1975 gt750 blowing oil out of vent tube
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- Still in the Driveway
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- Suzuki 2-Strokes: 1975 gt750
1975 gt750 blowing oil out of vent tube
New to the site hello. I have a 75 gt750 that I picked up a few months ago I got it going everything is working good other than it's blowing transmission fluid out of the breather tube I suspect it's the crankshaft seals leaking pressurizing the transmission oil was wondering if anyone knows of a good place to have the crankshaft rebuilt thanks
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- Yeah Man, the Interstate
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- Suzuki 2-Strokes: suzuki gt 550j
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Re: 1975 gt750 blowing oil out of vent tube
Hi and welcome to the forum. First before you start tearing the motor down. Drain and measure the oil if there is too much in there that's where it comes out. If that is okay you need to get someone trustworthy to do a leak down test to make sure that is the problem. The test puts a small amount of air into the crankcase to see if the seals hold pressure or leak. This will save you a lot of work for nothing if it isn't the seals. I'm sure someone from your side of the pond will be along shortly with a crank recommendation 

98 carb Blackbird and GT550j
- jabcb
- Moto GP
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- Suzuki 2-Strokes: 69 T350 thru 75 GT750
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Re: 1975 gt750 blowing oil out of vent tube
Bill Bune has done lots of Suzuki cranks & is highly recommended.
http://www.billbune.com/index.html
http://www.billbune.com/index.html
BAS (Bike Acquisition Syndrome) - too many bikes but have room for more
Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
Suzuki:
GT750 2x75
GT550 72 & 75
GT380 72
T500 69 project & 73 project
T350 69 & 71
Honda 85 CB650SC & 86 CB700SC
09 Triumph Bonneville SE
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- Still in the Driveway
- Posts: 3
- Joined: Sun Aug 23, 2020 6:05 am
- Country: United States
- Suzuki 2-Strokes: 1975 gt750
Re: 1975 gt750 blowing oil out of vent tube
Hey I appreciate the info I checked oil level and it is low now I lowered it and it didnt start coming out as bad until higher rpm and speed just did a leak down and have air coming out of vent tube so pretty sure crank seals I guess it is time to pull apart and I will contact bill bune next week appreciate that info also
1975 re5
1775 gt750
1973 t500
1975 re5
1775 gt750
1973 t500