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MG TD TF 1500 - TD starting problems (part 2)

a couple weeks ago I posted on the problems I was having getting my dad's 53 TD started. I was going to reply to the same thread, but it seems to be archived. anyway, lots of people had good suggestions, so I'll recount what's happened so far:

the car has been sitting for at least 3 years w/o running. at first I thought it was an ignition problem. someone suggested there was a kill switch - I did find a kill switch, but it was already on. I have +12V to the coil. i pulled the plugs and had no spark. i cleaned them up, cranked the starter and got spark on each one. put the plugs back in, still not starting. someone else suggested bad gas, so I added some fresh to what was already in the tank. after running the starter a bit, I got some chugs, and finally a it sputtered around for about 30 seconds and died. no nothing after that until the battery was dead.

next, I drained out all the gas that was in the tank, and put about a gallon of fresh gas in it (with lead substitute). run the starter awhile, still nothing. then it occured to me that I hadn't been hearing as much clicking out of the fuel pump as I had been. so i pulled the fuel line from the pump to the carbs, and it was bone dry. i unhooked the line from the tank to the pump, and it, too, was dry. i pulled the pump completely out of the car, and hooked it up to a good +12 and ground, and it clicks once every 5 seconds or so. doesn't seem right to me.

thoughts?

is the fuel pump serviceable, or do I need a replacement?

in retrospect, it seems the car had at least 3 problems at the same time: plugs fouled up, bad gas, and bad fuel pump. it's a good thing i'm not in a rush to get this thing going. :)
dave thieben

dave, there will be a lot sharper guys than me respond here, but since they all must have jobs today i will step in until they get home from work. to eliminate the fuel pump as a source of trouble, just diconnect it so it won't run and set up a jury can with fuel. it doesn't have to be a lot, just have it safely elevated to provide some head pressure. you do not need the lead substitute. ever..really, you don't. lead was added years ago as a way to increase octane rating. when it was removed from fuel there was alot of debate about the effects of fuel without lead on an engine's valve seats. it was anecdotal and all field service has shown nil effects. the concern was without the lead there would be valve seat recession. i had a '35 engine that had only been run on leaded fuel its entire service life and it had valve seat recession. field tests support this. valve seat recession is a reflection of service use rather than fuel lead content. if the plugs are clean, deliver a good spark at the proper time, you have compression, you have a source of good fuel the engine will run. i think you are correct in focusing most of your efforts on the fuel supply/fuel mixture issues. (ie. gas and carbs) but also trace through your primary and secondary ignition wiring. did the previous owner change the cars polarity? this will cause a need to change the coil/distributor wiring. many people forget this. (the engine still will spark, just not as hot) the smart guys will be along in a bit. i better get back to the honey do list. regards, tom
tm peterson

It sounds like your fuel line may be clogged, Unhook the line to the pump and blow a burst of compressed air into the fill hole. If there is no gas, you'll need to remove the gas line and replace it or try to clear it. Acetone will usually remove most of the gunk.
Russ Oakley

thanks for the ideas tom. i hadn't thought of just supplying gas with a can. i'll try that next.

it is still a positive ground elec system.

that's good to know about the lead. makes it easier on me. ;)
dave thieben

These fuel pumps are temperamental, especially after setting awhile. Before replacing the pump, try cleaning the points. The points can also be adjusted, but hold off that for awhile. The black plastic cap on the end of the pump will come off. The pump probably has a band of electrical tape around the seam, and you have to remove a nut, which is under the knurled one that was holding the electrical wire. With the cap off, you will see a set of electrical contacts. Carefully clean these with preferable some fine (400 grit) body sanding wet/dry paper, or maybe a fine emery board, file, etc. Do not bend them. If you have some electronic contact spray, give them a shot. Replace the pump and try it. You may have to give the body of the pump a couple of good taps with a screwdriver handle to get it started. It should click steadily until the fuel float bowls on the sides of the carbs are full. Watch that they don’t overflow and continue to pump fuel on the floor. If fuel comes out of one of the overflow pipes, this means the float needle valve is stuck- also a problem due to storage and evaporated gas. A good rap on the side of the float bowl will generally cause the float valve to work. If you had the engine firing before, a steady supply of fresh fuel should do it.
These engines also have a manual choke for initial starting. The choke knob should be fully back for start up, and then decreased to smooth out the engine and keep it running. Continue to decrease it periodically until the engine is warmed up – about 3-or 5 minutes.

Dallas
Dallas Congleton

Dave,

You're right, with no pressure at the fuel pump outlet, the pump should "click" a couple times/second, rather than once in five seconds.

If you can eliminate the points as the problem by cleaning them as suggested and the problem persists, it could be that the outlet valve setup is plugged up, or possibly the diaphragm inside the pump is just all gummed up. If so, the people here online can talk you through those problems, too.

Anyway, as you can tell, these fuel pumps are very serviceable.

Cheers,
Greg
Greg Van Hook

Dave

Sounds to me that the fuel screen in the tank is plugged. You can blow air through it, but if there is gunk on the bottom of the tank, it will just plug up again.

Unhook the fuel line at the tank and then take out the filter unit. The nut that is against the tank (where the fule line hools up) unscrews. The screen is brass. Clean it well, then rinse the tank out really well. There are baffles in the tank, so getting a good sloshing will require some bouncing on the back of the car.
Bruce Cunha

ok... got some updates. i dribbled some gas down the line from the pump to the carbs, pulled on the starter, and it fired right up for about 15-20 secs. so, the problem is from there back.

i cleaned the contacts on the fuel pump with some sandpaper, but that didn't seem to help much. it still clicks very slowly. i did notice that as I removed the line from the tank from the pump, it started to click a little faster. almost as if there is too much strain to pull the gas through.

i blew air into the tank and I got gas up by the pump, so at least some gas is getting up to it.

also, I left the key on for a couple minutes while I fiddled around, and I noticed the pump body became VERY hot.

what's next? what can I do to get this thing working better?

thanks for all your help so far, guys. i'll try and get pictures posted up so you can see what i'm working on. :)

dave
dave thieben

Dave - You can find fuel delivery troubleshooting guide that I wrote some time ago at: http://www.custompistols.com/cars/dave/ddFuelDeliveryTroubleshooting.htm
This will give you a step by step method of troubleshooting fuel delvery problems. That said, I am with Greg, a pump that is runing on a battery with no fuel line hooked up to either ilet or outlet side of he pump should be clicking away as several clicks a second. You may have old gummy gas in the pump, the diaphragm may have hardened, the valves may be stuck closed, or the pump coil could just be old and tired. The pump can b rebuilt, parts are available from Moss and Abingdon. Good luck - Dave
David DuBois

Have you pulled the connection at the tank and cleaned out the little brass filter....mine was totally gummed up and wouldn't let any fuel pass at all?
gordon lawson - TD 27667

Clean the tank and everything else, or you'll have recurring problems.
Tom

I am with Tom on this one...think you have a tank full of nastie!
Try taking a "parts magnet" (the one's they sell on extendable shaft at auto stores for a couple of bucks) and stick it all the way down in the tank. If it looks like mine did you will know what you have to do next!
Yes, I DID drop a screw in my tank when re-fitting the cap is why I did this. I had also paid someone to "clean the tank" before it was re-painted. The next thing to "drop" was my jaw!
Nappa sells a little "clear fuel filter" you can put in the line back there! Cheap insurance to keep that crap out of fuel pump & carbs!
Also see the "TF 1500 coil overheats" thread. I really hate to keep slamming the hand that feeds us ...but the re-placement wires from our "usual source" that you have to make from a kit are crap! I had 3 of them on in 1 season. Bite the bullet here and get the "bumble-bee" wire! If you don't believe me make one wire with it and do your own "side-by-side" test for spark with the other!
Cheer's & Best Regards
David 55 TF1500 #7427
David Sheward

ok. i finally got around to posting the update. thanks all for your help so far. I'm getting closer.

i took the pump off and pulled it apart. there was some chunky black stuff in the filter inside it. i cleaned it all up and reassembled. now it chatters away like a 12 year old girl on the phone. great!

however, it's still not getting fuel. so, i unhook the fuel line from the tank and blew it out with compressed air, and cleaned the in-tank filter, and put everything back together. i am confident that the lines from the tank to the filter are clean and flow sufficient fuel. but, it's still not getting fuel!

i thought maybe the lines & pump needed to be primed, so I used some compressed air to pressurize the tank a little, and that worked like a charm. it fires right up and idles perfect. however, after a couple minutes, it runs out of fuel and stops pumping from the tank. what the heck is going on here?


thanks for the thoughts.


dave
dave thieben

The tank probably still has crap in it. You can go through what you just did many times, or clean the tank first. That's what I'm guessing is the root of the problem.
Tom

Dave

With the line from the pump to the carbs off and the key on, do you get a good flow of fuel out of the pump? If not, and you are comfortable that the fuel line is not gunked up I would feel that either the pump is actually not pumping, or you have a layer of gunk in the bottom of the tank that is obstructing the tank. Blowing up through the line may only be temporarily unclogging it.

When you took out the tank screen, did you rinse out the tank. Rock the car so it sloshes around and drain it to see if there is sediment in the bottom of the tank.
Bruce Cunha

Dave - Set a can of gas by the car on the side that the pump is on and run a hose from it to the pump (make sure that you have a god connection at the pump so it doesn't leak air). Now turn the ignition on and see if the pump will pull the gas from the can and pump it into the carburetors. If it does and the car will run with that hookup, then your problem is in the tank (clogged filter) or in the fuel line (look to see if the previous owner put an in line filter in the line from the tank to the pump - if so, replace it, or better yet, get rid of it). If the pump doesn't pull gas from the can, then the problem is your pump. There are a number of people who can rebuild your pump for you, including Greg and I. I will suggest that you send the pump to Greg if you want it done this summer as I am up to my eyeballs in home projects this summer. The fact that you said earlier that the pump got hot whe you left the ignition on indicates that you have a bad pump or a clog between the tank and the pump which is causing hte pump to stall in a current on condition. Left on to long in this condition will burn ut the swamping resistor inside the coil housing and eliminate what little arc suppression that the low pressure pumps have. Good luck - Dave
David DuBois

Dave,
"chatters away like a 12 year old girl on the phone"....if that is a very fast loud chatter, sounds like line is still plugged!
Sounds like "gunk in the trunk" to me!
I have the same going on right now in my TF. (I have paid 2 people to clean the tank now!)
I have a clear fuel filter fitted in the line just past my pump to monitor this. Sure enough, last time I went to take the car out, have the exact same problem you are describing. Looking at my filter, it is clogged with "gook" again!
My car is parked at my daughters right now so I still have to go back with tools and a jack stand to change the filter...(just happen to have the replacement sitting here on my desk, (Napa 23002) I like this one because you can see whats going on!

I have a feeling this might have something to do with mixing fuels! I normally run Shell or Citgo Hi-test. Last time I filled tank was with BP. Anybody else out there have any problems when mixxing their "winter blend" with other fuels? Not sure what part of Ohio you are in ...but this might be something you and I have in common!?
I have been emptiing out some gas tanks and plan on getting over to the daughters this week to drain what is in my tank out, fit a fresh filter on the line, and put some fresh gas in. I have not had a parts magnet (like I described earlier) in the tank since last time I had the tank cleaned as I trusted it really got cleaned this time! Visual inspection at my filter has been clean untill last week, so I really feel the clear filter was a good idea!
Keep in touch,
David 55 TF1500 #7427
David Sheward

More:
Just dawned on me ...your no doubt wondering why I need a jack stand to change a filter fitted after the pump! Unlike the TD that has the fuel pump in the bonnet, the TF uses a slightly higher presure pump located above the rear axle...that's where my filter is! I can see it under the car, however....
I'm too damned fat to get under the car enough to change it without jacking it up first! LOL
David
David Sheward

David S. - If your pump is chattering away without pumping fuel, you have an air leak rather than a clog. If there is a clog in the tank or the line from the tank to the pump, the pump will click once and then stall and get hot. If teh clog is between the pump and the carburetors, the pump may not even click once, just do nothing, but not get hot. Chers - Dave D.
David DuBois

i'll try the can of gas right next to the pump. the fuel flow is fine through the line, so I'm confident it's not clogged. i'm guessing the pump has an air leak and isn't effective anymore.

thanks.


dave.t
dave thieben

David D.
Hummmm ...I can "see" it trying to fill my clear filter....but have never heard the pump run as fast as it is now.
Going to try and make it over to daughter garage and figure it out....maybe good thing I keep a spare pump in the car as well!
Cheers,
David 55 TF1500 #7427
David Sheward

This thread was discussed between 13/07/2006 and 27/07/2006

MG TD TF 1500 index

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