fuel problems maybe?

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cadetchris
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fuel problems maybe?

Post by cadetchris »

the engine has developed a new proble, which only accassionally happens.
when i start the engine it sometimes run quietly and very slowly, if i open the throttle, nothing happens, it still runs slowly and quietly, but when i take my foot off the peddle, it runs for a second or two then dies.
i will do this once or twice in a row and then third time it starts and runs wonderfully.
its not the fuel pump as this taps away happily, the carb is all nice and clean and the choke is set up nicely.
so it has me stumped.
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Post by mogbob »

cadetchris
A few ideas.
Are both accelerator and choke cables operating freely and returning to rest properly ? Are the cables fixed properly, i.e not slipping through the clamp ? Return spring attached.Linkage on the carb lubricated and un-obstructed ?
Carb ..." nice and clean " but does the piston drop freely if you lift the pin on the side... time and time again ?

Bob
bmcecosse
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Post by bmcecosse »

Perhaps the idle speed is just TOO slow - for winter conditions! Lift it slightly.
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cadetchris
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Post by cadetchris »

had a fiddle with it today, checked all the linkages and the choke and accelarator cable and found all tight and in good order.
i gave it a drive and it pulled and started fine.
However, when i came out of the shop and tried to start it, it did the same as usual. a slow idle with no power and very quiet. opened the throttle and still nothing in the form of power or incrase in revs.
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Post by bmcecosse »

Sounds like a sticking piston (in the carb) to me!
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cadetchris
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Post by cadetchris »

could well be. ill whip it out tomorrow and give it a nice clean down. hopefully that should fix it
cadetchris
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Post by cadetchris »

right, it did it again today, the carb is all clean, the timing is good, the plugs are clean, the head has been rebuilt and all things are connected, so why why why is the car still doing it?
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Post by dalebrignall »

have you got the right oil in the carb
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cadetchris
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Post by cadetchris »

could be the problem, i have used 3-in-1 oil and at other times, i have used normal engine oil. what would the "ideal" oil be (that is readily available)
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Post by MColes »

I always use 3-in-1. Which I believe is the oil that should be used.
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cadetchris
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Post by cadetchris »

i thought it was the best option, cheap, light and not to thick
cadetchris
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Post by cadetchris »

just had a conversation with my brother, he said it may of be due to moisture in the dizzy and leads.
could this be right?

(bearing in mind, this boy destroyed the diff by doing donuts in the thing, so his wisdom is always taken with a bucket of salt)
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Post by MarkyB »

Check that the points haven't closed up.
cadetchris
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Post by cadetchris »

it did it again today, turned the key, engine turns over but dosent go.
turn the key, floor the accelerator and the engine runs slowly and eventually dies.
this happens several times and then the battery runs out of juice and i give up.
hours later, turn the key and it starts first time is running well.

so, why is it doing this? it is going to catch me out at some point and ill be stuck
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Post by bmcecosse »

Could well be moisture problem - dries out later. But no point playing guessing games - you need to determine if there is fuel going in - and is there a decent spark ? And - are the spark plugs ok - and are they NGKs ?????????
Last edited by bmcecosse on Thu Dec 03, 2009 5:19 pm, edited 1 time in total.
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cadetchris
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Post by cadetchris »

their is deffinetly petrol getting in to the carb, a nice strong blue spark, and the plugs are nice and clean and set right. as for the NGK bit, they are just standard champion plugs.
would a new set of NGK plugs be of benefit?
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Post by bmcecosse »

NOOOOOOOOOOOO :o

If there was spark and fuel - it would run. Obviously one is going AWOL - most likely the sparks. The damp theory would be my favourite. Try cleaning dizzy cap/HT leads/rotor arm spotlessly - and keep them indoors in the warm/dry overnight. Then fit them to the car - does it start/run ok ???
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cadetchris
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Post by cadetchris »

ill give that a try tonight, hopefully it will all work, if not back to the drawing board
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Post by eastona »

Could be running too rich? maybe use less choke?

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cadetchris
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Post by cadetchris »

AH HA, got it
it did the same today, running slowly etc. i pinned down the accelerator peddle with the krooklock, got out and had a fiddle. seeing nothing disconnected or broken, i undid the dash pot and the revs picked up and all was well (except the very loud noise initally) after that it ran beautifully, so i have cleaned out the dashpot, and the float with the needle attached to the bottom and its worked (so far) pefectly, so could of it just been a dirty/very dirty carburettor?
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