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Cylinder base gasket leak gt 500

Posted: Tue May 12, 2015 2:43 am
by monclar
Hallo to everybody,
i'm new in this forum and i'm from italy. Last year i got a suzuki gt 500 A wich i full restored but now i've seen that from the bottom of the left cylinder there is a little leak of oil. Any suggestion?Do i have to put down all the motor and change the the gasket?Taking a look closely i see that the gasket is not perfetcly in this position. Could be a problem for the motor running in this way?Thank to all you.
Great forum!

Re: Cylinder base gasket leak gt 500

Posted: Tue May 12, 2015 7:35 am
by jabcb
Where is the leak & what does the oil look like?
It might actually be fresh oil from an oil line leak, or muck from the exhaust.

Re: Cylinder base gasket leak gt 500

Posted: Tue May 12, 2015 2:59 pm
by monclar
The leak is from the base of the cylinder front side. There are not leaks from oil lines and the oil is fresh. Maybe it could be the gasket?

Re: Cylinder base gasket leak gt 500

Posted: Wed May 13, 2015 1:00 am
by Craig380
How small is the leak? Do you see drops of oil, or is it just a little 'wet'?

First, I would check the cylinder head bolts are correctly torqued. Do not loosen them, just use a torque wrench to check the bolts are at the correct torque setting.

Re: Cylinder base gasket leak gt 500

Posted: Wed May 13, 2015 6:19 am
by monclar
Thank you for the reply, after the last time I rode the bike i saw a little trace of oil on the ground around the base of cylinder it was wet. I also saw the gasket a little out from the base. I'll try torquening.

Re: Cylinder base gasket leak gt 500

Posted: Wed May 13, 2015 9:23 am
by titan performance
Can't say I have ever seen a base gasket leaking before.....but only a 15 minute job to put a new one on anyway...

Re: Cylinder base gasket leak gt 500

Posted: Wed May 13, 2015 9:46 am
by monclar
15 minutes?!i pay to you the plane from England to Italy!
Coul'd I have to take away the head pistons and so on..

Re: Cylinder base gasket leak gt 500

Posted: Wed May 13, 2015 3:53 pm
by GT750Battleship
:shock: Hi,15 minutes !!! I'd like to see that :oops:
Cheers,
Roger

Re: Cylinder base gasket leak gt 500

Posted: Wed May 13, 2015 5:58 pm
by ConnerVT
On the T500, 15 minutes may be a quick reasonable estimate, if you have a little practice. It takes me just over an hour to pull both carbs, re-jet them, install, and kick the bike over (and I always pull the battery box and air box when I do that job).

For a cylinder base gasket --

- remove seat
- remove gas tank
- remove spark plug lead
- remove carb from intake boot
- remove exhaust flange bolts, move exhaust header from exhaust port
- remove 8 head bolts
- remove head and head gasket
- remove cylinder and base gasket

All can be done with engine on the bike. It's not a water buffalo. The cylinder comes off pretty easy. You'll want the piston to be near BDC, else the piston wont clear the bottom of the cylinder before the top hits the frame.

Reinstall is the reverse of the above. A liberal coating of oil on the cylinder walls is a good thing. Tricky part is keeping the rings lined up with the locating pins, and compressing them when sliding the piston back in the cylinder. Growing a third arm helps a lot. You will want to replace both the base and head gaskets. Exhaust gasket, too, if you have one.

Re: Cylinder base gasket leak gt 500

Posted: Thu May 14, 2015 1:34 pm
by titan performance
Apologies.....should have said 15 minutes off, and then 15 back on. (obviously assuming the jug is free).

Re: Cylinder base gasket leak gt 500

Posted: Fri May 15, 2015 8:15 am
by Coyote
Suzuki recommends no sealer of any type on the base gaskets Should go on dry.

Re: Cylinder base gasket leak gt 500

Posted: Mon May 18, 2015 4:53 am
by monclar
ConnerVT wrote:On the T500, 15 minutes may be a quick reasonable estimate, if you have a little practice. It takes me just over an hour to pull both carbs, re-jet them, install, and kick the bike over (and I always pull the battery box and air box when I do that job).

For a cylinder base gasket --

- remove seat
- remove gas tank
- remove spark plug lead
- remove carb from intake boot
- remove exhaust flange bolts, move exhaust header from exhaust port
- remove 8 head bolts
- remove head and head gasket
- remove cylinder and base gasket

All can be done with engine on the bike. It's not a water buffalo. The cylinder comes off pretty easy. You'll want the piston to be near BDC, else the piston wont clear the bottom of the cylinder before the top hits the frame.

Reinstall is the reverse of the above. A liberal coating of oil on the cylinder walls is a good thing. Tricky part is keeping the rings lined up with the locating pins, and compressing them when sliding the piston back in the cylinder. Growing a third arm helps a lot. You will want to replace both the base and head gaskets. Exhaust gasket, too, if you have one.
Thanks for the reply, yesterday i saw that one head bolt (not shouldered) is not at the torque.. in fact i believe that i have to repair one THREAD of the cylinder head..That's why i had my leaking at the base? Well now I'have to repair it with the helicoil. Did someone has useit before on the cilinder?

Re: Cylinder base gasket leak gt 500

Posted: Mon May 18, 2015 4:57 am
by monclar
titan performance wrote:Apologies.....should have said 15 minutes off, and then 15 back on. (obviously assuming the jug is free).
:up:

Re: Cylinder base gasket leak gt 500

Posted: Mon May 18, 2015 9:05 am
by titan performance
Failure of the M8 14mm bolts is common, when people over tighten them into the aluminium thread. However, this stripped thread is not going to be the cause of your base gasket leak. We have repaired lots of these threads over the years, and to be honest, I prefer the time-cert to a heli-coil.

Re: Cylinder base gasket leak gt 500

Posted: Wed May 20, 2015 4:46 am
by rngdng
ConnerVT wrote:
All can be done with engine on the bike. It's not a water buffalo.

You can do this job on a Buffalo on the frame also. It's a PIA, but it can be done.


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