MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

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 - Fuel Pump Backup

I've just gotten a rebuildable SUl fuel pump through EBay and plan to use it as a backup for my TD. I have read earlier threads on the subject, and think I have four options.

1) Club wisdom (FWIW) is to carry an extra fuel pump in the toolbox. Obvious drawback of trying to mount and plumb it on the road.

2) Since others have found that fuel will freely pass through a non-energized SU, I could mount it in-line under the car in front of the fuel tank with a switch to turn on when needed.

3) It could be mounted on the bulkhead and outboard of the original fuel pump a la TD mark II. It could be plumbed in line with the principal fuel pump and energised with an A-B switch.

4) It could be mounted and plumbed exactly as in a Mark II, with both pumps running all the time, and the assumption that one could take over if the other failed.

I have transistorized my main fuel pump, and wasn't planning on doing same to the backup pump

Comments, suggestions, potential problems?

Andy Moyce
52 TD
Andy Moyce

I have installed a second pump a-la-MKII - with the standard brackets and an extra fuel line from the tank - plus some minor electronics with LEDs which allow me to turn on and off either pump, and to see a flash in the corresponding LED when the pump clicks. There is more than one way to do that. I am willing to explain it if someone is interested.

The 4-LED display is in the glove box and the switches just behing the speedometer, for easy access through the hole in the baffleboard.

Denis
Denis L. Baggi

Andy, I just finished the installation of an auxiliary fuel pump per your Option 2. It is identical to the one Moss offers for $79.95 but I bought it from Advance Auto Parts (formerly Parts America, I think) for about $30. It is a low pressure Purolator Pro 42S pump which I mounted on the frame just aft of the rear end of the muffler. I added a three position switch which provides me with two on positions and a center off position. I can select forward pump, aft pump or both off. I made a small bracket for the switch which in turn mounts to the steering column support bracket making it accessible while driving but hidden from view. To keep the original wiring intact, I made a jumper wire from the former fuel pump wire which now feeds power to the switch. Then there is a wire from the switch to the forward or original SU and another from the switch to the aft pump. I tested it for the first time yesterday driving at all normal speeds first using the aft pump, then the original for about 5 miles on each. I also switched while driving at highway speeds with no problems. No more standing by the side of the road at night trying to swap pumps for me!!!!
Try it, you'll like it.
Jim Merz

Jim,

Can you please elaborate on the inline plumbing side of your installation? Did the Purolator pump come with any fittings? Were they flared or compression? Is the fuel line on a TD a standard diameter? Did you have to enlarge/reduce the fittings?

Thanks, Ray
Ray Rockwell

The Purolator was supplied with two metal fittings that adapted the pump to two short segments of rubber hose which were also included. These pieces of hose fit right on to the 5/16"? original fuel line. A piece of the original fuel line has to be removed to accommodate the pump. All I had to additionally buy was four appropriately sized hose clamps.
Jim Merz


The Sacred Octagon carried an article in February about a spare fuel pump for $12.00. Obtain from a lab equipment supplier a #9 stopper (it comes with a small hole in the center)(about $2.00). From you rlocal pharmacy, buy a blood pressure bulb pump (a Marshall #21-125 has a one-way valve inside -- $7.95).

1/4" o.d. copper tubing about 1-1/4" long should be pushed through the stopper. Add a 7' length of drip irrigation 1/4" tubing. To get the tubing over the copper pipe you'll need to heat the tubing with a hair dryer.

A couple of pumps every 10 minutes or so and you can drive forever...
Steve in NJ

I would like to come back to my comment above and I state that I have been running SU pumps for the last 35 years - the setup I describe for the last 10 years driving daily - without any problem. I really fail to see why any other pump would do any better. Actually, one of the monitoring schemes I refer to above (carl Cederstrand's) allows you to activate a pump from the dasboard even when contacts fail.

I am not a purist, but if one has SU pumps, as you do, I fail to see the need for anything else. Andy, if you already have an extra SU pump, then use it and avoid more modern and doubtful products in your wonderful TD.

Denis
Denis L. Baggi

I have been wondering about all the paranoia about a backup fuel pump, do you also have a backup starter motor and generator.Is there some virus that attacks S.U. fuel pumps over there.Is the incidence of failure that high that one must have a backup?
Dave
David Broadbridge

Paranoia?

Just yesterday I was cruising the lovely backroads of North Carolina when suddenly
my TD lost power and I coasted to the side of the road. It would idle but had no power and stalled if put it in gear. I thought "Could it be my ever dependable SU pump?" I swiched over to my Moss inline spare and motored home as fine as could be... Joe "I don't carry a spare starter but do carry a spare tire" Holtslag
Joe Holtslag

When does everyone service the fuel pump? Or is it out of sight out of mind. The owners manual says every 3,000 miles which would be a couple of times a year back in the 50's. Do it every year as part of you rites of spring when you wake the car up after a long winter's nap and clean the points and filters.

Joe

Was your problem a pluged filter in the pump or the fuel line?
Blake J.

This thread was discussed between 12/05/2000 and 27/05/2000

MG TD TF 1500 index

This thread is from the archive. The Live MG TD TF 1500 BBS is active now.