View Full Version : TR2/3/3A TR3 Mech/Elec Fuel Pump Question

03-17-2009, 09:51 AM
Quick question,

I am going to be using an electric fuel pump (facet/carter etc.) on my TR3 when I start getting it back together. It currently has an electric pump fitted and the mechanical pump orifice in the block covered with a blanking plate.

I was thinking of mounting the electric pump somewhere on the drivers side inner fender close to the stock location of the mechanical pump.

As a back up, I was thinking of removing the blanking plate and fitting a spare mechanical pump that I have, and just plugging the inlet to keep dirt out etc.

If the electric pump was to fail, I was hoping that I might be able to swap the inlet/outlet hoses to the mechanical pump in order to get me home.

Does this sound like a good idea or not?

M. Pied Lourd

03-17-2009, 10:15 AM
Mech pump will be running dry. Not sure if that would be good.
think about mounting 2 electrics side by side with quick electrical disconnect and flex hoses long enough to reach both.


03-17-2009, 10:50 AM

Just run the mechanical pump. No electrical connections. And, in all the years I've driven cars, the mechanical fuel pump has never been the cause of my need to wrench the car by the side of the road.

03-17-2009, 11:07 AM
I have read that, if you're not using the mechanical pump, to remove it, not just disconnect it. Like bgbassplayer says, it will run dry and this is bad for it.

I think this was in Vintage Racing British Sports Cars, but I could very well be wrong.

03-17-2009, 01:54 PM
K Guys,

Thanks for the replies.

M. Pied Lourd

Geo Hahn
03-17-2009, 03:45 PM
...in all the years I've driven cars, the mechanical fuel pump has never been the cause of my need to wrench the car by the side of the road.

Geez, I hope your car doesn't read that.

I have had the mechanical fail twice so I took to carrying a cheap electric for a get-me-home spare and switched to original pumps with priming levers. No problem since, whether due to using original equipment or carrying a good luck charm I couldn't say.

Don Elliott
03-17-2009, 04:38 PM
George - Like Moses, I have never had a problem with my fuel pump, except in 1991 when I stripped the threads in 3 of the holes (too much torque with a huge screwdriver) and I had to get longer screws and put nuts on the bottom. To get me home without any more fuel leaking, I bought 3 tiny "C" clamps for a dollar each and tightened them around the flange joining the upper and lower parts. But never anything serious in 51 years of ownership along the road. Oh yes, about three years ago, I bought a kit and replaced the consumables - just in case.

And of course, I carry a spare mechanical fuel pump with me all the time which guarantees me that the one on the engine will never fail. This is according to the old and true legend that for any spare part you carry in the trunk, the one in operation on the car is guaranteed never to fail.

03-17-2009, 05:32 PM
I have had my pump fail and found that the spare was made with to short of actuator arm. I installed a electric pump by the tank for two reasons. 1 back up pump. 2 stop and fuel vapor blockage during the summer time.


03-17-2009, 06:15 PM
I agree, the stock mechanical pump is very reliable (assuming the diaphragm is compatible with modern fuel). I also carry a spare electric, as a talisman to ensure the mechanical doesn't dare fail :laugh:

But it sounds like Pied is trying to restore to a standard that includes an electric pump so all this isn't very helpful.

Personally, I would still just carry one of the little rectangular Facet pumps as a spare. Easier to press into temporary use, IMO, and possibly useful for other things (like emptying the tank if you need to remove it). And no concerns over the effects of running the pump dry all the time. Also pack a couple of clip leads, some tie wraps, and soft fuel line (which are all good things to have as well). I keep the pump & line in the center of the spare tire, along with the spare distributor (that has also never been needed).

03-19-2009, 06:33 PM
Here's what worked for me on my late 3A:(I wanted my engine compartment to LOOK original)I Took a stock AC fuel pump, removed the two one-way valves; assured that the diaphragm was compatible with modern fuels & routed the fuel thru to keep the diaphragm moist. next I got TWO Facet pumps, a length of aluminum fuel line, an in-line ball **** fuel shutoff, and a generic fuel filter from NAPA.(preferably one with a 90 degree in-to-out.) I made up a bracket to mount the electric pump to the back side of the left hand rear shock. I formed the fuel line from the tank to the shut-off valve, then a short length of the aluminum line, then a length of rubber fuel line to the filter (for easy replacement)then rubber to aluminum to the electric pump, alumnium to rubber to the (shortened) original steel fuel line. Wire the electrics to a switched fused line (A4 at the distributer?) I took the 2nd Facet & set it up to quick-connect at the rubber line just shy of the carbs. That's my road spare, which fits nicely in Randall's favorite storage spot! Sounds like a lot of work but I got it done in less than 4 hours. If you want to really tweek it, make up rubber mounting pads for the electric pump to cut down noise.( Altho I can't hear it with the engine running) Also, an under-dash kill switch is easy to add.