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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 - Carbs...1.5?

My source for the MGA 1.5" carbs hasn't got them off and has a set of MGB 1.5's Is there a problem using MGB's instead of the A's?
gblawson(gordon)

Gordon,

The MGB used the HS series of carburetors which have a decidedly different look than the H carbs on the MGA. The Jet Assembly is 'handed' front to rear and consists of a thin transfer tube running from the float bowl to the throttle body. Also, the carbs mount on the bias so you will have to custom make the flanges on your inlet pipe to the engine.

The later HS carbs also have a pop off valve on the butterfly that usually needs to be soldered shut or the throttle disc needs to be replaced with a solid one. Additionally the later carbs have a spring loaded needle that is supposed to prevent misalignement and reduce the jet centering requirement.

But the engine won't care what is doing the mixing and atomizing of fuel... so they will work, just require more modification.

Take a look at the Moss Website for the diagrams.

I haven't the foggiest what to advise you on needles with the HS4...

warmly,
dave
Dave Braun

Not worth the effort Gordon. As Dave says lots of differences, not the least of which is the B carbs require the heat shield ( not a bad thing) for the throttle cable which comes in from the top side. Making a working set up for the T linkage could be done but along with all the other more major obstacles it would be way more than what I would want to attempt.
I'm not sure there will be that much improvement going from the 1 1/4 to 1 1/2 carbs. The 52 I'm working on has rebuilt 1 1/4 but I've got the 1 1/2 set up on the shelf that came off the TF when I put the blower on. Somebody convince me there is value in swaping them out.

LaVerne
LED DOWNEY

Thanks... will mention that and try for the MGA ones... Will try both sets on the car when the head work is done (larger TF valves) and see if I notice any difference....
gblawson(gordon)

gordon, see http://www.ttalk.info/TDMKII.htm for my experience with MGA carburetors for use on a TD. Bud
Bud Krueger

Gordon One of the tricky things about getting MGA carbs to work on a 'T' series is the vacuum takeoff on what was the rear carb on the MGA. It has a 7mm thread. I had a deuce of a time figuring that out. Eventually I found the vacuum pipe from an MGA at an auto jumble. Then it was just a matter of using the caliper and the thread gauge to determine the size of a bolt to plug the hole.

The choke linkages from the 1 1/4" carbs will transfer to the 1 1/2" carbs OK.
Cheers,
Bob
R. K. Jeffers

Problem solved....

The chap who was bringing me the MGA carbs happened to find a pair of mgtf 1.5" carbs in his loft...bought those instead...!!!
gblawson(gordon)

Gordon, if they are TF carbs, & you have a TD, sell them to a TF owner, they are very hard to locate, & shorter than MGA/100-4 carbs. Also GJ needles are too lean, use a # 5 or 6, & get the correct piston springs from Joe Curto.
Len Fanelli

Just got an email from a friend of mine and he has a NOS TF 1.5" manifold plus a rebuild kit...pick them up this morning!



gblawson(gordon)

....and the manifold (along with a rebuild kit/new needles)

gblawson(gordon)

Gordon; Could you post a couple more views of those carbs?(side-rear). Is there a number engraved on the rearward facing side of the main bodies? Curious, Dan
Dan Craig

4031/ is all I can see anywhere on the body of the carbs....both have the same number!
gblawson(gordon)

Look like this? Engraved number is after the slash-difficult to see. Dan

Dan Craig

And they look like this?

Dan Craig

The carbs off my TF are obviously a different breed than those shown.

LED DOWNEY

Also of interest to me is the studs on the rear carb and bolts on the front carb of the manifold. Studs all the way on the one I have.
LED DOWNEY

Dan

I'm reasonably sure you have early Mark II carbs as I have an identical set. Tomorrow I will look at any numbers they may have. Maybe if Joe Curto is following this he could confirm.

Actually I have a third Mk II carb that is mounted on my Shorrock.

Mike Francks
M FRANCKS

I mentioned the studs/bolt issue and was told 'thats how they came'

Also of interest is the colour on the manifold...it is original MG engine red...very maroon with a brown cast. These have been on a shelf for 50 years and I'm assuming this is the original colour.

I will take better photos and post!
gblawson(gordon)

I agree with Mike, those are not TF/MGA carbs. The TF/MGA carbs have four holes in the face as confirmed by the correct Volks air cleaners.

Someone with an early Mark II will have to confirm that the air manifold only had the air intake and two holes for the attaching bolts.

Very interesting.
Bob
R. K. Jeffers

Gordon; Send your friend a good cigar and an extra thank you. Those are indeed TD MKII H4's--haven't seen a set available for sale in years. Most 1 1/2s advertised as being for the MKII are of the design shown in LaVerne's photo which were fitted to TFs and MGAs. Pictures I posted are of my carbs on TD/C 21793. Congratulations on unearthing one of the toughest MKII specific components out there. Wonder if the air cleaner stuff is on his shelf,too? Gonna have to find yourself a buldged right side bonnet section and a set of Andrexs next. Dan
Dan Craig

A few views...

gblawson(gordon)

another

gblawson(gordon)

maybe another? Can't seem to upload more?

gblawson(gordon)

The carb rebuild kit is marked:

(by the seller)
375-258
rebuild kit, carburetor
1 1/2"
TDII
GJ needle

(Moss sticker)
375-258 MG TD KIT - MOSS
2203 GRN 117094


I think the TF had, for some reason, LSP needles?
Anyway, he switched them to the GJ's
gblawson(gordon)

Gordon

My carbs are the same as Dan's.

Front carb is 4031/8, rear is 4031/12 with the 8 and the 12 both being etched on.

Good find.

Mike Francks
M FRANCKS

One of the carbs has a squeezed/soldered copper line...the size of an overflow tube... what would it have been?

gblawson(gordon)

Could have been for a vacum gauge Gordon.
LED DOWNEY

The only reason for a tube connecting there would be for vacuum advance, not a useful place for vac gauge. If it's in an original boss, then the carb body was designed for it, even if it was not normally drilled and tapped on the TDII. If it's not an original boss, but just a drilled hole, I'd say water injection, but then you'd expect both to have it.

Gordon - Since you have the most extraordinary "finder's touch", please get me a young Catherine deNeuve in a Bristol 406 Zagato! Or a Sophia Loren in an Aston Zagato, or...

FRM
FR Millmore

With no provision on the dizzy for an advance Fletch I'm at a loss. Water injection or maybe even upper cylinder lube on only one carb would have me scratching my bald pallatte. Maybe the NO2 port?
LED DOWNEY

Might have been on something with advance oncet, mebbe was a split pair, whodunnit and what dey dun anywho?
(paint fume memories gettin' to me!)

FRM
FR Millmore

Stripped one of them down this morning and cleaned it...re-assembled it and once the other one is done, will take them off for a rebuild!
Looks like I need to find another overflow fitting...

gblawson(gordon)

Gordon, I may have an extra overflow pipe or the fitting in my attic- I'll try to look in the next few days. George
George Butz

Thanks George... I noticed that there was only a float in one of the carbs and no little Y piece, or needle valve... Am seeing the chap who sold them to me tonight and mention it... may have him rebuild them as he does this as well.....
Got the other one cleaned this morning
gblawson(gordon)

The chap rebuilding my carbs decided that I should learn how so I spent the morning with him while he/we worked... I bead blasted all the parts and did assembly with him telling me what to do.... sort of like 'carb school'....
1 down, 1 to go....

gblawson(gordon)

Done...just fine tuning when I put them back on...

gblawson(gordon)

Plays well with others?
LED DOWNEY

Gordon,

Good job on the clean up Gordon, but I suggest that you may have the float bowls reversed. The rim of the bowl should be level with the sides vertical. I'm sure this is something you would have discovered during the instalation. You will enjoy the benefit of this modification in the spring, if you can wait that long.

George Raham
TD 4224
G. L. Raham

Ok...done now...

Think the bowls are on right?

gblawson(gordon)

Nothing like a new dad with his first set of twins.
LED DOWNEY

I don't know Gordon, the front carb looks right but the back carb has a strange set to it. It might be because it is not lined up as it would be on the intake manifold. They look mighty good.

George Raham
G. L. Raham

Possible the nut holding the rear float bowl is not cinched up.
I would use them if he can't.
Sandy
SANDY SANDERS

It isn't uncommon for a float bowl transverse arm to be slightly deformed from years of use. This can contribute to uneven fuel float levels when using the SU method of setting the floats. I've seen several that fractured and were welded back.

warmly,
dave
Dave Braun

Gordon,

One more comment, when you finally get the float bowl set to tighten up, it should be at 90 degrees to the carb body. When the carb is bolted to the manifold and then the head, the rim of the float bowl should be level. Have fun.

George Raham
G. L. Raham

Test fit....(ok...just wanted them sitting on my coffee table)...!!!

gblawson(gordon)

This thread was discussed between 16/10/2009 and 21/11/2009

MG TD TF 1500 index

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