GT250 Engine rebuild, but not starting

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jabcb
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Re: GT250 Engine rebuild, but not starting

Post by jabcb »

There should be a 5-digit number stamped on the carb bodies. It might appear as 3 digits with the other two digits below them.
The number is the second part of the parts # & can be used to figure out what model & ~year the carbs are from.

Suzuki didn’t stamp the first part of the part # on the parts because that tells you what type of part it is & you all ready know that.
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
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09 Triumph Bonneville SE
Micron
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Suzuki 2-Strokes: GT 250 1975
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Re: GT250 Engine rebuild, but not starting

Post by Micron »

jabcb wrote:There should be a 5-digit number stamped on the carb bodies. It might appear as 3 digits with the other two digits below them.
The number is the second part of the parts # & can be used to figure out what model & ~year the carbs are from.

Suzuki didn’t stamp the first part of the part # on the parts because that tells you what type of part it is & you all ready know that.

Where do I find the numbers? Also is there a chart or guide that tells me what's what?
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jabcb
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Joined: Mon Dec 13, 2010 4:32 pm
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Location: southwestern Pennsylvania

Re: GT250 Engine rebuild, but not starting

Post by jabcb »

Use an online parts system for your bike:
http://www.partzilla.com/parts/search/S ... parts.html

The carb first 5 digits are: 13201 for RH & 13202 for LH.
Suzuki made some jetting changes, so there are early and late carbs.
Early carbs are: 13201-18660 & 13202-18660. (Expect some errors in these 40 year old part number manuals.)
Late carbs are: 13201-18661 & 13202-18661.

The numbers are on a flat or nearly-flat surface where it was easy for Mikuni/Suzuki to stamp the numbers.
Look for 18660 or 18661. Carbs are correct for a GT250A/B if you find it.
#s are likely near the fuel hose tap, vacuum hose tap & choke mechanism.

Here is an example from an eBay listing:
http://www.ebay.com/itm/Suzuki-GT250-GT ... 3100465192
Image
This carb has number 18654.
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
User avatar
jabcb
Moto GP
Posts: 4240
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: GT250 Engine rebuild, but not starting

Post by jabcb »

Here is another example that shows where to look.
This carb is for a GT250A/B in Europe. Carb jetting for Europe was sometimes different, so the parts #s would be different.
http://www.ebay.com/itm/Suzuki-GT250-A- ... Sy&vxp=mtr
Image
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
Micron
On the street
Posts: 49
Joined: Thu Aug 03, 2017 1:30 pm
Country: United Kingdom
Suzuki 2-Strokes: GT 250 1975
Location: Essex, England

Re: GT250 Engine rebuild, but not starting

Post by Micron »

Thanks, I will take a look.
PS big picture :lol:
sportston
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Re: GT250 Engine rebuild, but not starting

Post by sportston »

Micron, I have sent you a PM. Give me a call if you want to meet up this weekend for a diagnosis and remedy session.
Just been thinking about your problem. Here are a few questions to ponder:-
Have you checked the baffles in the exhaust? Have they been decoked recently?
Are the jets in the carbs the ones listed for your bike?
Is your oil system free of air locks?
Micron
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Suzuki 2-Strokes: GT 250 1975
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Re: GT250 Engine rebuild, but not starting

Post by Micron »

sportston wrote:Micron, I have sent you a PM. Give me a call if you want to meet up this weekend for a diagnosis and remedy session.
Just been thinking about your problem. Here are a few questions to ponder:-
Have you checked the baffles in the exhaust? Have they been decoked recently?
Are the jets in the carbs the ones listed for your bike?
Is your oil system free of air locks?
When I took the engine apart, I took the baffles out of the exhausts, but I can't remember if I actually decoked the exhausts?
I will need to check the jet size, I think I need to confirm what carbs they are first?
I believe it is, free of air, as I did bleed it as described in the Haynes manaual, but again, is there an easy check?

Thanks
Trev
sportston
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Re: GT250 Engine rebuild, but not starting

Post by sportston »

Micron wrote: I believe it is, free of air, as I did bleed it as described in the Haynes manaual, but again, is there an easy check?

Thanks
Trev
Unless you have clear pipes that you can see through, then no. If you followed the Haynes manual procedure then I am sure it is fine.
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