Oil Leak engine sprocket

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Oil Leak engine sprocket


Post by txpan49 »

I just had my 49 totally rebuilt and got to put the first 10 miles on it. When I got back to the house there was oil dripping pretty steadily from the front of the primary area under the main shaft. I pulled the primary belt and inner primary to get a look at the seal. It is brand new but I did notice oil wetness around the outer edge of the seal where it seats in the left engine case. I called the mechanic that did the work and he mentioned that some seals are different size and the one he put in he felt was not as tight as he would have wanted. Honesty at least. I believe some oil is supposed to get through right? Is there anyway to seal this better? I am thinking about ordering another seal.

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Re: Oil Leak engine sprocket


Post by Cotten »

Before you throw blame or money anywhere, drain the tranny and fill it with mineral spirits or kerosene. Then you can observe exactly where the leakage occurs.
This may make life easier with your mechanic, as well as saving you money in the long run.


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Re: Oil Leak engine sprocket


Post by mbskeam »

is this a oem style or the colony with the seal in it?

on mine I put silicone on the outside edge into the area that has the snap ring, this has stoped any weeps that might find there way out. I just cleaned it real good with lacquer thiner and Q-tips until they stayed white then put a bead into the groove, let it sit over night and put it back together,
you might try this, it cant hurt.
but if you let oil leaks drive you nuts you will end up like me.........
I feel much better now....


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Re: Oil Leak engine sprocket


Post by txpan49 »

Cotton, I am sorry I am not very descriptive in my post but I meant the engine shaft. And sorry about the honesty comment, he is a darn good mechanic. My comment was that he told me immediately and helped me narrow down the symptoms.

Mbskeam, thanks I was going to ask about putting some sealer on there. I am not sure if it is a Colony but yes it has the seal and retainer ring. I am thinking about ordering a new one from JP to see if there might be an O.D. difference. The oil seams to be coming from the outer most edge where I believe it is metal to metal fitment.
I have not checked the oil pressure. I am wondering if perhaps it could be too high. Do you think that could cause an steady leak? I am not concerned about a small leak but the steady drip has me concerned.

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Re: Oil Leak engine sprocket


Post by fourthgear »

You might want to make sure you breather is venting correctly , you did mention you had a belt drive , some people plug it up or inadvertently cause a restriction and that can cause all kinds of problems with oil blow by.

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Re: Oil Leak engine sprocket


Post by Raggs60 »

I have a 48 pan and I put a tech cycle belt starter kit 5 years ago and always had that %$#@*&^ oil leak, had to change belt, it got so soaked with oil
and got into clutch plates, So i put stock slinger back in, it has a reversed thread to keep oil in the engine and supports shaft,
I took a 65 distributor cap cut it down to a little under 1/2" bolted it to sprocket pulley and it acts as a oil catcher just as a precaution, works on my bike
changed my clutch plates to wet/dry, so if it gets oil on em they wont cause creeping, I buy extra belts on ebay 50 bucks, keep 1 in saddlebags every trip, you just dont no when its gonna snap. safe ridin

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Re: Oil Leak engine sprocket


Post by kitabel »

Open the sludge trap. Does more than an ounce or two oil come out? Your oil return to the tank is not keeping up with delivery to the cases.

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Re: Oil Leak engine sprocket


Post by RooDog »

Also, don't overfill the oil tank. Only check the oil level after the engine has run a few minutes to scavenge all the oil it can from the bottom end, and then check your dip stick, and follow the guide marking on it. Too much oil can cause blow by and puking/oil bypassing the crank seal, or whatever you have there behind the motor sprocket/pulley.....

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