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weewillie

weewillie

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any opinions on the gunson colortune. I have one and am trying to get the midget running after 15 years idle. Can get it started and then it runs at about 1500 rpm, trouble then is when I shut it off it wont start again until I take the plugs out and blow them off and the fuel out of the cyls. Think the timing is off a little also.
 
I've used a pair of 'em for decades.

Sounds like you need to do some more gross adjustment first tho, Will. Float levels good? Needle/seat working correctly? Throttle linkage allowing full shutting of the butterflies?

Gotta get the idle down to 500~800RPM and timing correct before the colourtune will be of use.
 
thanks Doc, jets flush with the bridge, set to 12 flats down,11/2 on the throttle adjusting screw. However 1 piston is a bit higher than the other and I have a feeling that 1 carb is a tamperproof one and one not.
 
Mis-matched? Ooof. Are the carbs' throttle linkages "matched"? IE: loosen the cross-link's "locks" on one or the other, back the idle screws off and be sure you have the same throttle (closed completely) setting on both before tightening linkage down again. Would you have one carb with the "flutter-valve" in the butterfly and one not, mebbe?!?

Pix may help here, Will.
 
No no flutter valve , thought I had linkages matched however will check when I go down to the shed in a couple of hours. 1 carb has like an adjusting lever on it ?. Will take some pics when I go down. I have to go get a battery charger as the one I have is about 30 years old and and is pooched.
 
You say one piston is higher? This at idle, or not running?

That "lever" has me confuzzled.

Is your timing right and the mechanical advance working? It sounds "sloppy", I.E. rich, and like the timing/advance isn't right.
 
Willie - if you need an extra set of hands, give me a holler.
 
JPSmit said:
Willie - if you need an extra set of hands, give me a holler.
Click to expand...

Good, JP!! The thing is pushin' raw fuel outta the exhaust ATM.

...and my arms are too short to reach the beast. :wink:
 
Thanks guys, however I just pulled the alternator as it wasn't charging so I will get it rebuilt first.

pistons down when not running and one is higher at high idle which makes me think it is a non tamperproof one and needs to have the jet adjusting nut turned down 3 full turns or 18 flats.

Fuel pump is a facet is it possible there is too much fuel pressure?
 
Will said:
needs to have the jet adjusting nut turned down 3 full turns or 18 flats.
Click to expand...

That'll make it even more rich.
 
Disengage the throttle shaft coupling, set the carbs to be in synch by tweaking the idle screws and listening to each one, so the "hiss" is equal. Shoot for a 700~800 RPM idle speed, then retighten the shaft coupling.

The Facet shouldn't be a problem if it's the low pressure one. There are two different types, low and high, IIRC.
 
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