air box dripping oil

[Dogma]

Yes, another one, but this time it's different, I promise. I searched the forums, and I can only find one thread on this symptom that didn't wind up being a bad petcock / stuck needle valve resulting in a crankcase full of gas.

Mine is consuming oil, not overflowing. Last weekend I did about 500 miles on the slab, and used a quart of oil keeping a correct level in the sight glass. It's leaving puddles, the bottom of the air box (and the top of the top case) is wet with clean-looking oil, and the source of the puddles seems to be the air box drain tube. Not the secondary drive, Josh. I cleaned that, and it stayed clean. Gear oil level is good.

The one thread I found that didn't end with a crankcase full of gas was never really resolved. Someone mentioned a compression test to check if blow by was pressurizing the crankcase and blowing oil out that way. I've been meaning to get a compression tester anyhow. I'll try to get that done tomorrow.

It dripped occasionally last year, but seems to be worse this year, and getting worse still. I used maybe a quart during all the trips to BC this year, and I'm sure that totaled more than 500 miles. Granted, not all turning a constant 5700 rpm.

So, is this likely something I need to deal with before WV, or can I maybe wait until this season is over (assuming oil usage doesn't get worse). What sort of new mechanic adventure am I in for? Or do I need to post compression numbers before I can get answers to that?

[almarconi]

First thought that comes to mind is that there is too much oil in the engine. Oil coming out of the breather hose into the airbox.

Second would be piston blowby like from a stuck or broken ring or damaged piston. Start by checking compression.

Pull the hose of the airbox and put your finger over it and see if you feel pressure with the engine running.

Thats about all I can think of at the moment.

[SqDancerLynn1]

Pull the breather cover off the valve cover, check to make sure the metal mesh filters are in place. Run the hose into a soda can, catch can and see how much oil blows out. If you still get alot probably time for rings ? 500 miles to qt is not good, could be worst.. as long as it doesn't foul the plugs , create a smoke screen

[TheCafeKid]

Like suggested I would pull the breather cover and check that the mesh is still intact. How long are you waiting before you add oil when looking thru the site glass?? It takes a few minutes or more for the oil level to stabilize after shutting the motor off. If you're not waiting that long, and its getting full that fast, you may in fact have it overfull. Again, as i have said many times, if you over fill one of these motors, it wont be long untill it shows you where your weak gaskets are. Remember that day we went riding and my cam chain tensioner gasket was leaking everywhere? I had it overfull. Mainly because i wasnt sure yet how much to fill it with the new cooler id installed, but none the less it was over full. Its not uncommon for your blowbly to blow oil vapor out however, especially when temps in the motor as well as ambient are high. I run a hose and a filter on the end of it, back to where the airbox on my ES should be, no catch can, and yes, there is some film back there from time to time. When is the last time you've pulled your airbox and cleaned it? It could be build up over time that youre seeing as well. How much oil is it using over 1000 miles? These motors WILL use oil, no matter how tight they are. My 1100G, tip top shape, would still use bout a 1/4 qt or so every 1000 miles. Of course, if you change your oil as often as is suggested, you probably dont notice it. I know you tend to run your oil a little long in the tooth. Thats another thing, if you run the oil for 3, 4k miles or so, its going to thin out from break down, and this might increase the chances of it coming thru the blow by.

[Dogma]

Well, when I checked the oil yesterday (beautiful day to ride, btw. Checked out the Stone Lick area), it had been sitting for the whole week since I got back from Cleveland. So it had time to settle. And the oil is fresh this spring, so it should be in good shape on that count. Since it's was right on the L in the sight glass (yeah, on the center stand), it doesn't seem like being overfull is an issue.

The mesh in the breather seemed to be in good shape when I adjusted the valves this spring. It's possible I mashed them when I put it back together, so I'll check that too. Glad I put on Real Gaskets this year.

Well, I'm off to get a compression tester. I'll pick up some longer hose to rig a catch can while I'm there. Then I'll pound a can of MD and remember not to smash it so I can use the can.

Thanks for the input so far. I'll report back in a bit.

P.S. Empty can + rubber mallet = therapy

[TheCafeKid]

Well, when I checked the oil yesterday (beautiful day to ride, btw. Checked out the Stone Lick area), it had been sitting for the whole week since I got back from Cleveland. So it had time to settle. And the oil is fresh this spring, so it should be in good shape on that count. Since it's was right on the L in the sight glass (yeah, on the center stand), it doesn't seem like being overfull is an issue.

The mesh in the breather seemed to be in good shape when I adjusted the valves this spring. It's possible I mashed them when I put it back together, so I'll check that too. Glad I put on Real Gaskets this year.

Well, I'm off to get a compression tester. I'll pick up some longer hose to rig a catch can while I'm there. Then I'll pound a can of MD and remember not to smash it so I can use the can.

Thanks for the input so far. I'll report back in a bit.

P.S. Empty can + rubber mallet = therapy

Ive never once seen that bike smoke Dale, so dont jump off the deep end yet. You checked UNDER the bike?? Slow leaks there can sometimes never spot your drive but still leak enough over time to show that much loss. Fresh this spring eh?? how many miles?? Air cooled motors need to be changed WAY more frequently than you might think. And, if you find it DOES need a rebuild, dont fret. Get the parts, get the bike up here, we can have it done in one LONG day.

[Dogma]

Josh, Thanks for the offer. Get a load of this:

I swing by HF, pick up a compression tester and start testing. I hear a pop, and then a squeak with every compression stroke that sounds like I'm beating a squirrel with a mallet. I fool around a bit more, then discover that the o-ring on the adapter end is blowing out. It's not captured, so there's nothing but the o-ring's elasticity holding it against the pressure. Dain brammaged. Took that back to HF, and sure enough, the others they have use a similar o-ring design. ?!!?!

So I swing by Autozone and pick up one of their loaners. the o-ring that would seat against the head is just plain missing, but the same basic design. OK, I was going to try a metal to metal seal anyhow. I got 130 115 120 130. Then I realized that I was only hand-tightening the adapter against the head, and I may not have a good seal. So, I go back to #1, and just snug it with the wrench, like I'd tdo with a spark plug. I got about 135 on it. OK, move on to the others.

Not so fast. The adapter is stuck in the head, and won't turn out. Like a burr got pulled into the threads. I'm thinking now that the cooling engine clamped onto it. Anyhow, I can work it back and forth, so I keep trying. You guessed it, I broke the adapter off in the head.

Not feeling level-headed right now. There's an exhaust stud that's been broken off since I've ad the bike. I'm thinking, pull the head and get all these thread disasters sorted out, inspect the rings and bores, do the valve gudes... Someone talk sense to me, and please pardon the mixed verb tenses.

[TheCafeKid]

well youre likely going to have to pull the head because the chances of you getting that gauge end out of the head without f-ing the threads up are pretty slim... If you want, seriously bro, order your top end kit (they sell a top end kit, its about 50 bucks cheaper than the complete gasket kit, and it includes every seal, gasket, washer etc you need to refurbish the top end, minus rings) Bring the bike up, we'll take it down, disassemble the head, you can take it to a machine shop (Steve knows of one around here that did some decent work) and get the head cleaned up, the studs removed, the deck planed, etc etc and by the time you get that back your kit should be here. It will take us one solid day of work, and we can have it tip top. If you want to spend the extra cash, while we're in there you COULD go ahead and do the rings since something was apparently amiss... Actually, why dont you just give me a call man...LOL

937-672-7684....home all night, will be in the shop working on various things...

[Dogma]

Public thanks for the help Josh. Got my tracking number from Z1 already.

[TheCafeKid]

Thanks for the thanks man, and you're welcome... Suddenly ive become the neighbourhood GS guy apparently. I had a guy at work's mom call me with an 85 550L that needs a new R/R and fork seals and a valve adjustment. Said the shop charged her $75 to change the fork oil, but didnt change the seal. 75 bucks! to put fork oil in a fork thats leaking! they wanted over $200 for a R/R and to install it. I told her I would do the fork seals, the R/R AND a valve adjustment for 200 plus parts, which are going to amount to about 60ish bucks...Freakin STEALerships...

[Dogma]

Careful, or you'll have a 2nd career on your hands!

[ryonker]

I wish I lived by Josh!

Rick

[bwringer]

Probably well after the fact, but is the breather tube on the airbox open? There have been reports of the metal breather tubes on earlier GS850s rusting closed, which causes the crankcase to pressurize and leak.

[ryonker]

Probably well after the fact, but is the breather tube on the airbox open? There have been reports of the metal breather tubes on earlier GS850s rusting closed, which causes the crankcase to pressurize and leak.

Good point. I just restored the airbox on my 78 750. It looked pretty crappy so I decided to repaint it. I started cleaning some rust off of it and began cleaning the breather tube. It was pretty rusty inside. I scraped, blew it out with an air hose, scraped and more and more CHUNKS of rust blew out. I took a long piece of wire and scraped at the inlets inside the airbox. It took a while to totally clear that thing out.

Rick

[Dogma]

Probably well after the fact, but is the breather tube on the airbox open? There have been reports of the metal breather tubes on earlier GS850s rusting closed, which causes the crankcase to pressurize and leak.

Um, it was open when I cleaned it up early this spring.