GT250 won't start

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lammy1
Still in the Driveway
Posts: 3
Joined: Mon Jun 13, 2011 12:57 pm

GT250 won't start

Post by lammy1 »

hello all,

after reading some very nice topics on this board I got enthousiastic on getting my GT250A on the road.
I purchased it a couple off years ago for 250 Euro as a non runner.
I always liked those little bikes so I thought what the heck and bought it.
Initially I wanted to get it running, but there came something between it, buying a Scott 2-stroke 2 cylinder watercooled from 1928.
That bike was a dream that i thought I could never be reality, but it became reality.

Back to the Suzuki, this weekend I checked: the ignition; ontime checked with stroboscope light
cleaned the carbs ultrasone
checked compression when cold ; 8 bar +/- 110 Psi
put new plugs in

After all that I sprayed some breakcleaner in the carbs and tried to start it; nothing.
put some petrol in the tank and kicked it over nothing.
Checked with the strobe if I got sparks when the plugs are in the engine that was Ok.
So I fiddled along a saturday and sunday but nothing, once i heard a little cough.

i am now out off options what to do.
Has any one more options for me.
I was thinking piston ring worn out, but i have adequate compression,
Or the worst worn out cranckshaft seals, how can I check that?

thank you for your time.

Frank
the Netherlands

here some pics from my bike

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rbond
Yeah Man, the Interstate
Posts: 686
Joined: Mon Nov 24, 2008 12:22 pm
Location: Alexandria, La.
Contact:

Re: GT250 won't start

Post by rbond »

If it has been sitting up for a long time, there is a strong possibility the crank seals are gone. But first check that the mufflers do not have anything in them, rat's nest, bird's nest, etc. I have seen a few mopeds mysteriously stop running over a weekend, because of what we call mud dauber insects plugging up the tail pipe with dried mud for their nest!
lammy1
Still in the Driveway
Posts: 3
Joined: Mon Jun 13, 2011 12:57 pm

Re: GT250 won't start

Post by lammy1 »

I also tried to start it without the exhaust nothing.
Also when I wanted to start the engine on petrol the plugs were wet so there is fuel coming in.

the thing is driving me crazy :(

frank
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jabcb
Moto GP
Posts: 4311
Joined: Mon Dec 13, 2010 4:32 pm
Country: USA
Suzuki 2-Strokes: 69 T350 thru 75 GT750
Location: southwestern Pennsylvania

Re: GT250 won't start

Post by jabcb »

Try bump starting it. Since you won't have any hills to speak of, it would help if you get a second person to push.
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
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Cliff
To the on ramp
Posts: 476
Joined: Sun Dec 14, 2008 9:34 am
Country: Canada
Suzuki 2-Strokes: Original owner GT550L
Location: Whitby, Ontario

Re: GT250 won't start

Post by Cliff »

Did you try switching the plug wires at the plugs?
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tz375
Moto GP
Posts: 6213
Joined: Mon Nov 03, 2008 10:47 am
Location: Illinois

Re: GT250 won't start

Post by tz375 »

Lammy, Let's go back to basics.

The bike has been sitting for several years and was purchased as a non runner. Yes?

So we need to just check things from one end to the other. Some, or all of these may have been done, but just to be sure use it as a check list and work through each section one at a time in a logical manner.

Fuel System
Clean fuel tap and filter
Strip and clean carbs
reassemble and adjust carbs
Check air filter and filter housing and clean or replace as required
Check intake boots (rubbers) for cracks and air leaks

Electrical system
Replace battery
Check all ground (earth) leads and connections - clean as required
Check all electrical connections in the ignition circuit and replace/clean as required
Check and clean points
Set points gaps and static ignition timing
Replace spark plugs
Replace plug caps and shorten HT leads by 6mm or so
Test for spark at both plugs

Exhaust system
Remove and check baffles - clean as required

Motor
Drain and replace transmission oil
Drain and replace CCI oil injection oil
Clean out oil lines of old viscous oil.
Check compression again
Pressure test for air leaks 6psi of 6 minutes +ve and -ve pressures

Then try to fire it up again if/when all the above test out as OK.
lammy1
Still in the Driveway
Posts: 3
Joined: Mon Jun 13, 2011 12:57 pm

Re: GT250 won't start

Post by lammy1 »

So we need to just check things from one end to the other. Some, or all of these may have been done, but just to be sure use it as a check list and work through each section one at a time in a logical manner.

Fuel System
Clean fuel tap and filter Done
Strip and clean carbs Done
reassemble and adjust carbs Done
Check air filter and filter housing and clean or replace as required Done
Check intake boots (rubbers) for cracks and air leaks Done

Electrical system
Replace battery Done
Check all ground (earth) leads and connections - clean as required Done
Check all electrical connections in the ignition circuit and replace/clean as required Done
Check and clean points Done
Set points gaps and static ignition timing Done
Replace spark plugs Done
Replace plug caps and shorten HT leads by 6mm or so Done
Test for spark at both plugs Done

Exhaust system
Remove and check baffles - clean as required Done

Motor
Drain and replace transmission oil Done
Drain and replace CCI oil injection oil Done
Clean out oil lines of old viscous oil. Done
Check compression again Done
Pressure test for air leaks 6psi of 6 minutes +ve and -ve pressures
I want to do the pressure test as described here viewtopic.php?f=2&t=3137&p=97825#p97825

But that will be tomorrow or the next day.

tz375 thank you for the list; most off the things I did already.
This list is a great to-do list for first starting up a secondhand bike

Frank
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