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 - Carb Repair Choices

My neighbor and I have done all we can to get my '53 TD back up and running right after a year long layoff. First we discovered the fuel was probably bad, and the tank was drained. Next we checked all the fuel filters, and cleaned the pistons and inside the carb bodies as best we could. Next we clocked the distributor, so I could get the cap off, replaced the plugs, rotor and cap (I have a Petronix), re-did the timing per Jeff Schlemmer's figures, and re-synced the air flow of the carbs. The car was now running quite well and starts instantly. But at idle below 1000, a tad lumpy.

Next came the mixture adjustment. We were able to get the rear carb adjusted (slight rise and then fall back), but no such luck with the front carb. We sprayed the throttle linkage close to each carb body with carb cleaner and discovered an air leak at the front carb, as the engine would bog down heavily when sprayed. So, looks like I have several choices:

1. Replace the bushes of the front carb linkage.

2. Replace the front carb linkage and bushes.

3. As the carbs are likely coated internally with the stuff we cleaned off of what we could see, have the carbs completely cleaned and rebuilt to include linkages and bushes.

I'd like ideas as the best course of action, and if someone could tell how the throttle linkage bushes are mounted I'd appreciate it.
L Karpman

I would seriously consider replacing the throttle shaft. Many times it is only the shaft that is heavily worn. If that is not the case then oversize shafts are available.
Sandy
ss sanders

Thanks. Sorry for the use of "linkage" when I meant "shaft" Yes, that's an option.
L Karpman

Larry, what about calling Joe Curto in NY to ask how much he would charge to install new shafts? Both carbs have probably seen the same amount of service so it might be just as well to bite the bullet now and get it over with.
Glad to read that you are feeling well enough to tinker with the TD again.
Jim Merz

Thanks Jim. I contacted Joe Curto and it's $125 for new shafts installed. That's an option.

The reason I was leaning towards the rebuild is that the TD has less than 500 miles on it since I bought and installed these "rebuilt" carbs in 2009. If the shafts were worn and not redone on rebuild, I am suspicious of the rest of the rebuild. Also, I am concerned about the build up internally of all the gunk from the bad gas we couldn't see to clean. New shafts would be great, but if the carbs are gunked up internally, then I will still have issues.

Yes, tinkering with the TD is far better than all the dang Dr. visits as one's main activity :-)
L Karpman

Maybe spraying the innards with some brake cleaner including the fuel bowl may do wonders for you. What have you got to lose? It may then save some bucks to spend on new shafts.
Jim Merz

OK Jim. We cleaned the pistons and needles, and the innards of the carb bodies as far as we could see. Did not do the fuel bowls or the jets. As I've never rebuilt a carb before, I'm unsure how to clean the jets.

As far having the carbs completely rebuilt, which includes the shafts and bushings, spending the extra bucks may be worthwhile, as at least I know the carbs have been rebuilt by a well known and respected professional, and should serve me well for many years. That said, I want to make sure I have as much of the gunk out of the system as possible before I gum up another set of carbs. I had a Grose Jet stick again today, after running a few days on fresh fuel and fresh Seafoam. A little disheartening.
L Karpman

Are you positive a worn shaft is the leak? Very common for the carb to manifold gasket to leak as the carb mounting flange can warp. Grab the end of the shaft and vigorously wiggle all around to see if there is any slack or movement, there shouldn't be much at all.
George Butz

George. This AM I sprayed the carb cleaner around the carb to manifold gaskets, and all was well. I carefully aimed the small red tube on the end of the nozzle directly at the point where the shaft enters the front carb, and it stumbled. Leads me to believe I have shaft/bushing issues.
L Karpman

I don't think you could find a better rebuild for SU Carbs than Dave Braun, he did mine and I couldn't be happier...
Bob Dougherty

Larry, it sounds like you are on the right path. I would seriously consider having both carbs done since they have probably seen like miles of use.
Jim Merz

Thanks kindly, Bob!

Yes, it's true, I do re-bush and re-pin throttle shafts.

Warmly,
dave
Dave Braun

ave: I was unaware you did carb rebuilding for others until I saw the posts by you and Bob. Sent you an email.
L Karpman

Well gosh... Here is a picture! These are Magnette H4s, similar to MGA.

Dave Braun

This thread was discussed between 15/09/2014 and 18/09/2014

MG TD TF 1500 index

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