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MG MGB Technical - Changing fuel pump

I am about to upgrade my fuel pump to a solid state one. Do I need to empty the fuel tank before starting on this? What is the best way to get at the fuel pump?
Vince

Vince. The set up varies over the years. With the RB cars you can simply pinch off the rubber hose. I seem to remember doing that with my 68GT also.

Best way to get at the pump is to put the rear of the car up on jack stands and remove the right rear wheel to obtain access. Pumps on the RB car are fed through a rubber grommet into the trunk area. On the 68-74 cars the pump was secured near, or onto, the battery box. As I remember it, I had to pull the battery to get to some of the nuts. But, it has been a number of years since I had to replace the fuel pump on the GT.

There will be a little fuel spillage when the lines are disconnected. A wad of paper towels is a good thing to hold under the lines as they are disconnected.

If your solid state pump is an SU, use new fibre washers on the bango bolts.

Les
Les Bengtson

Vince - If there is much fuel in the tank, it will syphone out when the inlet line is detached from the pump. The best way to avoid this situation is to remove the pipe from the fitting at the right side of the tank, then the only fuel that will spill is that which is in the short run of line to the pump. Likewise the fuel in hte line from the pump to the carbs will spill out when the line is removed fromt he pump, but again, there isn's very much and it can be easily wiped up or caught in an oil drain pan.

Not to contradict Les, but if you are using a new SU all electronic pump, the banjo fittings use fiber washers between the banjo bolt and the fitting, but between the fitting and the pump, a 'O' ring is used. Good luck - Dave
David DuBois

Dave. You do not contridict me, you correct me, something that we do here often. Now, you need to explain, in more depth, the differences between the older pumps (the one you rebuilt is working wonderfully well) and the newer pumps. Did they change the design or what? Is it a problem if I should purchase a new SU "all electronic" pump and use my old banjo fittings?

Please consider this and, when you have fully considered the matter, write up a short tech piece on this and send it to me for inclusion on the website. It sounds like something has changed and people should be aware of it. Your tech articles are one of the more popular on the website which is averaging more than 200 "hits" per day. Much of its value is due to you, Tom Sotomayer and Danny Wong who have allowed me to post your expertise. My thanks to all of you.

Les
Les Bengtson

Les - The short answer is yes, the AZX 1300 series of pumps did get a design change and have a recessed 'O' ring grove in the inlet and outlet ports (at least one of the pumps I did for you are that way and have new 'O' rings included under the red foreign material exclusion plugs. I will do a write up with pictures for your web site. Cheers - Dave
David DuBois

Dave. Many thanks. I have only had to install the one fuel pump at this time, the first one you sent, and have not had to dig through the remaining two as they are in the spare parts locker. The one you refer to is probably the new pump, bad from Moss, which went out in the first couple of weeks of use due to a cracked cap. Do not remember any information from either Burlen, nor from Moss, which indicated that it needed something other than the fiber washers used on the earlier model pumps.

Thus, such information would be of use to me and others. I am currently running a late model fuel pump (new) on my LE using the fiber washers. It does not seem to get as good a gas milage as the other Bs in the family. This may be why. More information would be appreciated.

Les
Les Bengtson

Thanks for the advice. The car is a 1977 mgb roadster with rubber bumpers.

I think I am now in a better position to carry out the job.

Thanks to all who contributed.
Vince

Oh, oh, oh. Gas gushed out of a large hole in the flexible hose from the pump to the outward gas line (the one that goes to the engine). I took off the broken hose, and noticed that the banjo fitting had a recessed face that took an O ring. The new hose has two flat faces. I put a fiber washer between the bolt and the banjo fitting. Tightened and tightened it, but get a little gas leak. Should I use the fiber washer between the banjo fitting and the pump, bnetween both faces of the banjo fitting (thist is, one washer per face), the old O ring between the flat face of the banjo and the pump, etc.

I would greatly appreciate a reply as soon as possible because I would like to use the 1968 B roadster (which I got when she was born) tomorrow night.

Thank you. Jerry
jerry

Hi Jerry,

My BGT has always had 2 copper washers which I,ve annealed (heat them cherry red then drop them in water) when they been out, never had a leak.
Fiber washers seen to be all the go now so fit one each side of the banjo fitting. Steel to steel will never seal.
I would not use the O ring if there is no recess for it.

Cheers Martin
M G F Addington

Jerry - You have mail.
David DuBois

M G F -- will do as you and others have suggested.

David BuBois -- Your msg is "You have mail." Are you referring to the msg from M G F or have you sent me a msg that I am supposed to access in some particular way. I am new to this BBS, and don't have the hang of it yet.

Jerry
jerry19

Jerry - YOur e-mail program has stopped my message to you and I am unable to get the form to work properly. Please add me to your list of "authorized" people to receive mail from to get the answer you are looking for. I can't answer it on this forum as there are pictures involved. Cheers - Dave
David DuBois

David - Sorry, have added your name to my address book. You should have no problem sending me a msg.
Jerry
jerry19

Jerry - It looks like my e-mail went through ok. Let me know if this was the information you were looking for. Cheers - Dave
David DuBois

This thread was discussed between 20/04/2006 and 27/04/2006

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