am

The lock tab....with the "hunter tang"? How are you tightening the hub nut. By hand? Not with a "butterfly" air tool. You could run the hub too far onto the mainshaft. The tang on the (three finger) lock tab registers in the hub keyway slot. Maybe some mechanics don't use it and maybe not the "L" piece either, that goes in any one of the the main drive gear channels registered in any single slot of the mainshaft spacer.... on Belt drives. But, I trust the hunter tang and 70 ft. lbs of torque when assembling the clutch hub to the mainshaft. Me only though.

Post by Weez on May 19, 2004, 2:58am

On a tin primary the oil deflector is a little larger than the hole in the primary, You don't have to take off the inner primary to change all this, So the question where does it go? it would go on the inside of the primary, and I'd run it, you might have a funky inner primary to have had to cut it off and it also not fitting right.

Post by Plumber on May 19, 2004, 3:01am

My opinion is that you need it unless you have a belt. Then you won't need it. The Duo-Nuts are different mfg. than the Super-Nuts.

Post by Mbskeam on May 19, 2004, 3:41am

hello,I had to shorten the slinger 1/8" as it hit the back side of my clutch hub. All is well now, as this was a problem on mine for years, and quite annoying as it would not always do the rub. Years ago I put on the supper nut, the one with the seal and O-ring on the inside .Red lock tight with no lock tab, To tighten up, out comes the impact gun ;D

Post by Weez on May 19, 2004, 4:31am

I agree with both of ya'll I had the noise problem and I also think you don't need it with a belt. But those super nuts or whatever that says it stops the leak don't work cause what I think gets messed up is the case where the oil seal goes, it must lose shape and oil leaks out no matter what. I put "red stuff" don't remember the name but some kinda of bearing seal and it did help a lot but it would still, eventually, leak out that area anyway. But I don't think I have ever heard of somebody shortening it. I'll put that in knowledge bank........thanks

Post by Plumber on May 19, 2004, 6:07am

How many ft. lbs. do you get out of that impact wrench. "Butterfly"impact wrench has the highest setting at "8", I think that is 45 ft. lbs. tightening and 70 ft. lbs when loosening. I have the specs on the butterfly out in the shop.

Post by Cotten on May 19, 2004, 11:56am

Oil leakage occasionally comes past the spacer drive key and gearsplines if the nut loosens, tranny is overfilled, sits for extended periods, etc., so a little sealer under the nut doesn't hurt if your particularly anal.
It was this oil that the outer o-ring on the Duo-Seal stupor nuts was intended to retain.
The only other place oil can seep is out of the end of the drive gear, which only had a "slinger" groove, or reverse thread cut into the bushing, to throw oil back into the tranny....until the '65 end seal was produced.
This is the oil that the deflector was intended to keep within the primary cover.
The stupor nuts have the end seal built in, but they were intended to replace the '65 seal, as they protrude into the gear. The original seal must be removed. They will not work with a pre-'65 gear at all, as there is no counterbore for it.
So basically, the sealed nuts are a late-model bandaid.

Post by Plumber on May 19, 2004, 1:20pm

You'll want a '65 main drive gear (all AM drive gears are recessed for the 12013A seal) to run a belt primary.

Post by Mbskeam on May 20, 2004, 4:57am

hello, what i forgot to say was that before i put on sprocket, i fill splines on tranny with rtv sealer then put on sprocket then a thin coat of sealer then the super nut that DOES work.my nut has o ring groove cut into face of nut and the outer seal that the main shaft goes thru. the andrews 4th gear also has the late model seal and this combo gives me leak free set up ,12000 miles and no problems. unless u count the time i filled it a wee bit to much. and they will leak for sure.

Post by 57stroker on May 21, 2004, 5:24am

Cotton is right about the back of the clutch basket hitting the nut. You can forget faceing it in a lathe unless you have about a $100 worth of carbides to throw at it. Mine was harder than the gates of hell. A grinder did it in a jiffy (ouch!) One has to wonder if the nut is actually stopping the oil or the sillycone the instructions have you put on it.

Post by Mbskeam on May 21, 2004, 6:17am

hello, my nut must be some odd ball one as it does not have this problem. I think it was made about 15 years ago. If I remember right it about 3/8 thick with a hole bored for a seal, and Oring on back . I have heard of what you guys are saying but have not seen it for my self . it must be a diff nut that i have than a super nut.and with a impact gun , butterfly etc. foget trying to get a tourqe reading as there are to many varables. as for my way some might not like it , but it works for me. ;D

Post by Cotten on May 21, 2004, 12:13pm


Perhaps you are running a '65 and later hub, which does not have the interfering boss.
It should be noted that passage of oil through the long main drive bushing is hindered by a lack of an outlet on the far end, when sealed.
The factory apparently felt that the added stability of of the primary support bearing in '65 over-rides the need for oil flow, and added the end seal.
Note also that the Factory always spec'd the same oil for the tranny as the motor. Use of thicker lubes hinder oil in this region, as well as the maindrive rollers that are only fed through the gear endplay, with no escape passage either.

Post by Mbskeam on May 22, 2004, 4:36am

hello, you could be right about my hub as it does not really have a boss that sticks out very far. It was a swap meet part from many years ago .In the land before E-bay. when parts flow freely around this part of the US, side note; at the last swap meet all the old parts 1970 and older would all fit in 1 booth space :'( :'(. And this is at our spring meet the big one in this area.

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