What happened? Blown head gasket?

[Fixxxer]

Hey guys, this is really depressing. I just got my GS550 a month ago and on Saturday I went for my first real ride that wasn't just down the highway with a friend of mine. We drove all around the Keweenaw peninsula of Upper Michigan (the "thumb" section if you're making a hand map). It was beautiful as many of the roads have a lot of twisties along Lake Superior with a gorgeous view and a refreshing breeze. Then today rolls around, and my bike craps out on me.

I was on my way home, about an hour drive, and had only gone about 30 miles. I was doing maybe 75 in fifth gear, not exactly beating the engine or anything, when all of a sudden I have no power, like I'm suddenly running on two cylinders. The bike kept running but there was next to no throttle response and I had to keep the rpms higher than normal to maintain speed. I went for a few more miles before it got much worse and I pulled over. There was smoke pouring from the exit valve (if that's what it's called) on the top of the head. I thought maybe it had overheated and if I waited a while it would be ok. So 15 minutes later I got back on and drove two more miles, but there was no improvement so I pulled over. This time I could see some oil leaking from the front of the head gasket. I waited almost an hour this time and then got on and started it up... it was hard to start and I had to keep giving it throttle to prevent it from stalling. I especially had to crank it when taking off in first gear to keep the engine running. It ran absolutely horribly and I could barely make it up hills... there was a trail of smoke behind me... I rode maybe five miles to the next gas station. When I got off and looked at the bike this time, everything was covered in oil. So much that I couldn't tell if it was coming just from the head gasket or from somewhere else as well. There was also oil in my right muffler pooled up that I could see. I bought a quart and had to put the whole thing in before the oil was back up to the appropriate level.

I then called a friend to come pick me up. He suggested that feeling like it was running on two cylinders and oil in the exhaust, as well as the leak I saw, was indicitive of a blown head gasket. Does this sound right? The bike is still at the gas station 20 miles away, and I'll have to go pick it up tomorrow evening after work. In the meantime, does anyone have any ideas as to what the hell happened? It had been running fine the day before and the whole ride today until this... it's really frustrating. I'm just hoping it's something I can fix without sinking too much money into it and get it back on the road. Thanks for the help.

[chef1366]

Check and see if there is fuel in the oil. You might of just filled up the crankcase with fuel and all hell broke loose. Could be as simple as a new petcock and a good carb cleaning.

Change the oil and do a compression test and this should tell you if the head gasket is blown.

[Fixxxer]

Thanks for the input, I'll check that once I get it back here. Another thing I remembered is that when I started it up again it made a sharp, quick hissing noise as though air was escaping in a short blast from somewhere... Anyone else have an opinion?

EDIT: Upon consulting my Clymer's manual, the thing that the smoke was pouring out of was the hole that the breather hose is supposed to be attached to (apparently the PO removed it) and the small leak was coming not from the head gasket but the front of the cam cover gasket...

[argonsagas]

Thanks for the input, I'll check that once I get it back here. Another thing I remembered is that when I started it up again it made a sharp, quick hissing noise as though air was escaping in a short blast from somewhere... Anyone else have an opinion?

EDIT: Upon consulting my Clymer's manual, the thing that the smoke was pouring out of was the hole that the breather hose is supposed to be attached to (apparently the PO removed it) and the small leak was coming not from the head gasket but the front of the cam cover gasket...

Pressurized air from combustion entering the crankcase would cause oil to blow out the vent, and the cause of that concern would be a head gasket. The hissing noise could come from that, but also could come from valves....back to the compression test. Smoke from inside the engine, and exiting the hose, could be either gasket or valves.

The suddenness of the problem suggests gasket. Either way, the head must come off.

Don't try to drive the bike. Pick it up on a truck and carry it home for repairs.

[nabrams]

Yes, typical blown head gasket symptoms. A compression test will tell the full story.
Happens to everyone eventually if you ride our old bikes long enough.
The good news: If I can do it, you can. When it happened to me I was pretty intimidated because I'd never removed the head off an engine. My Honda CB750 head can not be removed without removing the engine from the frame, so it was even more work (exhaust had to be re-mounted too!!!). I decided to take the plunge and do it myself. I researched here and in the manual thoroughly. I worked very slowly and carefully and triple-checked everything. Even so, I managed to snap a cam shaft cap bolt (it was really late at night and I started to lose my concentration - when you do, STOP and continue the work another day). I was able to carefully drill it out. I got the job done, including setting all valve clearances to spec. To my utter surprise, the bike started up the first time and ran well and still does today.

Bottom line - you WILL succeed, if you:
1. Do your research.
2. Work SLOWLY.
3. STOP working when you're tired, and continue another day.

[cvmgtwowheels]

That's the best advice I've herd in a while!! Go slow take your time.

[Fixxxer]

Well, I did a compression test... cylinder 2 was at 130, cylinder 4 was at 140, and cylinders 1 and 3 had nothing... needle didn't budge. Also, the 1 and 3 plugs were wet while the other two were dry. I poured some oil in and there was no change... according to the clymer's manual this means it needs a valve adjustment... does that sound right? Would a valve problem produce these symptoms in such a sudden manner? If so, is a valve adjustment what I should try first?

Thanks for the help.

[Nessism]

Skip the valve adjust, you blew the head gasket - combustion pressure is escaping through the gasket. Sorry for the bad news but there is no easy way out.

[Suzuki mad]

OK, I'm as English as they come, so just humour me ........

Its unusual for a head gasket to fail at the same time on those two cylinders. If you had said 2 and 3 or just 1 or 4 I would have said 'Yes' but also check the HT leads and ignition system. Having read the compression test figures it does seem like you lost compression.

Your saying that the oil leak is from the 'cam box gasket' (rocker box here in the UK) which would not interfere with the compression.

After the compression test and putting oil in can you see any signs of oil seeping out from between the gasket?

Suzuki mad.

[nabrams]

It is true that low valve clearances will lead to LOW compression - and this is the most common cause of LOW compression, and symptoms mainfest gradually. BUT: You have sudden, ZERO compression and you have visual evidence of major leaks in the head area. You've blown your head gasket - this DOES happen, especially on older bikes.
Of course, once you put everything back together again you WILL need to make sure all valve clearances are to spec.

[relic-rider]

The only other options for sudden loss of compression are a holed piston(s) or bent valves from a skipped timing chain. In any of the scenerios you are going to have to pull it apart, so get to it and let us know what you find.