Board index Flathead Power-Technical Questions, Answers, and Suggestions Knuckles My EL sure likes her trans oil

My EL sure likes her trans oil

Moderators: Curt!, Pa

Post Sun Jan 04, 2009 7:58 am

Posts: 6
Hi All,

My 36 is dipping trans oil from the hole of the kicker arm behind the spring (gets worse when its running). Is there an upgraded oil seal?

Also its dipping from somewhere underneath and i cannot see where from.

Any similar problems/solutions?

Thanks

Jack

Post Tue Jan 06, 2009 7:56 pm

Posts: 646
Location: Detroit
I can't speak directly to a 36 because I have not owned one but generally there are a couple of bushings for the kicker "axle" shaft and a seal between them. Is there an "upgraded" seal? I don't know that either but there is always a "new" seal which normally does the trick for me. There are also "new" bushings.

As for the other problem, since you don't know where the leak is, it is going to be a little tough for someone to tell you how and what to fix. Why don't you remove the trans from the bike, wash it off in solvent, fill it with oil to the proper level (just below the fill hole), sit it level on some newspaper on a bench, go away for a few days, come back, and then try to see what if anything happened in the meantime.

It can leak from the main drive gear bushing, the main shaft bushing, a cracked case or kicker cover, an over-filled trans, any one or more of the 4 mounting studs, the bolt under the right side bottom area near the kicker, a bad kicker cover gasket, a bad lid gasket, or a worn out filler hole/plug. Maybe you have a pin hole leak in your oil tank with just enough leakage that you cannot readily spot from the oil tank, which makes you think it must be a trans leak. You get the point.
New Knuckleheads? Thank, you, Jesus!!

Post Tue Jan 06, 2009 10:17 pm

Posts: 122
Location: Mpls. area
Maybe if you push the bushings together a bit the rubber seal in between will expand and stop the leak, might as well replace it anyway if you go that far...Mike

Post Tue Jan 06, 2009 10:56 pm

Posts: 2687
Location: Los Angeles, CA
The 1936 EL had a one piece bushing. NO "O" RING. Just a cork seal behind the starter crank and spring. Knock out the single piece bushing and install the later two piece bushing with the "O" ring between them.

Post Wed Jan 07, 2009 3:31 pm

Posts: 6
Thanks a lot guys!!

Does the grade of the transmission play a role in dipping?

For example will a 85-140 dip less than SAE 50?

Thanks again

Post Wed Jan 07, 2009 5:12 pm

Posts: 646
Location: Detroit
Not in my experience. I do not run multi grade oils. I do use the same grade oil in the trans and engine.

Post Wed Jan 07, 2009 6:33 pm

Posts: 24
Location: My-am-mah, Flor-a-duh
I use straight 60wt in my four speed trannies; however, I’ve read on other tech forums guys running 75/90 multi-grade gear oil. Some run straight grade (50 or 60) with 25% of an oil additive called Lucus Oil Stabilizer, and there are others that swear by Lucus 85-140 gear oil.
Steven

1946 knucklehead
1976 shovelhead
2006 road king

Youth and enthusiasm is no match for age and treachery.

Post Thu Jan 08, 2009 2:37 pm

Posts: 6
Hello,

I have read that (depending on ambient temperature) SAE 50 or 60 should be used in the engine and transmission but you could use a multi-grade oil in the transmission only (preferrably 85-140).

Probably variant viscosity properties according to temperature aid the transmission as it tends to "heat up" more.

Post Sat Jan 10, 2009 11:20 am

Posts: 2399
Location: atascadero cal usa
they have found in the auto industry that thinner oil acually cools quiker then thick oil in a trans
and have used fish oil in the past but now use automatic trans fluid nowadays in std transmissions
the thicker oil is needed to help with leakage but doesnt stay as cool as the thinner oils
i suspect the issue you have is with worn bushings and no seal on that shaft

Post Sat Jan 10, 2009 5:45 pm

Posts: 65
Location: Aberdeen, SD

We use a split bushing machined to the proper length with a the square o-ring and replace the cork washer with a seal on 36EL kick covers. It makes a permanent leak free fix.
Carl and Matt

Post Tue Jan 20, 2009 5:03 pm

Posts: 24
Location: My-am-mah, Flor-a-duh
100incscoot wrote:
they have found in the auto industry that thinner oil acually cools quiker then thick oil in a trans
and have used fish oil in the past but now use automatic trans fluid nowadays in std transmissions
the thicker oil is needed to help with leakage but doesnt stay as cool as the thinner oils
i suspect the issue you have is with worn bushings and no seal on that shaft



100incscoot:

From the quote above it appears that you are recommending the use of ATF in a four speed tranny; am I reading this correctly?
Steven

1946 knucklehead
1976 shovelhead
2006 road king

Youth and enthusiasm is no match for age and treachery.

Post Sun Feb 08, 2009 7:04 am

Posts: 2399
Location: atascadero cal usa
sorry i'm a bit late getting back here
no i'm not reccomending the use of atf
i was telling that example to show that R&D work tells us thinner oil stays cooler longer or cools easier then thick oil does
for your application run what ever you use in the motor rather then automotive gear oil
its the happy medium between thick oil that does not dissipate heat well and thin atf that will leak from everywhere


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