Idles fine. Runs really lumpy. Help please

Carbs; K-jet; Tanks; Lines; Filler necks, Senders; aftermarket fuel systems; Exhausts and Manifolds;air filters - standard and aftermarket
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dixy42
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Idles fine. Runs really lumpy. Help please

Post by dixy42 »

Recently my gt2 has been playing up. It starts fine and idles well but when you go to pull away the revs drop dramatically almost to the point of stalling. When I have pulled away if I have my foot lightly on the accelerator it is really lumpy (real bad kangaroo'ing) but if I put my foot all the way down it will lurch back for a second and then run fine. It's starting to annoy me as it does it in every gear. Would really like some advise on this guys if any one can help. Thanks in advance.


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bengould
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Re: Idles fine. Runs really lumpy. Help please

Post by bengould »

Hi,

The first thing I would check is the fuel tank, look for small bits of rust.
Then I would be looking at the rubber base that the carb mounts on.
Then check all the vacuum lines, the timing, spark pugs etc.

You will find lots of information on here about rust in the tank it is a common problem and I would guess the most likely culprit.

Ben.


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tinkerbel
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Re: Idles fine. Runs really lumpy. Help please

Post by tinkerbel »

Also :hi: check that if you have an inline fuel filter, if not put one in, I also carry a spare one.


dixy42
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Re: Idles fine. Runs really lumpy. Help please

Post by dixy42 »

Cheers guys I will check everything and let you know how I get on.


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james butler
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Re: Idles fine. Runs really lumpy. Help please

Post by james butler »

ive had these symtoms and were assotiated with a rotting filler neck, bits of rust in the tank had got past my inline filter and had lodged in the jets of the carb.
take the jets out and give them a clean.
should run ok then. but you will have to find where the rust come from and at the very least put a fuel filter in line


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dixy42
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Re: Idles fine. Runs really lumpy. Help please

Post by dixy42 »

Does anyone have a workshop manual for gt2 in a PDF file?


dixy42
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Re: Idles fine. Runs really lumpy. Help please

Post by dixy42 »

Does anyone have a workshop manual for gt2 in a PDF file?


dixy42
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Re: Idles fine. Runs really lumpy. Help please

Post by dixy42 »

Well I have changed inline filter,sparks,leads,dizzy and rotary arm. No change so far....


Nate
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Re: Idles fine. Runs really lumpy. Help please

Post by Nate »

what carb is fitted? pierburg or weber? if weber, clean the filter at the carb inlet (17mm nut under the inlet pipe) if it has white fur in it, you've probably got water getting mixed with the fuel somewhere - check for rusty tank and/or filler neck

check timing belt is still correctly tensionned. mine gave similar symptoms when the belt was dangerously loose!

check the jets in the carb are clear - unscrew them carefully and blow them thru with carb cleaner. DO NOT POKE STUFF INTO THEM to clean an obstruction

check fuel hoses are in good condition. if they look like they are perished, replace them. it is also possible for them to collapse internally, partially blocking them

check swirl pot is clear and free flowing

check fuel pump is delivering a good amount of fuel

take obvious precautions when working with fuel, no smoking, well ventilated blah blah blah health and safety. heard another story this week of car going up in flames when the owner was messing with the fuel system in his garage, fag in his mouth. the guy lived, but he ain't gonna be able to work for a long time


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dixy42
Posts: 37
Joined: Fri Jul 06, 2012 6:16 pm
fill in the right answer: 15
Location: Flitwick, Bedfordshire

Re: Idles fine. Runs really lumpy. Help please

Post by dixy42 »

Turns out that the carb had given up hope. Replaced it and now she runs sweet as a nut. Touch wood :)


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