Gt550 runs with choke

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JessC
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Re: Gt550 runs with choke

Post by JessC »

the pilot jets are so tiny in opening..should I try get from Keyster they look the same..... I did not use anything from there kit except for gaskets I know better than that
GTandcbr
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Re: Gt550 runs with choke

Post by GTandcbr »

Firstly I would not buy any jets from Keyster just stay safe with Mikuni. That's just my opinion. Secondly here is a video which may assist setting float level with Z1 tube
https://youtu.be/xnAMl5282WY" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;
Remember if the float level is slightly too low the jet will not pick up the fuel.
98 carb Blackbird and GT550j
JessC
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Re: Gt550 runs with choke

Post by JessC »

Float level looks good. I have the pilot jets from the Keyster kits.. I have not tried them.
Do you think maybe bad crank seals are causing this trouble? Bike does not smoke much when i get it to run. Who in the USA rebuild's the cranks?
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jabcb
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Re: Gt550 runs with choke

Post by jabcb »

GTandcbr wrote:...
https://youtu.be/xnAMl5282WY
...
Gas is around 3/4 the weight of water. The float sinks into the fluid deep enough to get the weight of displaced fluid equal to the weight of the float. So the float will sink deeper into gas than it would with water.

Using water to check the level will give an incorrect reading. But I haven’t done the comparison so I don’t know if this error is important or small enough to ignore.
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GTandcbr
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Re: Gt550 runs with choke

Post by GTandcbr »

Hi
Good info! Would be interesting to know the actual difference. My bike seems to run well and I used water.
Maybe next time the carbs are apart i will try a comparison.
98 carb Blackbird and GT550j
karl pa
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Re: Gt550 runs with choke

Post by karl pa »

JessC wrote:Do you think maybe bad crank seals are causing this trouble?
It is possible that seals are causing it, you can check seals by removing carbs and hold hand over carb boot checking suction while turning engine over, all three should have around the same suction.
Did you spray carb cleaner and air through pilot circuit to make sure everything is open? I heard that ultrasonic cleaning sometimes doesn't always get clear first time.
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JessC
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Re: Gt550 runs with choke

Post by JessC »

I bought a set of used carbs and cleaned the right side and center carbs. Bike is trying to run better but center cylinder is cold on exhaust.try's to fire when I put hand over mouth of carb. so back apart and let it soak more ,ultra sonic clean and float level check with a clear sight tube. Making slow progress :wth:
Jess
JessC
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Suzuki 2-Strokes: GT550
Location: California

Re: Gt550 runs with choke

Post by JessC »

bike still wants to run on left and right side center pipe only comes on with hand over mouth of carb. took bike for a few blocks hoping that it needed to be cleared out good.bike runs good after 5 grand on tach. not sure if it is carbs they are spotless in side with carb. cleaner thru all ports.
I'm thinking it is bad crank seals....not going to be able to make the "TWO STROKE EXTRAVAGANZA here in Los Angles Ca.
karl pa
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Re: Gt550 runs with choke

Post by karl pa »

Do you have good spark on plugs? I always like to check everything else first, unfortunately crank seals dry and crack after setting for years, you can do leak down test on cylinders to check the condition of them. One of my 750 acted similar, ended up being seal between two cylinders was totally gone.
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karl pa
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Re: Gt550 runs with choke

Post by karl pa »

JessC wrote: bike still wants to run on left and right side
Just so I understand, the left and right cylinders are firing? the center cylinder is not? if this is the case, I wouldn't think it's crank seals. If the center cylinder seals have issues, the left or right cylinder would also have issue.
Not sure if 75 has sris lines from crankcase to cylinders, if so did you check them that they are intact and working properly? if there is a problem with these, the cylinder could suck air in making a lean condition.
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JessC
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Re: Gt550 runs with choke

Post by JessC »

Thank you for the reply's bike has good spark I have not checked those lines yet doing to do a spay on intake rubber on center cylinder. yea really makes me wonder bike does not smoke much for the few times I rode it . guy I got it from put a crap load of oil in cylinders.. all that is burned off I think
GTandcbr
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Re: Gt550 runs with choke

Post by GTandcbr »

Modern 2 stroke oil doesn't smoke much these days. Especially fully synthetic.
98 carb Blackbird and GT550j
JessC
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Re: Gt550 runs with choke

Post by JessC »

BAD NEWS I found out the center choke plunger was not seating and letting gas weep to right cylinder.fixed that and did a vacuum test from back of carb held a vacuum.
Now center cylinder does not want to run as well as right side not running ...so it has to be bad crank seals.
Thanks for all the help !
Question WHO does good Crank Shaft seal work? I'm in California
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ConnerVT
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Re: Gt550 runs with choke

Post by ConnerVT »

Bill Bune Enterprises - https://www.billbune.com/
karl pa
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Re: Gt550 runs with choke

Post by karl pa »

JessC wrote: I found out the center choke plunger was not seating and letting gas weep to right cylinder
Not sure I understand, how did you determine gas weeping to right cylinder? and where was it cross feeding at?
JessC wrote:fixed that and did a vacuum test from back of carb held a vacuum
If it held a vacuum means crank seals are working properly.
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