Is there any reason the carbs would be leaking oil?

[freki]

My 1980 GS850L looks like the carbs are leaking a little oil after it runs for about +5 min. I notice the oil collecting on the bolts on the underneath side of each carb body.

[Zooks]

Sounds more like dirty fuel to me.

[freki]

It's actually new gas. It's the consistency of like a 5w-30 oil

[doctorgonzo]

Oil winds up weird places. Probably coming from the engine and collecting there.

[jadesystem]

Never heard of carbs leaking oil !! Maybe it is a defective PCV allowing some engine oil/oil fumes to migrate back into the airbox and eventually
to the carbs. This is just a guess. Never heard any oil in the vicinity
of a subsystem (carbs) where only gas should be present. And you
mentioned dripping oil fom the bowls.

Mmmmmmm. If it was dirty gas, you would know this immediately by
the density of gas versus the viscosity of the oil. And the discoloration
and microcontaminates in the gas.

This is a very good problem, and is quite perplexing. I'll get back with you on this friend !!

:-D\\/

[jadesystem]

Maybe you have an oil leak somewhere else, and it is splashing onto the exterior body of the carbs. If this is internal, and it is leaking out from
within the carbs, then engine oil must be migrating somewhere to the carbs.

Is the oil mixing with the gas fouling your plugs, and burning oil ?? Does
it run like crap ??

Let me know friend.

:-D\\/

[freki]

Actually yes it is running like crap right now

[freki]

Another thing that really confuses me about this is that the oil looks like it's dripping out of the bolts on the underneath side of the bowls.

[jadesystem]

Please take close-up pics for us. I want to see this. Very interesting
where gas is mixing with the oil. Never seen this !!

Thanks friend.

:-D\\/

[freki]

Okay, I'll get some pics of it later today

[mortation]

Sounds odd to me. Clean the whole engine with heavy duty degrease so you can see no oil. Then run the bike and watch the following:

Check your breather hose to be sure its not leaking.
Check your Auto Tensioner and make sure its not leaking
Check your oil pressure switch and make sure its not leaking
Check your Head/Base gasket and make sure they are not leaking

Did you check the compression of your cylinders? Maybe oil is leaking in around the pistons?? But you would have some pretty crappy performance from the bike....

[billstearns]

check camshaft cover gasket.

If oil from the engine is getting inside the carbs and then getting to the outside of the carbs would require some serious leaking of seals and gaskets i doubt that is the cause. It is probably spraying onto the carbs and running down to the lowest point where it drips off. I have blown the camshaft cover gasket twice in ten years and it blew two more times before i had it, i would look in that area. Or the crankcase vent tube has blown off the engine or airbox right over the carbs.

[Carter Turk]

The air box could be filled with oil from the breather tube and sucking into the carb. This happened to me on my 80 1100ET. The ringland area on #2-3 piston caved in, filling my air box with more than a quart of oil.

Check inside the air box in front of the air filter for oil residue. Or like others said maybe its the breather tube dripping condensation and oil onto the carb.

[Roostabunny]

The experienced guys here are teaching me that it's better to eliminate a couple of simple problems (like the ones Mortation mentioned) first before trying to solve an interesting (but unconfirmed) mystery that involves rebuilding the carbs or removing the head.

In other words
1.) Maybe it's your carbs, but probably not.
2.) There's plenty of simpler reasons the bike could be running crappy aside from ring failure or similar.

Oil leaks are sneaky. I was sure I had oil coming out of my exhaust header one point (which is about as likely as dripping oil from your carbs) and it turned out to be a cam cover gasket failure dripping down by my #3 sparkplug, through a hole between the fins and out the front of the block - right behind the exhaust flange. If you see a drip 5 minutes after startup, that's probably how long it's taking for the oil to flow from wherever it's leaking to your carbs and start to collect.

My suggestion would be to clean the heck out of the engine, start it up, and then watch like a hawk while shining a bright light in there. I get fast cleaning results with spray degreaser and the self-serve carwash (just let the engine cool for a while before degreasing and watch where you direct high-pressure water). Then I use spray foot powder (another GSR's idea) on the dry engine to make it more obvious where the oil's coming from. Others use talc.

Last time, I just plunked right down at the car wash after cleaning and watched the engine. Found the leak in about 2 minutes then rode home and fixed it in 20 (it was just a shifted cam cover gasket).

Any luck on pics of the problem, by the way? I'm really curious.

[Dogma]

I get fast cleaning results with spray degreaser and the self-serve carwash (just let the engine cool for a while before degreasing and watch where you direct high-pressure water)..

Good advice overall. Can you explain which areas to avoid with the high-pressure wash? Are there sensitive area on say, the carbs?