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MG TD TF 1500 - Stuck Jet Needle

Here in the Texas summer heat, I rarely drive my TD. I haven't run it for several months due to, well, my fault. Over the past 10 years or so I have had occasional trouble with stuck fuel needles and even with Grose Jets. Today I went to start and drive the TD, and sure enough the rear carb fuel needle was stuck closed(noted by rough running until I tapped the top of the fuel bowl with the butt of a screw driver).

My question is, how common is it for needles to stick after long periods of sitting (a few months), or am I back to replacing needles like I've had to do in the past even when I'd been driving the car regularly? I'm hoping this is a common occurrence when the car has been sitting for a few months.
L Karpman

I find the gas now days goes bad in couple months. This would account for the sticking.
M Grogan

Exact thing happened to me, also rear carb. Had not driven the TD for about 6 weeks. I had to pull the float bowl lid and really fiddle with it to get it unstuck and open. I agree likely the lousy gas, need to switch to non-ethanol completely. George
George Butz

Happened to me as well. Mine was front fuel needle and it kept doing it intermittently - usually very disconcertingly when slowing for a junction.
I cured it by cleaning the seat of the valve with alcohol and a cotton bud.

David
David Wardell

"need to switch to non-ethanol completely. George"

Hi George. Unfortunately in this area of Texas (Dallas/Ft. Worth) EPA summer formulations require ethanol in all gas in the summer months. So I guess this winter I'll find the non-ethanol and "fill 'er up."
L Karpman

I struggle to believe that the alcohol content has got anything to do with it. If its sticking, its because there is something else in there that becomes a sticky residue - the alcohol would just evaporate completely.
Dave H
Dave Hill

Use a bit of SeaFoam or equivalent fuel stabilizer when storing for longer than a month or two. This keeps the fuel from deteriorating and causing needle valves to stick.
And if the Grose jets are not the older ones, do yourself a favor and get some Viton tipped needle valves. The newer Grose jets are notorious for sticking.
Lew3

Nor familiar with the grose jet needles, but standard ones can be polished with good results, as far as sticking. You only need an electric drill and a q-tip and a little bit of metal polish.

As I recall I just needed to detail the q-tip a bit by removing a bit of the cotton on the end before loading it with polish, then take apart the float bowl lid and remove to work on the needle seat in place in the bowl lid. Take out the needle and go to polishing. Maybe tooth paste can be used, also. I forget what the needles look like, do not recall if I polished them, or just the cylindrical opening for the needle. Of concern is residue polish, which turns black from polishing. Use your good sense to rinse it away.

Also make sure when you have the lid back assembled that when the float is allowed to flop down all the way the needle does not become "cocked" as you don't want that valve sticking open. Its been known to happen and is not all so rare.
R Owen

A few decades ago I went through a period of sticking float bowl valves but that was when MTBE was put in the gasoline. I have not had this issue for many years using the 10% ethanol gasoline now sold in the USA.
John Quilter

Larry - Did you use a slushing compound or other type of sealer in your fuel tank when you restored the TD? I ask because I used an aircraft slushing compound to seal the interior of the tank when I restored our TD and about 5 or 6 years ago I had an episode of having the valve disks in the fuel pump become glued to the seats. Cleaned the fuel pump and got it working only to have both of the carburetor needle valves glued shut. I took the tank to an outfit in British Columbia and had them dip strip the tank, followed with dipping the tank in zinc phosphate as an anti rust treatment. I have not had a recurrence of the problem. Cheers - Dave
DW DuBois

Hi Dave. I did not restore the TD. I simply improved it's performance, and appearance, at least in my opinion :-) So, I have no idea what, if anything, was done to the fuel tank. But based on some of the nightmares I found after I bought it, I wouldn't be surprised by anything.
L Karpman

Dave H, Ethanol in fuel dissolves coatings (such as happened to David D above and others) which are left when the fuel evaporates, is hygroscopic (absorbs moisture) which causes corrosion, and is horrible. George
George Butz

George B. Its possible, but I'm not sure there is conclusive evidence. I haven't seen an old car with carbs yet, that didn't have a brown deposit in the float bowls, yet many of those cars never saw fuel containing alcohol. All I'm saying is that kind of thing can happen with any fuel. If I am going to lay up my car for a few weeks or months, I drain the tank, run the carbs dry, and put the fuel in a sealed jerry can. Its better for the car and better for the fuel (no loss of volatiles or admission of water).
Dave H
Dave Hill

Just a note, all Conoco stations here sell 3 grades of non ethanol gas and 1 grade of ethanol, 10%-85 octane. I use only non ethanol 85 in the TF and have no issues. Just sayin. PJ
Paul161

Gents,

Just one more vote for no alcohol. For several years each spring was carb cleaning time. Green goo in the float chamber and stick needle valve. Gross jets that could not be cleaned as the ball would stick in the closed position regardless of carb and brake clean. Now gasoline only and problems are gone.

Regards,

Jim haskins 1953 TD
J M Haskins

Dave D-
Sounds like you got the tank "parkerized" or something similar, with the zinc phosphate dip, inside/outside. What color did it turn the steel? Or was it something quite different from Parkerizing?

For no ethanol gasso in California, it appears to be not allowed, except in cans of 2-stroke premixed for lawnmowers, etc.
D mckellar

Jim, I had two new sets of Gross jets in my carbs and both sets leaked in one jet or the other bypassing the ball, I replaced them with Viton jets and have had no issues since. PJ
Paul161

This thread was discussed between 14/08/2016 and 16/08/2016

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