Club126UK

Fiat 126 Chat => Fiat 126 Mechanical Problem Solving => Topic started by: Nurudin on July 04, 2006, 01:02:12 AM

Title: Funny stop
Post by: Nurudin on July 04, 2006, 01:02:12 AM

Hi all! Recently when I turn the key to stop the engine it jumps hard for a few times before it dies. Feels like its going to jump out of the car. Any ideas?

Title: Funny stop
Post by: fiatfsm on July 04, 2006, 12:08:44 PM

sounds like its running on... maybe your tickover speed is too high?

Title: Funny stop
Post by: ChrisRLewis on July 04, 2006, 01:08:30 PM

Check the contact point gap then the ignition timing. It may also be the spark plugs which are running to hot. Do them in the above order and check if it's cured after each stage.

Title: Funny stop
Post by: Bruce on July 05, 2006, 06:30:56 PM

in the olden days (after all the 126 is old technology) a decoke could cause this with a hot lump of carbon in the cylinder head igniting the mixture causing the engine to run on.

Title: Funny stop
Post by: Nurudin on July 05, 2006, 10:33:00 PM

I am sorry I don't know what is decoke.  I have also noticed that there is some backfire from the exhaust when I release the accelerator pedal

Title: Funny stop
Post by: Bruce on July 05, 2006, 11:08:47 PM

sorry what i meant was the car could need a decoke, plder cars using low quality fuel used to get a carbon buildup in the cylinder and around the exhaust valve. it the dark ages we used to have to clean this out periodically. It is possible to do this with redex

Title: Funny stop
Post by: paul harbinson. on July 06, 2006, 07:48:48 AM

Make sure the carburettor is tight on the studs.If it's loose it can make the motor run like a pig and backfire (too much air being sucked in).Mine dos'nt have a distributor and yet it "runs on" from time to time.

Title: Funny stop
Post by: PaulB on July 06, 2006, 03:15:14 PM

The carb tip is a good one - but beware that over-tightening the carb onto the head can create a similar problem - the carb base bends and creates an air-gap.

The base (or flange) bends very easily and it is a very common problem. Many people don't realise what a light touch it takes to reach a high torque, even with a small spanner.

To check if there is an air gap due to a bent carb, take off the carb, rub the  base with lipstick or similar and press it on a very flat surface like a piece of glass or a mirror.  the lipstick will leave a "footprint" on the glass so you can see where the gaps are. If  the base is not flat on the glass, gently use a bench vice to straighten it up as far as you can, and a file it to finish off.


Before all that, keep trying the timing - it often needs to be a bit advanced to get it right, especially with unleaded fuel. Or it may be too advanced already

Title: Funny stop
Post by: Nurudin on July 06, 2006, 10:36:11 PM

I think its the carb now. When I put my other carb in the backfire stops and it does not over run, so I dont think I have the problem with the timing.  The other carb has another problem. The engine stops on idle. I have cleand it with compressed air and everything else I could think of. Ill check the air gap tomorow. I think I have read somewhere that if I spray the base of the carb with WD40 I should see if there are any leaks?

Thanks

Title: Funny stop
Post by: Nurudin on July 06, 2006, 10:42:56 PM

Oh, and I use leaded fuel. We still have it here in Bosnia.