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Fueling troubles?


wild foamy
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Hey peeps

I need to pick some brains... Basically my mini is feeling poorly, with the choke fully out and no throttle applied it revs its little 1275 head off, once warm it will run without choke but hesitates and splutters under load, this leads me to believe it's a fueling issue but where do I start? Also you can see the heat rising from the exhaust even at idle slim pretty sure it's lean...

Any help appreciated, :/

Steve

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Fuel injector Cleaner ...... once a month or so......do this with my Cad --runs like a champ.

Also check your fuel filter.....maybe replace it IF it's somewhat accessible.

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Clean the air filter and check the vac to the heat rise on the manifold heat riser choke. make sure the choke is pulling off as the temp rises.

make sure all the linkage is well lubed and free to the choke.

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If it's a full manual choke forget it,we must have got the delux models.

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I take it you have whipped the carb off to check the jets inside?

Next for me would be the fuel pump. Check the delivery.

C'mon steve these engines make your old DT seem modern.

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I had a fuelling issue with my mk111 'tina.

turns out there was 1 spec of crud in the float bowl, which got sucked to the main jet at high speed.

carb strip I'm afraid foams

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I had a fuelling issue with my mk111 'tina.

turns out there was 1 spec of crud in the float bowl, which got sucked to the main jet at high speed.

carb strip I'm afraid foams

my dad had this issue with his drewps , it must have been common , the stupid thing falls back down when you stop , then reacures later.
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:offtopic: OK what about 4 carbs ie 1200 fj carbs longer intakes????????????????????????????????////// think about it ?
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Not sure about 4 carbs, but my old twin carbs I had on my old MG Midget and MG1100 would bolt onto a mini engine no problem.

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Check that someone hasn't fitted an electric fuel pump. If it is still the manual one, unbolt it and see if, when you pump the lever, it pumps fuel. When these go the old a series engines just use compression to suck fuel out of the tank. The su carb is normally reliable. Check the choke flap is closing when the choke knob is pulled. Get a mate to put their hand over the air intake and partially block the air flow at start up. Then it is down to compression testing. I would guess your head has not been upgraded to unleaded and this can burn out the valves.

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Mini- what?

Mini moto?

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Advance- retard pipe off at manifold,,,, minis had electric pump in boot :eusa_think: , if i mind correctly,,

i had twin S,U"s on me morris minor, with healy sprite engine, :drive:

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