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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 MGA - Spare fuel pump

Im looking to carry a spare fuel pump just in case, the one i have fitted now is a facet cylinder type fitted by the po and im thinking of getting one of the cube type as a back up but what psi do I need?, i have an 1800b engine and carbs, any ideas please, Vin
Vin Rafter

Vin

I have been running a Facet Blue F5E cylindrical with my 1800 for 12 years. Most reliable. I believe it delivers 6-8 psi.

Where do you stop with carrying spares?

Steve
Steve Gyles

Hi Vin
I would get exactly the same design of fuel pump as you have fitted already assuming that it working ok, if you check the model number on it or the serial number the supplier will confirm if it gives enough fuel flow for the engine.

By doing this you would be sure that the pump would work for your car but more importantly, would be really easy to fit at the roadside in an emergency.
If you are not sure about your present pump, you could always fit a the new one and keep the old one as the spare.
My square facet pump has no problem supplying the carbs even very high revs so I will check to see which model it is and let you know.

I am also looking for some rubber bobbins to use to mount my present facet pump as it is distinctively noisy mounted directly as is is now.

Colyn
( You missed a great run out on sunday Vin, some great roads to drive, and also some really nice people. My first run out with the S Yorks MGCC group but they were great fun to be with. The roads in Doncaster were still damp when I finally decided to take a chance with the weather, but by the time I arrived in Wentworth the roads were dry, the sun was out and we arrived in the Waterways museum in Goole to sit out in the sun. I think I covered about 100 miles and I cant wait for the next one.)
Colyn Firth

4 psi is the maximum that should be used with SU carburetors.

Instead of carrying a spare pump, a better solution is to install it as a permanently installed backup pump. See the article, Backup Fuel Pump in the SU Fuel Pump Articles section of my web site at: http://homepages.donobi.net/sufuelpumps/ Installing a second pump with the power to the two pumps being switched through a single pole, double throw switch, enable one to get home with the flip of a switch, without having to crawl under the car to install the back up pump at the side of the road, a dangerous situation. Cheers- Dave
David DuBois

My Facet pump has been ticking over for at least 15 years. As Steve says where do we stop carrying spares, can't imagine I would need to carry a second one. But then I haven't carried a spare wheel/tyre for 20 years either -- suppose I will suffer a flat now that I mention it!!
Barry
Barry Gannon

I only use 1 12 volt battery, so I have a backup pump mounted on the spare battery bracket. If the pump fails all I have to do is connect the rubber hoses and the wiring I have in place, and I'm ready to go. I found an aftermarket electric pump that outputs 1-3 psi which works great with the SUs.
Mark J Michalak

Barry - The electric fuel pump, regardless of what brand it is, is still an electromechanical device and after 40 years in the electronics trade, if I ever learned anything, it is not to trust the stuff. It can and will fail at any time, for any reason - usually the worst possible and the most capricious reason. After having to change out a pump on our MGB on the shoulder of a freeway (motorway) with traffic streaming past at 70+ MPH, I decided that I would never do that again. I don't even need to pull to the side of the road to change pumps now, just flip a switch. Oh yes, I had a Facet pump fail on a pickup truck we had some years back. Cheers - Dave
David DuBois

Vin

I think you should now have your question answered by David - 4psi max. Your question got me crawling under the car trying to find the model number without success. I have finally found the receipt from nearly 13 years ago. It's a Silver top, pushing out 4-5.5psi. In addition I installed a filter/regulator between the pump and carbs, fitting it on the engine firewall (visible in image below the trunking and behind the heater valve).

Steve


Steve Gyles

Vin
I had my facet pump (square bodied type) stop working the one time about 18 months ago. It didnt respond like the original SU HP pump did, to a tap with a hammer, so I disconnected the output fuel line to it and found that somehow an airlock had occurred.
Once the pump was full of fuel again it was fine and has been ever since.
Not certain why it happened but my guess is that I has a very unreliable fuel gauge at the time and possibly ran low on fuel.

Maybe having a extra fuel pump fitted in parallel with the main one isnt such a bad idea, it would probably have got me going again that day.
Colyn
Colyn Firth

A question/clarification to David please.
You clearly advocate fitting a spare pump ready to operate rather than merely carried as spare, for the good reasons given in your website article. I like the idea and may do the same. Can you clarify - should the second pump be connected in series with the fuel line, rather than in parallel? If so, presumably it can be fitted before or after the original pump? Also, in your experience can any readily available 4psi fuel pump, whether SU, Facet or whichever, happily sit for years in a standby, inoperative state with fuel being pushed through it, in series, by the main operative SU pump? No problems there?
Thanks
Bruce.
Bruce Mayo

Funny thing about redundant and spare parts. If you install a spare part on the car, and it is not used for several years, there is no guarantee that it will work when you need it. If you want to assure that it will work when needed it should be exercised periodically. If you have dual pumps with a double throw switch you can flip the switch periodically (maybe each time you change the engine oil) to give both pumps some regular exercise.

With check valves inside the pumps they will work when connected either in parallel or in series. If they never run under power at the same time it's okay either way. Two pumps in series running at the same time would double the pressure, which is a real no-no for SU carburetors.

Two pumps in parallel running at the same time can double the available flow volume with no increase of pressure. That is not necessary for a stock engine, but it doesn't hurt anything. So you can plumb two in parallel and also wire them in parallel to run whenever they feel like running, and you don't need a switch. On initial power up they will both run until flow stops and pressure is up. During low flow conditions one may do all of the pumping if it has a slightly higher pressure threshold for switch on. For pumps that run all of the time they can both run continuously with no harm, and if one craps out you would never notice it (until the second one also craps out). In that case is may pay to check occasionally that both will actually run with initial switch on (and replace one if it doesn't).

That last issue brings up another interesting point about reliability. Introducing more parts to the system actually increases the probability of a failure in any given period of time. You need to pay close attention the the consequences of a possible failure.

Installing dual fuel pumps increases initial cost of parts and labor. It will ultimately also increase long term maintenance (changing hoses occasionally for instance). But all of that increase of cost and inconvenience may be offset by a certain peace of mind, and a possible once in a lifetime savings of cost and inconvenience if it might circumvent a roadside failure.

For the past 20 years (over 200,000 miles in my MGA) I have been using a (cheap) aftermarket electronic fuel pump. Since they commonly run over 100,000 miles with no problem it seems more appropriate to carry a spare for a long trip, and prepare it for a quick change. Pinch type hose clamps, plug-in electrical connector, and single pinch bolt mounting may make changing the fuel pump a 5-minute job, even on the roadside. See here: http://mgaguru.com/mgtech/fuel/fp201.htm

For long term reliability, least cost and least long term maintenance, I prefer to keep the car simple with no extra hoses, fittings, wiring or double pump mountings. I do understand the logic behind flipping a switch in traffic to bypass a failed fuel pump. Each to his own, but a certain amount of preventative maintenance might avoid that problem without the need for redundancy. Since using this type of fuel pump I have never been stranded due to a fuel pump failure.

$.02
Barney Gaylord

Thanks Barney. Your usual exhaustive and comprehensive contribution with lots to think about. Back to the drawing board!
Bruce.
Bruce Mayo

"If you install a spare part on the car, and it is not used for several years, there is no guarantee that it will work when you need it."

This is especially true if the backup or spare is a points style SU or Harting pump, but not so much if it is an all electronic SU pump or one that I have modified to solid state, or one of the after market pumps that are solid state like the Facet or Carter. It is still a good idea (I would suggest mandatory) to check the operation periodically on any spare or permanently installed backup, especially if it is installed as Barney suggests, where the pump is powered all the time. Cheers - Dave
David DuBois

I have a facet style pump mounted on a the battery support frame behind me ( single 12v battery in other frame after ridiculous short life, low power and expense of 6v batteries over the years) and decided some weeks ago to follow direction David lays out in this thread..ie install another in parallel and use a two position throw switch. The new pump in a Fuel Flo 015 ( made in NZ) and it arrived yesterday and looks good quality and it came with good instructions and well packaged. Bought it after reading many blogs...
..one reason for above never did find good support bobbins for the facet so it will be good not to have the machine gun sound behind me. Plenty of room to mount also on the battery frame.
I agree with David's premise about sparing as well...it is normal in process design to spare critical continuous duty mechanical equipment ..especially pumps.
I pulled the old points SU some time ago...an unreliable superceded self destroying design.
Neil Ferguson

Neil, -- The "support bobbins" you need to quiet down your noisy Facet fuel pump:
http://mgaguru.com/mgtech/fuel/fp204.htm
Barney Gaylord

Barney..
I read your site on this subject when I first installed the facet pump and heard the racket( as I do with most issues re my car..many thanks for this wonderful collection of experience and data. It is a goldmine for me )) . I then went walkabout looking for the bobbins here in Oz with no luck( 'isolator mounts' from now on! ..they reminded me of the bobbins that cotton comes on...must stop inventing my own jargon!) . Found them on the web in US but price incl shipping etc was not far off a new pump..ie the Fuel Flo cost me A$78..about US$70 so....made an easy decision ie to have a noisy standby pump.
Fuel Flo looks a very well made robust unit and have been around a long time I understand..
www.fuelflow.co.nz
Neil Ferguson


Hi

I have just installed a Facet silver top pump on my Magnette - does this sort of pump 'tick' all of the time - ie dont cut off?

I am using a filter king regulator at the front of the car - the one with the visible fuel bowl/filter.

Thanks
Gobby
Gobby

The answer to your query, Gobby, is yes, the facet pump never really stops rattling on. It is more noisy when it first starts to prime the float chambers and less so when they are full but it never goes away.
I have been looking for some of the rubber "bobbins" to quieten the pump a little as mentioned above in this thread but not found any yet.

So for now I have resigned myself to listening to the demented "Michael Flatley- Riverdancing" away in his tap shoes inside my fuel pump for the forseeable future.

I suppose the positive side of it is- No Michael Flatley - No MGA driving!

Colyn
Colyn Firth

Guys..I have been scouring the net for these mounts and came across these ..see site below...from a Oz company and have just bought for myself. The company specialises in kit for minis and sells a variety of pumps incl Facets. I am sure there is an equiv. supplier in Blighty .
http://www.minisport.com.au/prod798.htm.
Neil Ferguson


Thanks Guys

I have those mounts (or something very similar - quite soft rubber anyway) on my pump - some improvement but certainly does not stop it :-(

Gobby
Gobby

..and here they are in the UK..at 4.5 pounds..a lot cheaper thanin Oz..look at page 9..
FPA905- FACET RUBBER MOUNT KIT
http://www.fuelsystem.co.uk/web-facet.pdf

Neil Ferguson

Thanks once again Neil, I just couldnt find those rubber mounts whenever I have searched for them over here.

Obviously I was asking for the wrong thing on Google.
I dont know why but "Anti-Michael Flatley noise reduction bobbins" just didnt seem to work!

I have just ordered a mounting kit for my Facet pump and I will let you know what difference they make to the noise when I get them.

Thanks a lot

Colyn
Colyn Firth

This thread was discussed between 27/04/2010 and 04/05/2010

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