MG-Cars.info

Welcome to our Site for MG, Triumph and Austin-Healey Car Information.

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 TD TF 1500 - TD Dripping Jet

So on to the next issue. While replacing the melted choke cable from the last disaster I have discovered that the jet on the rear carb is seeping fuel. Not a lot right now but I'm sure it will only get worse and lead to a fire hazard.

I haven't taken anything apart yet so I have no idea of the condition of the jets or needles but why would these leak? Bad cork sealing ring or gland washer or maybe both? Or neither?

First pic is the rear jet.

S Grimm

Front carb.



S Grimm

Exploded view for your reference pilfered from 'The T Series Handbook' golden anniversary edition. Apologize for the sideways pic. My iPhone hates me!

Stuart

S Grimm

Try tightening the Jet Locking Screw a tiny amount - - about a quarter of a flat (1/24th turn). Let it sit for a day. If it still leaks, then maybe try another quarter-flat. If that doesn't stop the drip, then it could be the glands or the cork sealing ring as you noted. I would suggest buying an SU Master Rebuilt Kit and replace the cork and other parts.

This video by Lawrie Alexander is excellant. He disassembles, rebuilds, tunes all major SU carbs.
https://mossmotors.com/mgb/books-videos/repair-videos/video-su-rebuild-dvd

Even after rebuilding, the H-4 carbs on my TF still dripped. I replaced the cork glands and washers with O-rings. No more drips. Some people like O-rings. Some don't.

Info on my Google Drive ...
https://drive.google.com/file/d/0BxisXBEpc-IWeXFOQzZZQnNScFk/view?usp=sharing

Lonnie
TF7211
LM Cook

Stuart - please contact me off-line.

Tom Lange
MGT Repair

tlange@acadia.net
t lange

After a few emails with Tom I decided to have the bodies rebushed and new shafts fitted. I don't think that they were too bad but it's difficult to tell with the throttle return spring attached. I couldn't get the retainer off without buggering up the screws so I left them on. Sent them out to Joe Curto to get done. He can deal with the recalcitrant screws!

Anyway was looking at the parts I have left over and noticed that the dashpot springs are different lengths. One is just under 5" and the other is around 4.75". Neither has any colour left. Looking at the Moss catalogue there doesn't seem to be a spring listed for the TD. Other forums have suggested that no spring was fitted. Others say no spring on brass pistons or ones with weights fitted.

Opinions?

Here's some pics of the parts.


S Grimm

#2



S Grimm

#3



S Grimm

#4



S Grimm

Last one. By the way the pistons feel quite heavy compared to the ones from my MGB that I had ages ago. But my memory is awfully faulty.



S Grimm

To my knowledge, if their aluminum they require springs, if their brass they don't. PJ
PJ Jennings

Those very clearly have weights on the pistons, so should not need springs.
Lew Palmer

I solved al my dripping jets by fitting Teflon O rings from Mr. Tom Bryant up in Maine.
That was 8+ years ago and so far no issues. I am sure if the carb parts are not worn or dirty, the originals cork and graphite ones will work also. But these new materials are good.


Rod Jones

Tom Bryant
32 JBS Way
Wiscasset, Maine 04578
207-443-6338

If you wanted to give it a try.
Rod
Rod Jones

6 or 7 years ago I got a Moss kit with cork seals and installed to cure this rear carb leak. Soaked the cork etc. Installed and the rear carb still leaked. I pulled the carb and reversed the cork seal. No leaks since then.
It does amaze me that a cork seal on a live shaft can actually seal for all these years.
Peter Dahlquist

This thread was discussed between 15/09/2019 and 02/10/2019

MG TD TF 1500 index

This thread is from the archives. Join the live MG TD TF 1500 BBS now