Leaking carb.

[JOWETTJAVELIN]

What ho. There is a leak on the carb of my Series II Minor (original, completely standard engine and carb). Fuel economy is 29 mpg - a very poor figure for an 803!! My mechanic says it is the choke but I thought S.U's didn't have a choke as such? Anyway it seems to be leaking from something connected to the float chamber, just forward of the main jet. There was a nut on it which I checked for tightness but it's still leaking.

P.S. It was also running too rich so I adjusted the jet upwards a few turns at a time as per the manual, but this has had no impact on fuel economy either. Could there be a connection?

Any ideas?
I will upload some photos soon to give you a better picture...

[mike.perry]

The SU carb does not have a choke as such, it has a mixture enrichment devise whereby the jet is lowered to supply more fuel past the needle for cold running. It is however normally referred to as the choke and the operating knob is identified by a C
The main sources of leaks on an H1/H2 carb are from the joint between the float chamber and the carb. If there is still a fuel leak after tightening the bolt then the seals will need replacing.
Fuel can also leak from around the jet which again will require new seals
Fuel can overflow from the float chamber if the float is not set at the correct height
New seal kits are available from Burlen Fuels

[JOWETTJAVELIN]

Finally got hold of a gasket kit and took the carb off to examine and renew seals.[frame][/frame]

Leaking petrol effect on underseal/chassis paint.[frame][/frame]

The culprit....[frame][/frame]

Dismantling a H1 carb:[frame][/frame]

soaking cork gaskets in engine oil for 24hrs prior to fitting:[frame][/frame]

not bad for a first-time carb stripper eh?

[bmcecosse]

The seals for the H1 carb are always a bit of a nightmare - cork and concave washers as I remember. Need to be pinched up just enough not to leak - but not so much they trap the jet so it can't move when you pull the 'choke'.....

[JOWETTJAVELIN]

I'm going to leave the little jet 'o' rings alone. Repeated pulling of the choke as far as it would go produced no leaks, so it looks as if it's just that larger cork ring, which as you can see has well and truly had it.

I really don't want to dismantle the choke assembly unless I have to, but have taken the precaution of soaking the rings just in case, as knowing my luck these will go as soon as I replace the carb.

I'll keep you posted on this as I'm going to reassemble it all Sunday afternoon (if I can remember how it all goes back together!)

[beavan]

Hi there.

1955 Series 2, 803cc, H Carb.

Hopefully you can help. Last year I gave my carb a strip down and replaced all Washers etc. Ive noticed over the past couple of months of so that fuel has been leaking very slowly, As fast as I can see it is coming from around the jet locking nut/jet adjusting nut and running down the jet adjusting lever.

Should I be looking at replacing all the washers again / soaking the cork washer again for 24hrs? Or could it be something else that has worn?

I’m a novice at this and I took about 2 days to strip and clean the carb last time.

Ill try and add a photo or two