MG Car Repair/SU Electric Fuel Pump
QUESTION: Barrie, I have a 1953 MGTD. It wouldn't start and because I didn't hear the fuel pump tick I assumed it was that. I took the filter out of the pump and cleaned, ran fine emory paper thru points, took line loose at carb (couldn't really tell if it was pumping but gas came out). Then I realized the choke was stuck so I fixed that (you had previously sent me instructions and both carbs were stuck). After doing these things, I pulled out the choke and the car started but after running a couple of seconds it cut off. I think it may have cut off after it had used all the gas in the carb. Now it won't start!!!! The fuel pump is ticking now so I assume it is working. Any thoughts on what I should try. Thanks, Sandy
ANSWER: Hi Sandy. When you turn the ignition key to the ON position - before you hit the starter - you should be able to hear the pump tick until it has filled the two carb float chambers. The pump should eventually slow down and stop.
I always wait until the pump stops ticking before I operate the starter.
If the pump will not stop ticking, then you have a fault. Either the pump is not pumping, or you are out of gas, or one of the float chambers is flooding.
Please let me know exactly what is happening when you try to start the car.
Also, there is a banjo bolt where the fuel line goes into the float chamber, and if you undo the banjo you will find another fuel filter. That may need cleaning as well. I attach a short extract from the owner's handbook for the TF, which is very similar to the TD.
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As for your original question "what is happening when you try to start the car?" I too would wait until the pump stopped before trying to start. However the pump wasn't a steady ticking but more sporadic (fast,slow,stop,start,etc.). But I would still wait until it stopped. When I pulled the started the motor turns over like normal but nothing happens. I don't smell any gas like it may be flooding.
I cleaned the 2 filters going into floats. Little dirty but definitely not blocked. I thought more gas should have come out of the line when I did that so I disconnected fuel line going to first carb and turned key on. No "ticky." Then I took lead off pump terminal and touched it to the body of pump and it sparked. Then took bakelite cover off and touched lead to terminal and it ticked but stopped. I tried to clean the points again and retried. Sometimes it would tick but generally it wouldn't. Those hints were in the workshop manual. Does that sound like I need a pump? Or do you another suggestion? Thanks, Sandy
ANSWER: Hi Sandy.
It sounds like your fuel pump needs an overhaul.
I would remove the pump from the car, remove the points from the pump, and then polish the points with an oil stone.
If you cannot clean them or they are completely worn out, then you need a new set of points. A set of points for an SU pump only costs about $25, whereas an exchange pump costs about $160.
If you need detailed instructions, just ask.
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QUESTION: Unless you think the pump is just too old (I don't ever remember changing-- so over 30 years old) I am going to try to clean the points. Please send me instructions. How will I know if they are just worn out? Thanks, Sandy
Try removing the upper flexible points from the pump and inspect them carefully. Here is an eBay ad for some points, so you can see what they look like:
The removable points are on the right of the photo. They are held in place by a single small screw. It should be possible to clean and polish the old points, but eventually they wear out and need replacing.
The TD had single points, whereas these eBay ones are double points from an MGB. They are an excellent upgrade for your pump and they will fit straight on.
Let me know how you get on. If you are unsure, send me a photo of your points.