leaking issues on gt380

[apoole6]

Having issues again with oil pump leaking and also clutch cover seems to leak a little by the kickstart lever. I have used Permatex semi permanent gasket sealant (I also used this on crankcase). I was told Three Bond sealant is what I should use but so far I don't see oil leaking out of the crankcases just the clutch cover and oil pump. I am still concerned about the seals or if the transmission oil is leaking through the crank but im not sure. The bike idles fine and pulls well but as I get passed 5k rpm it vibrates somewhat and I don't believe it did it before(it might vibrate a tad bit more now). I bought a new clutch basket and hub since the one originally on there made a clunky noise as you pull out from a stop in 1st gear and now that seemed to go away.

Anyways i'd like to get opinions on Three Bond gasket sealant. As far as the vibration goes it does it in the high rpms and down low its pretty smooth.

[Vintageman]

I'll take a stab.

I take it you recently spilt the crankcase halves. What did you do for work?

Oil leak Kick start. Of course the Kick start has a seal. Is it leaking here, bad seal. If you mean clutch cover case. If you left even a small piece of the old gasket (You did use a new gasket yes) it may leak due to a gap. Vibration. Something is not balanced well. CrankShaft? Clutch?

Also, Check for binding. Take plugs, turn crank by hand (somehow) so you can feel for any binding. If so cases or cylinders not torque correctly or aligned cylinders/head

Oil pump leak. Is it gear oil or two stroke oil. I think if gear oil may be gasket between pump and case also does tach screw in pump. Can't remember on that bike. If so rubber O ring on tach cable missing bad.

If gear oil the supply/oil line to from pump are loose or the nylon washer needs to be replaced.

[Coyote]

If gear oil the supply/oil line to from pump are loose or the nylon washer needs to be replaced.

Gear oil pump? That's a new one on me. I assume you mean the supply line from the oil tank (2 stroke oil)?

[apoole6]

When I split the cases the crank was bathed in oil on the bottom crank half. Originally motor turned over fine with good compression but I decided to clean the cases and inspect crank. New outer crank seals were put in.

It leaks trans. oil from the gasket in between the clutch cover and crankcase area by the kick start. Gasket was new not used but I also think the flat metal surfaces between the cover and crank case is not even which i'd assume could cause this.

As far as vibration I don't recall it doing it as much as it is now (although its not severe vibrations) when I took out the clutch basket and all that.

The oil pump (for the oil injection) is leaking I believe from the top part of it with the arm lever but it could be the plastic washers.

Cylinders and the heads are not leaking and I haven't seen the crankcase halves leak. I may bring it back to my local Suzuki shop who used to sell these and have them compression test, leak down,etc.

[apoole6]

It also seems to vibrate just a slight bit more when the bike is hot. I would like to say the clutch basket or something in there isn't tightened right or unbalanced??

[yeadon_m]

One source of vibration that is easily missed is a mis-mounting of the rear exhaust bolt to frame lug. It must 'float' and not be hard-mounted. May be worth checking that even when bolted up tightly, you can wriggle the pipes left and right a mm or so, and if not to insert some washers to make sure that the plot is free to move on that rubber mounting!
If the clutch hub nut is not tight enough, you often hear noises as much as get vibration (eg from meshing crank pinion to clutch basket gear teeth). I have had that piece of fun and tightening that big nut did eliminate those noises, thankfully.
Cheers,
Mike

[Vintageman]

apoole6,

When you took the clutch cover off and cleaned out the old gasket from both halves, did you find the old gasket came off easy for you? Most of the time I find that tar based black OEM gasket comes off hard... and if you leave a little high spot (like near align pin etc.) it leaves a gap and leaks.. that's what I mean

Sorry I dropped the word "or" at a minimum. I think faster than my two fingers can type... I should have wrote

is it gear oil or the supply/oil lines to/from pump?

I think under the pump is a gasket. If that leaks it may be gear oil not 2 stroke injection oil. Also not sure where crankcase vent is on that bike. Is it near the pump? If gear oil is leaking check these spots.

So I am asking if you know if it gear oil or 2 stroke oil. Maybe these oil are different color for example. Well, clean the area real good. then run briefly and look for where leak starts.

Yeadon_m has a good point about vibration causes. Do you feel it deeply in handle bars or do you more hear it like some external object is vibrating. A lot of times it is something like exhaust that is loose, broken fender mount, etc. when you can clearly hear it elsewhere. Not sure that helps... just look for loose items on bike. I find these kind of things at times when the bike is still and rev it briefly to your >5k rpm place it occurs

[apoole6]

It's definitely 2 stroke oil leaking for the injection pump cause when you lean the bike over to the right after running it for a little, you can see some running down from the small corner down the crankcase.

As for the gasket for the clutch cover, it came off easy for me. Actually in fact I saved it in a bag (even though I know reusing wont work) just in case. When I mounted a new set of stock pipes for my '75, I did tighten them kind of tight where it mounts near the passenger pegs. When it runs you can see (mostly the split pipes) vibrate. I'd figure rubber mounting them would be better than how they are mounted but I think you can "wiggle" them about a mm or so.

[Suzukidave]

If you can see the pipe hanger solid against the frame when they are mounted then the pipes are not " floating" on the rubber mounts in the frame . Use a spacer or small washers to get the pipe hangers off the frame and only solid mounted to the rubber carriers . This goes for any of the rubber mounted engines GT engines also

[Vintageman]

As far as leaking around clutch cover/kicker. You need to clean it up and then look for early signs of this leak. You did not say but I ASSumed and still do it is gear oil? (not what is coming down from 2 stroke oil pump?)

Thus, best once clean let it just set (center stand level better than side stand maybe) and look for leak source. If you drive wind will blow all around making origin hard to find. I assumed it is near or at the clutch cover based on post....why may even be oil drain plug washer for example. But, if you are correct about approximate origin and proves to be between the case and clutch cover, don't assume the fact the gasket come off in one piece none of it wasn't left stuck to the aluminum. look at that gaskets for pit holes/missing bits... if so where are they. But yes just may be elsewhere ...once you get er cleaned should find source. Not always easy I had (for a couple years) a small but definite gear oil leak on my R5 and it proved to be scratch in lower case under oil plug washer. It looked like was shifter gasket or sprocket gasket since I had only side stand and dripped there. In time once clean I saw it was at oil drain plug..., assumed the washer there was culprit (suppose to change each time removed yes... who does). New washer still leaked. put on my glasses and looked at things real hard.. saw scratch and fixed no more leak. My T500 had a crack in clutch cover... i'll keep that story short.

let us know what you find

[Cliff]

Tip for finding a leak. Clean and dry the area then sprinkle baby powder over it. The powder will stick and change colour on any moist/wet spot!

[apoole6]

It is obvious the oil pump leaks(not transmission oil, 2 stroke oil) blue 2 stroke in the back corner enclosed by the cover. I believe it still leaks from the top half of the pump(with the arm).


The clutch cover gasket still leaks in rear part of the clutch cover(end of clutch cover towards the bike of bike) in between gasket and metal.

[Coyote]

Under the oil pump cover there is a transmission breather / vent pipe. If the transmission is over filled or being pressurized by a bad seal, oil will come out of this vent and appear as a leak.

Of course if you are sure the oil is blue, that rules that out. So then pull the oil pump off and inspect all surfaces. The pump underside, upper and lower surfaces of the octopus.the condition of the six o-rings and the crankcase surface. Replace those o-rings if they are flat, cracked or hard. I always use new o-rings as a matter of servicing the pump. DO NOT use any sealer anywhere around the pump. That would certainly be asking for trouble. There is no separate gasket. The plastic octopus and it's 6 o-rings IS the gasket.
You said you think it may be leaking around the pump arm. That's not likely but to be sure, clean the pump body with thinner and patience. Wrap some cotton around the arm / body junction and take it for a ride. If the cotton becomes sopping wet with blue oil, you found the culprit.
For the clutch cover leak, take the cover to a machine shop and have it checked for flat.. You can check it yourself if you have a large enough piece of glass. Check it with a feeler gauge and check it for rock. Check iI for deep scratches. I hope you or no PO used silicone on these mating surfaces. Silicone is IMPOSSIBLE to remove. There is nothing known to man that will cut it. It turns into mega hours of work with a razor blade and worn out fingernails.
Anyway, the clutch cover leak should be easy to solve. They always drip from the lowest point, but that doesn't mean that's where it's leaking. Check under all the lower screws with a clean paper towel. You may find the leak is way forward of that drip point. If you can't get it to stop, I will explain the 'string' method.