Question for you S&S owners...

HOG

Member
I'm almost finished with my chopper build. I got it on the road this past Saturday. It has a 92" classic round S&S engine...very similar in appearance to the 117ci offered by S&S (the destroked model).

After a five mile ride I noticed oil seeping from the head gasket area on both cylinders at the exhaust port location.

I got this engine new and did the heat cycles as per the manual. Only seems to leak when I ride it?

Any of you folks have similar problems with your S&S? If so what was the fix?
 

bdmridgeback

Low Down Chop Shop
I would assume that it is actually the rocker boxes leaking just above the exhaust ports. I haven't heard of hardly any oil leaks on the S&S engines, at least in the Big Dog's. Exhaust gasket leaks, yes, but oil leaks, no.

I'd call S&S for sure and ask the source.
 

LDO

The Cleaner
Troop Supporter
If it's actually leaking from your rocker box, then yes. Happened to me but only after about 15k miles on my S&S 107.

Real pain in the ass.

Come to find out my lower rocker box gasket (blue 2-piece S&S type) was torn in several places.

Replaced those with the Cometic one piece and have put several hundred miles on the bike and no more leak!:)

Makes a man all happy inside!:D
 

HOG

Member
Any cahnce of a crank case or head vent blocked off?
Doesn't appear to be blocked off but we're gonna check that this weekend.

I would assume that it is actually the rocker boxes leaking just above the exhaust ports
Rocker boxes are tight.

Replaced those with the Cometic
Cometic's are my favorite, never had a problem with them on my other builds
 

V

Guru
The standar EVO or Super Sidewinder has breathers that are thru the air cleaner backer plate bolts at the top of each head toward the carb.
 

HOG

Member
The standar EVO or Super Sidewinder has breathers that are thru the air cleaner backer plate bolts at the top of each head toward the carb
You are correct on standard EVO "V". My S&S V92 does not have the banjo breather bolts at the carb plate; it has plumbing that is internal to the head that is ducted to the carb
 

HOG

Member
Old ass thread resurrected... V got it right! I had this problem from the beginning in 2009. Was doing some maintenance this past weekend and found the one-way check valve in the rear head was installed backwards from the factory....finally running oil free after all these years ;)
 
Last edited:

JoeFin

New Member
Guys I've been fighting an oil leak in my rear Rocker Box cover for a while now. I just can't seem to get it to stop.

I went through the engine when I started to get oil weeping from under the barrels. Replaced all the gaskets and put the engine back together no problem. But I did reuse the existing rocker box gaskets as they didn't come with the set of engine gaskets I got from TP Engineering.

Fired up first try and it looked good. Ran a couple thermal cycles before taking her out without any issues. Once I went out and got on it the oil started leaking pretty badly.

Got a new set of Rocker Box Gaskets from S&S and very carefully went through the rocket box assembly taking my time torquing everything gradually with a new digital torque wrench. Same thing, ran 2 thermal cycles with no issues but once I went out and strarted twisting it the rear rocker box just above the exhaust started leaking

What am I missing
 

john sachs

Well-Known Member
Clean the area.
Remove the timing hole plug. Use low air pressure, with a rag wrapped around the air gun at the timing hole.
Mark the area of the leak on rocker box, etc.
Remove part, or parts.
Check for flatness/warpage.
Also, when a valve guide, or valve seal go bad, oil may come out of the exhaust port, and dispersed by exhaust pressure, sometimes looking like a rocker box leak. :oldbang:
John
 

Mickmorris

Well-Known Member
Supporting Member
Guys I've been fighting an oil leak in my rear Rocker Box cover for a while now. I just can't seem to get it to stop.

I went through the engine when I started to get oil weeping from under the barrels. Replaced all the gaskets and put the engine back together no problem. But I did reuse the existing rocker box gaskets as they didn't come with the set of engine gaskets I got from TP Engineering.

Fired up first try and it looked good. Ran a couple thermal cycles before taking her out without any issues. Once I went out and got on it the oil started leaking pretty badly.

Got a new set of Rocker Box Gaskets from S&S and very carefully went through the rocket box assembly taking my time torquing everything gradually with a new digital torque wrench. Same thing, ran 2 thermal cycles with no issues but once I went out and strarted twisting it the rear rocker box just above the exhaust started leaking

What am I missing
I must be missing something. You have TP or S&S engine?
 

JoeFin

New Member
The set Ray sent me did not include the Rocker Box Gaskets. Those I used the S&S Rocker Box Gaskets.
.
I might be assuming too much here but I thought TP Engineering used S&S Heads and recut the ports with a CNC using their proprietary porting profile.

I had the HD Evo gaskets around the shop, and through a case of mistaken identity tried the Larger S&S Rocker Box Gaskets. The only Gaskets that lined up correctly were the smaller S&S Rocker Box gaskets. And yes it has new gaskets through out
 

Mickmorris

Well-Known Member
Supporting Member
The set Ray sent me did not include the Rocker Box Gaskets. Those I used the S&S Rocker Box Gaskets.
.
I might be assuming too much here but I thought TP Engineering used S&S Heads and recut the ports with a CNC using their proprietary porting profile.

I had the HD Evo gaskets around the shop, and through a case of mistaken identity tried the Larger S&S Rocker Box Gaskets. The only Gaskets that lined up correctly were the smaller S&S Rocker Box gaskets. And yes it has new gaskets through out
Interesting. I believe TP makes all the components of their engines in house. So you definitely want to do what John has suggested. You should be able to locate the source by following his instructions. Keep us posted.
 
Last edited:

JoeFin

New Member
Interesting. I believe TP makes all the components of their engines in house. So you definitely want to do what John has suggested. You should be able to locate the source by following his instructions. Keep us posted.
It been quite a bit of information gathering, some from this forum to identify the engine.

The original owner passed away (non bike accident) and I purchased the bike from his son, who wasn't a rider with barely over 9K miles on it. From the engraving "Big Dog" on the side of the case as told to me here on this forum. it was a TP engine. While trying to identify these rocker boxes, I even called Tech Support at S&S Motors and ran the engine numbers by them. S&S Tech Support told me it was a TP Engine.

Which all that being said - these are not TP Engineering Rocker Boxes, (wish they were) they don't have TP's propietary "Pro-Vent" design incorporated into them.

So if I seem to talk out the side of my arse - please excuse me. It's a wonderful bike with incredibly quick responce. but this one leak has been a journey to solve.

Thank you all for your help
 

Mickmorris

Well-Known Member
Supporting Member
It been quite a bit of information gathering, some from this forum to identify the engine.

The original owner passed away (non bike accident) and I purchased the bike from his son, who wasn't a rider with barely over 9K miles on it. From the engraving "Big Dog" on the side of the case as told to me here on this forum. it was a TP engine. While trying to identify these rocker boxes, I even called Tech Support at S&S Motors and ran the engine numbers by them. S&S Tech Support told me it was a TP Engine.

Which all that being said - these are not TP Engineering Rocker Boxes, (wish they were) they don't have TP's propietary "Pro-Vent" design incorporated into them.

So if I seem to talk out the side of my arse - please excuse me. It's a wonderful bike with incredibly quick responce. but this one leak has been a journey to solve.

Thank you all for your help
We are all here to help and learn! If you could take a few pictures of the engine/ rocker boxes (each side) and perhaps the tops of the rocker covers might help us diagnose what is going on. If you can get a good picture of the area of the leak also that would be awesome. I have a TP 107 also so it’s all good information!
Mick
 
Last edited:
Top