Fuel Problem

[GDM100]

Wondered if any one would be kind enough to help me out- I have a J Reg Maestro which has been really reliable since buying it four years ago. Driving it a couple of nights ago the engine cut out. I was able to restart it but immediately cut out again. On checking we found that petrol was pouring out from an overflow pipe at the bottom of the engine which led back to the top part of the carburetor. Someone had a look at it for me and removed the top part of the carburetor which seems ok. Any advice so that i can get it back on the road would be greatly appreciated. If it helps its a manual choke version. (Many thanks to Rebecca and her partner for putting me in touch) Thanks Lyndsey.

[Wetfish]

I might be wrong but it sounds to me as if the carb. is flooding which is causing the engine to over fuel. The carb has a float chamber which controls the amount of fuel going into the carb, the float height is the critical component. All it needs is a bit of grit against the float valve to keep the fuel flowing and hence flooding. I would get the carb off and clean the inside, preferably with a airline as well to make sure. You’ll need new gaskets for the carb otherwise you’ll have more problems when you put it back together.
I had something similar on my MGB which has twin SU’s, stripped it down and found a tiny nit of grit stopping the valve closing causing two cylinders to flood, easy to identify as the plugs were wet with fuel.
I’m assuming here that your Maestro has a SU carb of course.
HTH

[E_T_V]

Yes I'd agree with that. It sounds like the float valve isn't working properly and so it is causing the carb to overfil with fuel.

If you remove the carb and remove the float and needle assembly and give it a good clean out then that may well do the trick.

[Austin-Rover]

I have had the float inside a carburettor puncture in the past, caused by crud from the tank entering the carburettor. Once you have your car fixed, I would suggest installing a fuel filter in the fuel pipe before it enters the carburettor. This will stop a lot of debris from your tank entering the carburettor and causing similar problems.

[G Force]

Hi I would recomend rather than cleaning the needle and seat assembly you fit a new one and reset the float hight. The needle part of the valve will have worn badly where it contacts the seat, also check that there is no petrol in the float as this would indicate a punctured float.

To set the float hight turn the carb upside down and place a straight edge across the body of the carb and the lowest part of the dip in the float. There should be a clearance of 1mm between the lowest part of the dip in the float and the straight edge. if not bend the brass tang on the float to obtain the correct clearance.

Cheers Gary:)

[B18 GPC]

Stikki Floats.

Open up the carb , Spray in come "cleaner" and refit. ;)

[E_T_V]

You've never actually done the job have you? Just spraying cleaner in will do very little if anything. You need to check the float isn't punctured, remove the float valve and clean it at the very least or perhaps even renew it. Then clean out any filter gauzes and give all the jets a blow through and then a wash with alcohol to remove any water traces.

[GDM100]

Thankyou for all the suggestions- Ill give them a go, and hopefully will be able to sort it!!!! :)