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SU fuel pump question

Bayless

Yoda
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I am working on a XK140 that has fuel pump problems. I have done about all the good I can for it so it's about for a professional. First question: Should I have it rebuilt or try to purchase new? Second: If rebuild, who do you recommend? Finally, do you prefer the electronic conversion or leave it with the breakers? Thanks for any advice.
 
I responded in the Spridget forum...

Which pump is this? Single or dual sided?

What is the "symptom" of the failure? No "tick"? Or no fuel with MAD ticking?
 
I HAD an new SU in my MK2.
The PO had just installed it.

The carbs leaked at the fuel inlet.
The filter bowl leaked.
Then the diaphram started leaking at the sides, oozing out.

I gave up, installed a NAPA Facet pump (little black thingie), and guess what?

The carbs quit leaking.
The filter quit giving me the runs.
It's quieter.
And it doesn't leak.

Of course, I do believe the issue might be a pump for multiple Sutter's Unions when I have twin Solexes.

Most of the folks local have given up on SU pumps and gone with something similar to this one.
 
I had the opposite experience when I installed a facet pump in my Healey, it was the low pressure type, but everything leaked and didn't seem to run right after the install, I rebuilt my SU and it was good again. The facet, black plastic case, not the square metal case, maybe not all Facets are created equal. The guy at the auto parts store said many fail after a year or so, my SU ran for about 7 years before bugging out on me, so despite the bad reputation I will still take the SU (and carry the facet I uninstalled as a spare)
 
Funny.
My SU is in a ziploc as a spare.

Did find out Facets need to stay wet.
Loop on inlet and outlet to keep fuel inside the pump when off.

My brand new SU lasted six months, tops.
I do believe the issue on mine is where the rod fits through the rubber diaphram.
I think pressurized fuel is working under the metal washer, down the hole far enough to reach the cord in the diaphram, and it comes out at the edge.
 
Isn't it amazing that so many people complain about the SU pumps, SU carbs and such. I guess they are junk, seeing how they only lasted, mostly maintenance free, for about thirty years. Yup, replace the SU pump with one of those top shelf Chinese made premium pumps! Make sure their "Plug and Play" though, makes them easier to replace and keep a couple spares in the trunk.
Oh well, to each his own.
cool0041.gif
 
Yup, go down and buy a pump that is mass produced and quality control inspected, that statistically will last longer, without constant shoe pounding on it, for less than 1/3 the price of a European pump where quality control died decades ago....
Just need to buy the right pressure and volume pump for your application and install it with good electrical and fuel flow..

Remember when Made in Japan was junk. Not any more they are made better than the junk coming out of Detroit.

And the quality, production increase and cost decrease keeps moving further around the globe
 
An ancilliary to this:

Do any of you really think the latest SU pumps are of the same quality as those installed originally on your vehicle?

That was a question.

Next question:

With the crap they keep adding to our fuels, some of which eats up rubber bits unbeliveably fast, do you think a more modern component that may be better suited to resisting the fuel issues of today might be a better idea?
 
The newer kits are made for the fuels of today. Just keep the alcohol to the minimum. There are new kits which are now electronic and are quite reliable. Available at the specialists and are a little more expensive, but last longer. If your pump or pumps are upgraded, redo the gaskets in the carbs so they too are compatible.
 
Check the pump cast housings for stamps. They used to be dated with a stamp and some with a sticker, which do last quite a while. I assume you are careful about the type of fuel you use and keep your systems clean to have excellent longivity of your pumps.
 
no Larry, not really. I use Shell or BP or Mobil 87 octane which I was told I could get away with since the engine compression is 9:1. I have used 93 octane and have noticed no diference except less money in my debit card. I do not add any additives except half a bottle of Marvel Mystery Oil to each tank about 5 years ago, it seemed to clean the system and lubed the pumps? (again, at the recommendation of a Jaguar mechanic).

Otherwise the pumps are just as they came when I bought the car. Maybe the fact that there are two, makes them last longer? Knock on wood! I will check for stickers or stamps to see if there's any info. Thanks.

Ex
 
To my mind and experience the SU pumps are just fine. There was a rash of plastic counterfeit ones a decade ago or so, New Zealand mfg. IIRC. They weren't too good.

For a replacement, there's a Carter "lift pump" I've used with fine results. P60504 part number. In-line, feeds the two 40 DCOE Webers on the Alfa now, too. Not noisy, pressure is 3~4 PSI and volume is fine for dual or triple SU setups.
 
well I finally got to exploring one of the SU pumps in my S type today.

And what do I find?

A "BMC Factory Approved Rebuilt" pump. I tried to get the picture to show the BMC sticker but nooo, it doesn't want to be photographed.

BMC is/was British Motors Corporation, correct?

I also noticed it was leaking!! so I removed the whole thing and tightened all the screws and banjo fittings. No more leaks.
(this may have been the result of the car sitting for 1 whole year with little gasoline in the tanks).

No dates anywhere, no pun intended.

Ex
 
So, one wonders, how many folks out there who claim to have 40 years on the "original" pump, may have a replacement?
The thot plickens!
 
Ex's pump was likely replaced at a dealership. Great news that th' leak was stemmed with a bit o' torque, too!
 
I gave in and got one of the electronic pumps about two years ago. Has performed great so far. I have the original ready as backup.

Marv
 
PM or e-mail Dave DuBois here onna Forum. He'll have the right info for ya, Ex.

Can you tell where the leak is occurring on the pump? If it's at the diaphragm joint for sure, you may be seeing the effect of alcohol/ethanol fuel 'additive'. The stuff is unkind to older rubber bits.

BMC ceased to exist in about 1967~8... "BLMC" is what it became. Most dealers had stock on their shelves, so may be hard to pin down just when that pump went in.
 
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