'86 GS550ES Oil Leaks

[SirFoxx]

Hello--

I recently picked up a new-to-me gs550. It was not running when I got it, but a few fixes later it starts and runs fairly well. However, this thing is leaking oil pretty badly, and has a bit of a tick to it. On the front side of the motor, it looks like it may be dripping oil out of the #2 and #3 exhaust header, and on the back side, it looks like its leaking from the banjo fittings for the oil lines. The oil likes to accumulate around the starter since it is a low spot, and it drips out around the kickstand. I think the banjo fitting just needs a new crush washer, but as for the header, could it be leaking from around the port, or is it leaking out of it? Also, is there anything on the back side of the motor that might leak oil? I have absolutely no idea on the past on this bike except for the fact its been wrecked on both sides. Though whoever fixed the stator cover did a fairly decent job.

As for the tick, I can't tell if its valves or if its something else. I did my best trying to adjust the valves using the 16-valve guide on bikecliff's site, but it still has a bit of a tick (it did seem to get better / less tick-y). Is there anything else that might tick? I will check and readjust again when the replacement valve cover gasket arrives.

Heres a quick video of it and trying to find the oil leak / listening for the tick.

 

[Redman]

On vidio I could not really see about the "exhaust header" oil leak, and I am not that familiar with the 550s. But on most GS 4 cyclinders, an oil leak in that general area (front, center, upper) could be more from the tachometer drive (if it has such for a mechanical tachometer).
If it is an oil leak from the tach drive unit, be aware that there are two oil seals in there, although on some year/modle the microfische only shows one of them, so need to also look at other year microfische.

.

 

[BigD_83]

The oil line fittings on these are a known potential leak point. They are no longer available new, at least the last time I looked.

EDIT- available in some places. Babbit's has them:

http://www.suzukipartshouse.com/oemparts/a/suz/50d3f896f8700230d8b4cf4a/cylinder

It could just be due to crush washers being overtightened, but it's more likely the 32 year old rubber is cracking.

Another potential leak suspect on the back side of the motor is the cam chain tensioner.


I find ticks difficult to track down. A mechanic's stethoscope or using the pommel of a long screwdriver can help isolate the sound. Even a slight leak in the exhaust or a loose header can make a ticking sound that appears to come from the valve train.


EDIT- looks cold there already. Your video goes over the trouble spots a little too quickly to focus on any one area. Is that exhaust we're seeing, or oil-smoke from the leak?

 

[SirFoxx]

The oil line fittings on these are a known potential leak point. They are no longer available new, at least the last time I looked.

EDIT- available in some places. Babbit's has them:

http://www.suzukipartshouse.com/oemparts/a/suz/50d3f896f8700230d8b4cf4a/cylinder

It could just be due to crush washers being overtightened, but it's more likely the 32 year old rubber is cracking.

Another potential leak suspect on the back side of the motor is the cam chain tensioner.


I find ticks difficult to track down. A mechanic's stethoscope or using the pommel of a long screwdriver can help isolate the sound. Even a slight leak in the exhaust or a loose header can make a ticking sound that appears to come from the valve train.


EDIT- looks cold there already. Your video goes over the trouble spots a little too quickly to focus on any one area. Is that exhaust we're seeing, or oil-smoke from the leak?

Cool. I will probably replace the crush washer and go from there. I think the cam tensioner has a tiny leak, but not enough to leave a pool of oil on the back side of the motor. As for the front, I have an electric tach, so there is no mechanical tach to leak. I apologize about the video, I was focusing more on the tick than the oil leaks. After I replace the crush washers and valve cover gasket, I will probably degrease it and use some foot powder to try and locate the oil leak. The smoke is from it leaking (I hope). It's was in the 70's in the video. I have an eerie feeling that I may have to replace the head gasket (whats a base gasket?).

Also, I'm kinda curious, what are the main differences between the gs and the gsx 550?

 

[Carter Turk]

(whats a base gasket?).

The gasket at the base of the cylinders.

Pretty much have to replace that if the head gasket is being replaced or risk a leak down the road if reused.

The differences between the GS visually are box section frame, dual carbs, vs. 4, different engine architecture, mono-shock, 16" front wheel, clip-ons.

 

[SirFoxx]

The gasket at the base of the cylinders.

Pretty much have to replace that if the head gasket is being replaced or risk a leak down the road if reused.

The differences between the GS visually are box section frame, dual carbs, vs. 4, different engine architecture, mono-shock, 16" front wheel, clip-ons.

Which model has the 2 dual carbs?

 

[BigD_83]

Which model has the 2 dual carbs?

Ours do (83-86(?) GS550E, ES, EF). You'll see it listed as a GS550es in North America, but in Europe they are badged GSX. I believe there was a 500 version in Europe as well, and the model carried on a bit longer overseas, maybe as late as '87 or 88.

I'm not aware of any other North American GS model with the dual (aka siamese) carb.

 

[Brendan W]

Don't know what the head casting is like on the 550 but on the 850 if the cam cover gasket leaks, particularly on the hidden inside areas near the chain tunnel, the oil emerges just above the exhaust ports.
I would get the tank off a have a look.

 

[SirFoxx]

Well I think I may have a more serious problem. I replaced the valve cover gasket and replaced the crush washers. That fixed 90% of the oil leaks. However, the bike smokes real bad. Could it be a case of it needing the head redone, or do you think it needs rings as well? Also, is there a rebuild guide for these oddball mikuni carbs? I can't even find what model they are :/


edit:found the model in the manual. should have looked there first lol

 

[Brendan W]

Rule of thumb, if the smoke is there for a minute or so after startup it could be just the valve stem seals.
Oil runs down into the combustion chamber after shutdown and burns off fairly soon after the next start.
Smoke present all the time could be rings.
How many miles are on the bike?
My rings and bores were very good at 45000.
If it has been leaking out the front for a while it will take time to burn off unless you clean it all.

 

[Cipher]

you might consider replacing the cam cover bolt o rings as well