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Facet pump - explanation for superiority over SU

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steveg

steveg

Yoda
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For a long time, both here and on the autox email list, one of the major topics has been fuel pump issues. Have been searching for an exploded drawing (or photos) of the facet pump.

Here is the US patent for the newer round-body design with integral inlet/outlets - the internals are evidently the same as the gold box pumps:
https://www.google.com/patents/US7150606

The basic principle is when the electromagnet is triggered, it pulls the plunger against the spring towards the center of the magnetic field. Triggering is solid-state.
The o-ring (#34) at the left end of the tube not only seals but acts as a shock-absorber for the action of the plunger. No diaphragms are involved. As far as I can tell, the o-rings are the only rubber items in the pump.
Reasons for SU:
1) concours/original
2) cute sounds
Reasons for Facet:
1) reliability
screenshot.710.jpg
 
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I have an "interrupter type" Facet on my Healey, and I guess it's closing in on twenty-five (25?) years old. Drove the car to a doctor's appointment this morning (office gal wanted to see it...) and it's the kind of product you don't have to think about__it just works. It does however, still make the cute sounds, and when starting the engine off from cold, I have to wait and listen to it for 20-30 seconds to fill up three (3) 45 DCOE float bowls before giving it a squirt and crank.

My first experience with an SU pump failing occurred shortly after my first experience with a British sportscar. Coincidence? I think not! I took delivery of a brand new 1973 MGB on the Friday before Labor Day, and though I wouldn't hazard a guess at how many miles the car had, it was before the weather turned cold (if you know SE Michigan, it could not have been later than the end of October). Coming home from work, the car coasted to a stop in front of Bowlerama, and eighteen (18) year old me didn't have a clue why. Though well within the warranty period, I called an independence mechanic (who drove a '71 MGB, and was my direct influence to buy one myself) and he asked if I could hear the fuel pump...

I hung up the payphone at the bowling alley, walked back across the street, and as instructed, gave a good thump with my fist to the heel-board behind the passenger's seat (with the key on) and heard the pump revive itself. Several more stall-outs and reprimanding thumps, and the car was back to Bob Owen's British Car dealership on Ford Rd for a warranty replacement of the nearly new OE SU fuel pump. I only kept the car another 1-1/2 years, and I don't remember having to replace the 2nd SU pump, but that doesn't mean I didn't__and they probably only cost about $28.00 back then too!.
 
But Randy, if you had fallen for Steve's rational analysis all those years ago and had a boring Facet pump on your MGB, you would not have been part of the shared experience of British car ownership--a failed SU pump. You would not have had that story to tell. Reliability seems overrated!
 
CLEAH said:
But Randy, if you had fallen for Steve's rational analysis all those years ago and had a boring Facet pump on your MGB, you would not have been part of the shared experience of British car ownership--a failed SU pump. You would not have had that story to tell. Reliability seems overrated!
Click to expand...

Ask any Porsche 356 owner if reliability is overrated. :smile:

PS - other peoples' lack-of-reliability stories are much more entertaining than one's own!
 
CLEAH said:
But Randy, if you had fallen for Steve's rational analysis all those years ago and had a boring Facet pump on your MGB, you would not have been part of the shared experience of British car ownership--a failed SU pump. You would not have had that story to tell. Reliability seems overrated!
Click to expand...

Well:
I have had no lack of reliability from the Electronic SU Pumps.
However,I agree with your comment.---:encouragement:

N besides what other pump is going to revive itself if you just give it a thump.:highly_amused:
 
Reminds me of the overused cliche' in that you don't have to be crazy to own a British sportscar, but it sure helps :cheers:
 
I love this little Italian very reliable pump it was on my Healey -serial mounting with the Original SU-
(later substituted by a cylindrical Silver FACET in prevision of 3x45DCOE WEBER fuel drinking)
https://photos.google.com/album/AF1.../AF1QipP6tS3DsKkjFjM1kdbG9b8RozGV3LJ_EmGnSBO1
Exaggerated Fuel FILTER was mounted due the oldest fuel tank rust debris -now eliminated with a new fuel tank

On my MG TD I have one recent SU pump (NO problem in 9 years) but square FACET is in the spare box, ready if problems occur
ATTENTION I see somewhere a Chinese copy of it !!
I warmly recommended the FACET serial assembly, if you want return to home garage.
 
When I was a kid back in the early fifties I remember my mum and many of her friends hitting SU pumps with big Spanners. So I've had seventy years of almost unbroken reliabilty issues with Them.
 
EV2239 said:
When I was a kid back in the early fifties I remember my mum and many of her friends hitting SU pumps with big Spanners. So I've had seventy years of almost unbroken reliabilty issues with Them.
Click to expand...
I remember my friend combat to a MG TF with a big hammer on the hands, lying down at the rear of the car, perfect ,with tweed jacket and bow tie
finally we pushed the car on the uphill (300m) to the mechanic( This is the reason of my fall in love for FACET)
Why MG changed the fuel pump site ?? near the rear axle???
 
steveg said:
I'd argue this pump should be viewed as less reliable than the SU transistorized version simply because it's an unknown quantity...
Click to expand...

But it's German :wink-new:

FWIW, I haven't had any SU pump fail due to failure of the diaphragm--I've owned about 6 of them--although I think they do get stiff over time and probably overtax the switching mechanism.
 
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