Oil Blow By

C00lHandLuke

Active Member
I'm familiar with oil "blow by" and I have searched the boards for something applicable with no luck, so be patient if this has been addressed.

When I first purchased my 2003 Chopper, it had the stock Super G carb with the stock breather. From time to time after a ride I noticed a little bit of oil down the right side, not a lot but a little spray. After some research I learned that it was known as "blow by" and it was fairly common on most V-Twins. Although the oil was minor I wanted it corrected. After talking to a few people, and reading up on things, I decided I would get the S&S Tuned Induction breather with the mounting bracket that routes the oil back into the crankcase (I think). Well anyway ihad the S&S breather with the bracket. Believe or not I still have the Blow by, this time I can't really tell where it came from. As a matter of fact I think it's a little worse. The oil seems to be coming from under the chrome top ( rocker box I think is what it's called) and/or around where the top exhaust is mounted to the back side of the "V". Like I said, I really can't tell where it is coming from.

Is it possible that the re-routing of the drain is causing it to exit somewhere else? If so how in the hell do I correct it?

I would really appreciate any advice.
 

Dawgboy

Active Member
When engine cools down after a ride run your finger along the seam of the rocker box and the head. Check your finger every few inches. If it is coming from the rocker box you will see it.
 

C00lHandLuke

Active Member
I'll check it ASAP but I'm pretty sure that's where it is coming from. For one there is no oil on any visible part of the motor or breather, it accumulates right where the rear/top exhaust connects to the motor and the right side of the oil tank.

Last night after I clean the bike I noticed some oil under the rocker box facing the rear of the engine.

If it is coming from under the rocker box, what do I do from here??

Thanks.
 

Dawgboy

Active Member
Pull the box and replace the gasket. About $50 for a set of two as I recall. Need to pull the gas tank (on my mastiff anyway), and collapse the pushrods and readjustment afterwards. Threads on here describing that. Not too bad. May need to grind down an allen to get at the cover bolts.
 

BadBrad

2005 Pitbull
You really need to find the source of the leak or you may just be pissing in the wind and pissing away your money. From your description, I would check 2 main areas. Like already mentioned, the rocker box gasket is a common source for an oil leak. Also, if you're sure it's coming from the rear cylinder under the rocker box, take a close look at the upper side of the pushrods. The O-ring can eventually wear and allow oil to leak from either end of the pushrod. Clean the areas in question and take it for a short ride and determine the source. Both require the same basic procedure of collapsing the pushrods and removing the rocker box cover. Unless you find the source to be something different, you may as well replace both, the rocker box cover and base gasket along with the O-rings for the pushrods (both top and bottom O-rings).
 

C00lHandLuke

Active Member
Thanks, I will do. I cleaned it pretty good yesterday and I'll take it for a short trip to see what it's doing.

Again, thanks for the advice.
 

C00lHandLuke

Active Member
On the Chop you shouldn't have to remove the gas tank plenty of room to get a wrench in there
So your saying it should be enough room to get only Allen wrench and remove the bolts? Does that mean I also shouldn't have to remove anything else to get the rocker box off as well?
 

BadBrad

2005 Pitbull
I have the Pitbull and had to modify/cut down an allen wrench to get it to fit between the rocker box bolt and frame. The chopper should have more room. You should not have to remove the tank or anything else to remove the rocker boxes.
 

MyDogPete

Active Member
You really need to find the source of the leak or you may just be pissing in the wind and pissing away your money. From your description, I would check 2 main areas. Like already mentioned, the rocker box gasket is a common source for an oil leak. Also, if you're sure it's coming from the rear cylinder under the rocker box, take a close look at the upper side of the pushrods. The O-ring can eventually wear and allow oil to leak from either end of the pushrod. Clean the areas in question and take it for a short ride and determine the source. Both require the same basic procedure of collapsing the pushrods and removing the rocker box cover. Unless you find the source to be something different, you may as well replace both, the rocker box cover and base gasket along with the O-rings for the pushrods (both top and bottom O-rings).
This was my issue. Replaced both last year with new gaskets and O-rings and no ploblems since. Mine was pretty straight forward when I looked at it that it was not puking.
 
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