Cause besides Blown Head Gasket?

[darkbane]

I just went on a ride this afternoon on my '83 GS650G cafe and after about ten or 15 miles I pulled over and noticed an oil leak on my top end on both sides.

I wasn't driving extra hard or anything, just typical city driving on a 60 degree day. I don't know how long it's been leaking, but it looks very fresh, and I've never had a leak on this bike. I am the second owner and it doesn't even have 5000 miles on it yet. I didn't notice any performance or idling problems while driving today.

*First Question: Could anything cause this leak besides a Blown head gasket?

*Second Question: I've been running my bike with a 4 into 1 head with no muffler, so I haven't really had any back pressure while driving for the last two months. Could the lack of back pressure cause a leak like this?

*Third Question: If this was a blown head gasket, would it leak in the exact same spot on bath sides of the engine. I'm just noticing the leak on the two outside cylinders, but nothing noticeable on the two inside cylinders.

*Forth Question: If I do need to replace the head gasket, how much does a shop normally charge for this type of project?

I plan on cleaning this all up and driving her normal and seeing if it continues. I'd appreciate any feedback or suggestions you all might have for me. Thanks.

You can check out a few more pictures of the leak here:
http://www.cgshane.com/GSLeak.htm

 

[tkent02]

find the leak... clean it and run it a little bit, find out exactly where it is coming from.
Some people like to powder it up as an aid to pinpointing the source...
It's all do it yourself stuff to fix it, not too hard.

 

[ironb12s]

Yeah, and it wouldn't hurt to put a torque wrench to all of the head bolts while you're at it. Check compression when you have time.

 

[Big T]

1. Blown head gasket
2. Probably not, but give your valves a break and get some muffler packing. Your bike will run better and every one you go by won't hate you
3. Yes
4. A lot of $$ if you can find someone to work on something that old.

Get a torque wrench, and loosen up all 10 bolts a bit and retorque them. That may do the trick.
If not, you're probably looking at $150 if you do it yourself. Gaskets, valve seals, valve adjustment, maybe camchain sliders.

 

[Guest]

I'd loosen and retourque the head. Follow the tourque sequence and use a tourque wrench. I think it's about 30 lbs except for the small bolts which are 10lbs if I remember correctly.
Also make sure the breather on top of the head is clear.

 

[nabrams]

If your engine is running very hot (indicated by white plugs) that could have led to burning up the gasket enough to cause the leak. Sooner or later (maybe hundreds of miles later) you'll lose enough compression that the bike will be nearly impossible to start.
Go ahead, ask me how I know.

Now this is not meant to discourage you, but you should know what you're getting yourself into.
Replacing a head gasket is not going to be simple for someone who's never done anything more complicated than changing the oil, brakes and the like (if that's the level you're at). Not that you shouldn't attempt it - just that you should expect it to take MANY hours, and make many mistakes before getting it right (and probably have to buy a whole slew of new tools - quality torue wrench, valve depressor tool, etc.). You will almost certainly snap one/several exhaust bolts or camp cap bolts (which may require drill/tap/heli-coil), the cam chain needs to be set right on the cam shafts, the surfaces must be spotless and NOT warped in order for the gasket to seal properly, etc.
I did it, and I'm glad I did (saved a ton of $$$), but it was much more time consuming than I thought it would be (shearing a couple of bolts added tons of time to the effort - had to CAREFULLY drill the bolts out).
In short, if you've got the time and patience, go for it. The tool acquistion costs and the the cost of the gasket are miniscule compared to what you'll pay a "shop" to do the job. And the "shop" will likely make you wait for weeks/months till they get around to your low-profit job.

 

[trippivot]

there is a rubber "O"ring that has gotten flat from age and heating and cooling cycles. the aluminum of our engines has a large expansion and contraction factor.the rubber keeps a great seal for years but after years worth of time the rubber gets tired and just stays flattened. just a little seepage is what you are seeing that has slipped past the sealing barrier. depending on how much you want a perfect seal there depends on what you do. it is harmless at this stage.There is no compression leakage as the term "blown head gasket" implies.

to remedy this type of simple oil leak you will have to replace the o rings and head gasket, because the head gasket has a 1 time metal crush seal around the cylinders that should not be reused/retorqued.

re torquing all the head bolts wont bring life back to the tired rubber sealing "o" ring.

the problem is not severe. it wont hurt the engine, just make it dirty. it is annoying and unsightly. but I'd clean the engine more often and not worry about it . take care of it when there is a real need to remove the head.

If you do think this is a real need to remove the head
and you cannot live with just a little bit of seepage = NOW is the time for a valve job, new valve guide seals, possibly valve guides, maybe valve springs, and a complete carbon build up removal of all inner surface areas. inspect all inner moving parts and get everything done in there while you have the head off of the engine. Do it once, not twice or three times. unless you want to do these important things at a later date when you will be buying the same o rings and head gasket all over again. and again.

 

[ironb12s]

I would follow the first reply, and clean it up to see where the oil is REALLY coming from. It may be seepage at the O ring, or it could be loose bolts at the valve cover.

The torque values seemed low to me for the head bolts, until I looked at the specs for my Bandit. None are higher than 28ft/lb around the head, and the valve cover is less than half that. I'm used to the specs for automotive engines, I guess... :?

 

[ironb12s]

Now this is not meant to discourage you, but you should know what you're getting yourself into.
Replacing a head gasket is not going to be simple for someone who's never done anything more complicated than changing the oil, brakes and the like (if that's the level you're at). Not that you shouldn't attempt it - just that you should expect it to take MANY hours, and make many mistakes before getting it right (and probably have to buy a whole slew of new tools - quality torue wrench, valve depressor tool, etc.). You will almost certainly snap one/several exhaust bolts or camp cap bolts (which may require drill/tap/heli-coil), the cam chain needs to be set right on the cam shafts, the surfaces must be spotless and NOT warped in order for the gasket to seal properly, etc.
I did it, and I'm glad I did (saved a ton of $$$), but it was much more time consuming than I thought it would be (shearing a couple of bolts added tons of time to the effort - had to CAREFULLY drill the bolts out).
In short, if you've got the time and patience, go for it. The tool acquistion costs and the the cost of the gasket are miniscule compared to what you'll pay a "shop" to do the job. And the "shop" will likely make you wait for weeks/months till they get around to your low-profit job.

Sage advice. Changing the head gasket is easy if you take your time, and have this forum to call on for help. Copious use of penetrating oil at the rusted fasteners will prevent sheering off, as long as you don't force the issue. Soak the parts that you are having trouble getting loose repeatedly and often. Heat may be applied with MAPP cylinders, just keep the extinguisher handy. And, you will learn so much more about the bike if you do it yourself. Shops don't wanna mess with things pre-1990 anymore, unless it's something simple, or you bring them a simple problem to fix.