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MG TD TF 1500 - Gas tank sending unit

Hi guys: I have had the gas tank sending unit, of my TD, freeze twice. The axle that rotates with the floater, and makes the contacts complete the circuit, just freezes and the sending unit stops working. The first time this happened I just ordered a new sending unit, but this time I wish to find out if there is more permanent solution. Has anybody taken apart the sending unit to clean the moving parts? If so, how it is done? Any other suggestions?

Thanks a lot.

Stuart
srmgtd53

Stuart: Not sure how that works, but I would like to know how one tests to see if the unit is working without waiting until the tank is at 2 gals. Is there a meter that is attached to the sending unit to see if the unit works?
Louis
Louis Levin

I have a spare sending unit, that was not working, so I opened it up....It is just a simple moving lever, with a brass contact , that goes up and makes contact, as the float drops....
To make it work, I just bent the brass contact....
Anyway, I put the meter on it, and now it works perfectly....
Very simple device, and easy to diagnose and fix, if you use an Ohm meter.
Edward
E.B. Wesson

Mine was frozen when i first got it...took it apart and cleaned everything...remember adding some grease....worked for 7 years now... when re-installing in tank, tighten each nut a tiny 'tad' and then just keep going round and round till they are all tight...I made a gasket from an auto supply sheet....
gblawson(gordon- TD27667)

I hate to admit it but when I assembled my TD, I put the sending unit in upside down. Now I have the little green light when I have fuel and when it goes out, time to gas up. Hasn't gone out yet but when it does, I'll correct.

Bill
Bill Brown

Hi Guys: I do not think I explained my problem correctly. The problem is that the low gas warning light does not go off, no matter how full the tank is. I removed the sending unit and found out that the axle that holds the float is frozen to the body of the sending unit, not allowing the float to move as the gas is consumed. This is the second time I have had this problem and wondered is there was any DIY solution, short of buying a new sending unit. Any advice will be appreciated. Thank you very much.

Stuart
srmgtd53

Sorry I misunderstood....I would break it loose, check for correct operation with a meter, and lube it with a good grade of water-proof bearing grease, being careful, not to get the grease on the contacts.....
If you can't break it loose, you have no choice but to replace it....
Edward
E.B. Wesson

I used 'Thrust' penetrating oil and a bit of wiggling.....then, as I posted, grease ....
gblawson(gordon- TD27667)

E.B. Why would you want to use a water-proof bearing grease on something which is designed to run submerged in petrol?
G.E. Love

there are several sources for fuel proof grease on the internet. regards, tom
tom peterson

Stuart, if this is the second time it has locked up I would look for the source. Is it just corrosion that is locking up the shaft or something else? If you have lined the tank with some type of sealer it could be breaking down and stopping up the works. It has been reported that alcohol in gas is dissolving some of the gas tank sealant products.

Regards
Rich
Richard Taylor TD3983

Rich may be on to something, especially if you have the evil ethanol-containing gas down there. Definitely open it up and look at the mechanism, and make sure nothing is bent or out of place casuing it to lock. George
George Butz

G.E.
That's what happens when one is in a hurry , and doesn't proof what he writes....So give me 3 lashes with a wet noodle, and 5 demerits....
Frankly, any grease will get it working, and unless the fuel is full of water, the fuel should lubricate it enough...It is made out of petroleum, afterall....
Gas floats on water, so even if there's a little condensation in the tank, that will be at the very bottom, not up where the sender is....
Adding Sta-Bil to the tank , over long periods of non-use, will help a lot.
Edward
E.B. Wesson

Yes, but... Ethanol absorbs moisture and holds it in suspension. This can cause corrosion issues.
D. Sander

That's why I look for gas stations that sell ethanol-free gas....Luckily, there are two in my town.
Edward
E.B. Wesson

This thread was discussed between 27/06/2011 and 30/06/2011

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