Oil in airbox 600ss - Ducati.ms

cjp377 · Nov 23rd, 2011, 4:15 pm

Can anyone tell me why I might have oil in my airbox?

Bought a 600ss that may have been raced so wonder if something has been done to the breather for racing. The expansion to airbox pipe has also been replaced.

Just about to start rebuilding the engine, as it's suffering from piston slap and I'd like to try and do something about it.

ChrisM · Nov 23rd, 2011, 4:29 pm

How did you diagnose 'piston slap'?

I doubt the bike was raced as they really wouldn't be competitive in any class.

Is it possible that the oil was just overfilled which got blew into your airbox and eventually was consumed by the motor creating a little excess smoke???

Chris.

470four · Nov 24th, 2011, 12:49 am

Excessively worn piston rings would cause blowback past the pistons pressurizing the crankcases blowing oil up through the breather?

VTGPDUC · Nov 24th, 2011, 5:57 am

See if there is gas in your oil. The carbs can become blocked by ethanol gum and allow gas into crankcase.

cjp377 · Nov 24th, 2011, 6:51 am

I've had the carbs off and given them a thorough clean, so worn rings is sounding like the cause as that would tie in with the piston slap too.

The engine is coming out for a rebuild, so can hopefully solve both problems at once.

ChrisM · Nov 24th, 2011, 7:21 am

How many miles are on the bike? When was the last oil change and how much oil was put back in.

I would eliminate the simple things first before you go through the time and expense of tearing the engine down.

What are the exact symptoms that you are experiencing? What tests have you already performed? The more details you provide, the better our collective diagnosis will be.

Chris

barnapkin · Nov 24th, 2011, 9:12 am

Previous owner did a lot of engine braking.

ChrisM · Nov 24th, 2011, 11:45 am

Sarcasm On:

It all makes sense now. There's oil in the airbox and the previous owner did alot of engine breaking. No need to do any other tests. It's obviously piston slap - you should immediately tear it down completely.

Sarcasm off.

If the rings are worn out, you can do a leakdown test. That should also tell you if the valves are not seating properly. I'm going to bet 10 internet dollars that neither of these are your issue.

You mentioned that the previous owner replaced the breather (or parts of it). The breather enables oil to get into the airbox. START THERE and make sure everything is working the way it should.

Or spend $2000 and 2 months to tear down a good engine and put 900SS pipes on it.

If you actually have a problem and are serious about finding a solution, please give us more details.

Chris

Kriis · Nov 24th, 2011, 1:19 pm

Quote:

Originally Posted by ChrisM

I doubt the bike was raced as they really wouldn't be competitive in any class.

wow, I don't post on here that often but just for starters :- DesmoDue (New Era MCC)

ChrisM · Nov 24th, 2011, 3:29 pm

You are right. The 600ss is a great racebike especially in a class that only allows 600ss.

Forget I said anything. I know not of what I speak. Good luck with the engine rebuild.

Chris