MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG MGA - My H6 Carbs

Can anyone please direct me to a contribution in a thread a few months back from someone who suffered a fuel restriction problem caused by his overtightening the bolt which secures the float chamber to the carb body and so deforming the rubber washer which seals the joint between the two. I hope I have that right, from memory. I think the gist was that the contributor believed that the deformed rubber caused a low flow of fuel to the jet.
Grateful to anyone who can put me on to the piece and how I might be able to recall it from the archive.
Bruce
Bruce Mayo

Hi Bruce
I wrote the contribution -I was having intermitant hesitation at around 3500 revs under load. tried all the usual timing and distributor tuning tricks without success and concluded it must be fuel related checked fuel supply to the carbs all OK- when I tried to tune the carbs I found the front carb was only working part time -took the float chamber off and found the rubber grommets were slightly worn and were causing the fuel pipe to slightly rotate ( i.e. The float chamber connection was not tight enough)occassionally blocking the fuel feed hole to the front carb -since I tempoarily sorted this the hesitation has dissapeared. I will be ordering 4 new rubber washers for both float chambers(part no. AUC1534) when next ordering parts from the MGOC. Barney also advised me that these can cause the problems I was having
Paul
P D Camp

Bruce
The original thread is in the archive under " float chamber alignment" June 26th this year
Paul
P D Camp

Paul. Many thanks. Same symptoms. Same fuel flow checks. Same all ok! I will check the rubber washers.
Bruce
Bruce Mayo

Paul
Don't know any other way to contact a member on this site, so doing it this way! Could we talk? I will be at Goodwood (Revival) tomorrow and (probably) Saturday also. Will you be there? Otherwise I'm on 07802 170135 when you have a minute.
Bruce
Bruce Mayo

I just hopefully fixed a slight fuel leak from the rubber seals on the bottom of the front carb float chamber by tightening up the bolt a little.
I have noticed that the lower of the two seals looks like it has swelled up slightly and I dont like the look of it.

Is there anything I should know about when I replace the seals?

Colyn
Colyn Firth

Bruce
Regretfully I am not attending the Revival ( Family wedding using wedding cars tunbridge wells this weekend) I will give you a ring monday
Paul
P D Camp

Colyn
I have not replaced my seals yet just have realigned mine awaiting the new seals- however when taking the connection apart keep all the parts in order and make sure the concave washer is the right way round ( I put it back wrong and got a leak!!!) It is fairly obvious how it should be reasembled making sure the hole in the banjo lines up with the carb inlet
Mine is the late type connection the earlier type is different and apparently did not use the rubber grommets but I believe th recommendation is to use them now.
The MGOC spares site (under carburetors has a good exploded diagram of all the parts)
Paul
P D Camp

Colyn, just popped a spare set of seals in my tool kit in case you have a failure! The banjo bolt tightens as far as it will go, if I remember rightly. There is a shoulder on the bolt that stops you from over tightening the seals. I got my seals direct from SU
https://www.sucarb.co.uk/ExplodedImageCoordinates.aspx?ProductId=33909&ref=EssentialsDisabled

One cause of leakage on the float bowl union is if the oveflow pipe hits the chassis when the engine moves on its mounts (overflow pipes should be connected to the block by a clip, but sometimes aren't!). This causes the float bowl to move in relation to the carb and either damages the seal permanently or twists it off its seating enough to allow some momentary escape of petrol. I know this because it happened to me!
Lindsay Sampford

Thanks Lyndsay, I have just sent for a set but if I cant fit them in time for the tour I will just have to try harder to keep up with you (and your spares kit)that weekend.

Hope to fit the seals next week, I will pre-dial two 9's on my mobile before I start.
Colyn
Colyn Firth

This thread was discussed between 14/09/2010 and 17/09/2010

MG MGA index

This thread is from the archive. The Live MG MGA BBS is active now.