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 Midget and Sprite Technical - Interesting conundrum 2.0

Going back to my original problem, after tightening the screws that hold down the piston chamber it ran fine but then started to miss and cough and eventually quit. After a while it would run fine and then start doing it again. Played with things and found that the jet bearing came loose on the front carb (unscrewed itself) making it run very rich and finally flooding the engine. After much head scratching I found the problem and screwed it back in. Now it runs fine but the carbs are getting on in years since they're from 1968 and have about 100,000 miles on them. I've been considering going with Moss's down draft Weber DGV setup. Since I've got a PCV on mine I'd have to adapt it somehow. Has anyone done this conversion and what is the general opinion on doing this?
Martin

Hi Martin,

before going down the Weber route, have you considered refurbishing your existing SUs with one of these kits?
http://minispares.com/product/classic/CRK101.aspx
Jeremy MkIII

Jeremy,

I've done a refurbishment of the carbs in the past but the problem was with the jet bearing coming loose which isn't included in that kit. After returning it to its proper position it works fine but with the age of the carbs, I don't know how long it will stay that way.

The advantages that I see with going to the Weber are that it's new so no wear and no need to synchronize anything. And it is cheaper than buying new S.U. carbs.
Martin

Aah, didn't appreciate you had done a renovation already Martin and that the worn part is not included in the refurb kit.
Have you read Daniel's book where he writes about Weber & Dellorto down draught and side draught carbs?
Jeremy MkIII

I don't have Daniel's book but years ago I had a Weber 45 DCOE side draft on the engine. It was a bit of a gas guzzler so I went back to the S.U. setup since I don't compete with the car. Just a strong daily driver that can keep up with motorway traffic. The thing that I like about the down draft is that it is close to a direct replacement.
Martin

Martin---DGV, good little carb. It's a completely different carb to a DCOE side draught
Heaps of cars running them here, they were std. on GT Cortinas and even the 6cyl Ford Falcons 80 thru 86 ran them, much more economical than the old Strombergs they had previously. 1600Formula Ford racers have them
You could even go all modern and have a DGEV with an electric choke--that'd be a bit flash
The only down side with them is that the fuel has to be super clean, so you'll need a good fuel filter
The idle jet and the progression jet for the secondry side are tiny and prone to catching any rubbish at all that might be in the fuel---

willy
William Revit

Willy,

Good to hear that they are a reliable carb. Right now I'll wait to see if my S.U. readjusts itself again. I don't understand how the jet bearing unscrewed itself. I'll have to take a closer look at it and see if the spring that holds it firmly is broken since I could turn it with my fingers.
Martin

This thread was discussed between 18/06/2022 and 20/06/2022

MG Midget and Sprite Technical index

This thread is from the archives. Join the live MG Midget and Sprite Technical BBS now