25 replies to this topic

[275 GTB-4]

Hi to all,

I have tried googling for this one without much luck.........can only find high pressure current models

Does anyone have any tech data on the following pump and where I might get gaskets kits etc:

Autopulse made by Walbro Corp
Cass City Mich, USA
Series 2100

I found it on the sub-frame of my Morris Mini 850 project car and was quite surprised. Looks like a well made pump...initially I thought it was off an old aircraft.

[clSD139]

"...initially I thought it was off an old aircraft"

like the beetle engine- porsche designed it 20 years earlier for a plane...

[275 GTB-4]

Originally posted by clSD139
"...initially I thought it was off an old aircraft"

like the beetle engine- porsche designed it 20 years earlier for a plane...

Do tell?? I helped drop and strip one of the 36HP wonders once (why oh why didn't they let them breath a little better... ) but never knew they had an aero lineage. I always thought it was all part of developing a peoples car back in 1936(ish?)

[McGuire]

Originally posted by 275 GTB-4
Hi to all,

I have tried googling for this one without much luck.........can only find high pressure current models

Does anyone have any tech data on the following pump and where I might get gaskets kits etc:

Autopulse made by Walbro Corp
Cass City Mich, USA
Series 2100

I found it on the sub-frame of my Morris Mini 850 project car and was quite surprised. Looks like a well made pump...initially I thought it was off an old aircraft.

Ah yes, the Autopulse fuel pump...those things have been around since the 30s or 40s. (They were used on big trucks and a few cars, Cord I think.) Walbro bought out Autopulse in the 1950's so you have a newer one.

Walbro is still in business so you might try contacting them directly, or try a marine supply house since this pump was very common in pleasure boats.

Electric fuel pumps like to be close to the fuel tank so they can push rather than pull. Where the pump is pulling the fuel is more prone to turn into vapor. The ideal setup is next to the tank and below it.

[McGuire]

Originally posted by 275 GTB-4


Do tell?? I helped drop and strip one of the 36HP wonders once (why oh why didn't they let them breath a little better... ) but never knew they had an aero lineage. I always thought it was all part of developing a peoples car back in 1936(ish?)

As far as I have ever read or heard, the VW engine had no aircraft origins in its backround but was purpose-designed for the Kdf wagen. The "20 years before" story does not make a lot of sense to me as I can't imagine a purpose for a one-liter, four-cylinder aircraft engine in 1913.

That said, very soon after the engine was in production its possibilities for very light aircraft were recognized. (The engine does at least resemble the emergent light aero engine of the period: air-cooled, 4-cylinder opposed, though the Porsche/Kdf was much smaller in displacement.) One of the Horten Bros. WWII flying wing experiments was powered by what became known, after the war, as a "Volkswagen" engine.

If anyone is interested in VW history, there is a tremendous book on the subject by Karl Ludvigsen, Battle for the Beetle.

[CFD Dude]

Is this an electric pump? If it is I'd suggest going to the BMC mechanical one for your 850 unless you're switching to fuel injection. It runs off the cam and they tend to work quite well. We did that with my brother's Mini (1980 Mini Layland 1000, but we switched it to a 1275 Metro Engine) just for convience and it seems to work just fine. Any mini dealer should have lots of the mechanical pumps around.

[Rosemayer]

275 GTB-4


Try this.


www.autoperformanceengineering.com/ html/bel_pump.html

[McGuire]

Originally posted by Rosemayer
275 GTB-4


Try this.


www.autoperformanceengineering.com/ html/bel_pump.html

Hey, good job. I am betting the pump looks a lot like this (foto from the "fuel pumps - bellows" page of the website)



This is the classic Autopulse/Welbro/Dupree fuel pump of myth and legend. The website says they carry repair kits and everything, or you can get a complete new pump for $80 - $100.

I would assume the electric pump was installed because the owner was feeling racy, or was suffering vapor lock problems, or the original mechanical pump failed, or this car once had a larger engine and/or multiple carbs, as the OE pump on BMC cars sometimes had trouble keeping all the chamber pots filled, especially under accel & cornering etc.

[BRIAN GLOVER]

If my memory serves me well, I believe Porsche stole the beetle idea including the air-cooled flat 4 engine from this man of Tatra cars..

Originally posted by McGuire



If anyone is interested in VW history, there is a tremendous book on the subject by Karl Ludvigsen, Battle for the Beetle.

[desmo]

Old school karters will recognize Walbro as the maker of a nice crankcase vacuum powered fuel pump that doubled as a carburetor.

[McGuire]

Originally posted by BRIAN GLOVER
If my memory serves me well, I believe Porsche stole the beetle idea including the air-cooled flat 4 engine from this man of Tatra cars..

A frequent accusation (that Ferdinand Porsche stole his best ideas from Hans Ledwinka) and one that can earn you a severe caning at a PCA chapter meeting, needless to say.

Tatra did take legal action for patent infringement, at about which point Germany invaded Czecholslavakia. After the war the case was pursued again and VW was eventually compelled to pay Tatra something like 3 Million DM in compensation.

[McGuire]

Originally posted by desmo
Old school karters will recognize Walbro as the maker of a nice crankcase vacuum powered fuel pump that doubled as a carburetor.

Quite right...and oddly enough, yet another battleground for a piefight over patent rights as Tillotson fiercely protected what it saw as its exclusive claim to the diaghram-type carburetor. Forgot how that one came out though...and everyone else is probably wondering why anyone would know it in the first place. That's me -- fountain of useless automotive information.

[soubriquet]

All my Minis (13!) had electric fuel pumps tucked up inside the rear subframes. They were, I think, by SU, but may have been Lucas. My guess is that the Walbro was a convenient replacement for the original.

Mine were all totally reliable.

Brian: I share your opinion. The Tatra was an air cooled V8.
McGuire: thanks for the information. Fairly telling.

My first car was a 59 Beetle. It was evil. I have a real problem with FP's deification when he persisted with trailing arms and swing axles from when (late 20s?) till when (mid 50s?). That is over 20 years without consideration of suspension geometry or then-current developments. Or am I wrong on this?

Cheers
S

[275 GTB-4]

Wow....talk about setting rabbits running...this thread has everything!!! Cheers Guys

McGuire
Ah yes, the Autopulse fuel pump...those things have been around since the 30s or 40s. (They were used on big trucks and a few cars, Cord I think.) Walbro bought out Autopulse in the 1950's so you have a newer one. Walbro is still in business so you might try contacting them directly, or try a marine supply house since this pump was very common in pleasure boats. Electric fuel pumps like to be close to the fuel tank so they can push rather than pull. Where the pump is pulling the fuel is more prone to turn into vapor. The ideal setup is next to the tank and below it.

Great, the pump is ideally situated on the rear subframe, below and in front of the tank, about a short foot of braided hose away. I have a buddy in the 'states so I might get him to do some shopping. I was a little concerned about haviing an "orphan" but I imagine that the bellows type of pump are highly reliable - would not get used in boats etc.....

CFD Dude

Is this an electric pump? If it is I'd suggest going to the BMC mechanical one for your 850 unless you're switching to fuel injection. It runs off the cam and they tend to work quite well. We did that with my brother's Mini (1980 Mini Layland 1000, but we switched it to a 1275 Metro Engine) just for convience and it seems to work just fine. Any mini dealer should have lots of the mechanical pumps around.

Yes it is a 12V pump, and no way dude, it might be a 40 year old 850 rolling shell but I do intend to put an engine in with a little more grunt than that required by the District Nurse ( ). Therefore the puny machanical device will not get a look in. Similarly the small, unprotected fuel lines!!

Rosemayer - thanks for the link.....it looks like a bellows type

McGuire - Thats it! (well similar anyway)
This is the classic Autopulse/Welbro/Dupree fuel pump of myth and legend. The website says they carry repair kits and everything, or you can get a complete new pump for $80 - $100.

I would assume the electric pump was installed because the owner was feeling racy, or was suffering vapor lock problems, or the original mechanical pump failed, or this car once had a larger engine and/or multiple carbs, as the OE pump on BMC cars sometimes had trouble keeping all the chamber pots filled, especially under accel & cornering etc.

Ya got that right McGuire!! But for the time it was all bleedin' edge stuff!!

DESMO
Old school karters will recognize Walbro as the maker of a nice crankcase vacuum powered fuel pump that doubled as a carburetor.

Like I said, dis thread has got the lot!!


soubriquet
All my Minis (13!) had electric fuel pumps tucked up inside the rear subframes. They were, I think, by SU, but may have been Lucas. My guess is that the Walbro was a convenient replacement for the original.

I bow in your presence soubriquet, you must have no skin left on your knuckles at all!!!
I am in the local Mini CC and we are still having fun. Te SU/Facet pumps seem reliable but some do have "points" in that need maintence. All your Minis totally reliable??? Unbelievable!!! (only joking)

Mini has probably one of the largest smile factors around ;)

[Greg Locock]

Yeah I could post an uglygram of my knuckles. But as you say, grin quotient.

[McGuire]

Originally posted by soubriquet
All my Minis (13!) had electric fuel pumps tucked up inside the rear subframes. They were, I think, by SU, but may have been Lucas.

Hunh. You don't say. For your information, I have in my possession a number of rather distinct mental pictures of the Mini engine compartment which PROVE it had a mechanical fuel pump.

Apparently my memory is having me on once again. Oh well, not surprising. Sometimes it takes me a half hour to find my eyeglasses.

[BRIAN GLOVER]

Story of the Mini n Speed starting now. 10am

Originally posted by McGuire


Hunh. You don't say. For your information, I have in my possession a number of rather distinct mental pictures of the Mini engine compartment which PROVE it had a mechanical fuel pump.

Apparently my memory is having me on once again. Oh well, not surprising. Sometimes it takes me a half hour to find my eyeglasses.

[McGuire]

Back in the day, The Done Thing with these pumps for drag racing etc. use was to mount two, three, or even four ( ! ) of them back at the tank, then plumb them through one 1/2" or 3/4" ID line up to the front of the chassis, thence through an adjustable pressure regulator (cribbed from an IH truck) to your two great hulking Holley carburetors.

Seems like ridiculous overkill but actually it was necessary to overcome fuel inertia in forward (and upward!) acceleration. Though it took them forever to get around to it, eventually Holley introduced a proper pump for this usage -- big fat electric motor with a rotary impeller.

[275 GTB-4]

Originally posted by McGuire
Hunh. You don't say. For your information, I have in my possession a number of rather distinct mental pictures of the Mini engine compartment which PROVE it had a mechanical fuel pump.

Apparently my memory is having me on once again. Oh well, not surprising. Sometimes it takes me a half hour to find my eyeglasses.

Hey McGuire, you are looking over the top of the engine, between the firewall, exhaust manifold and the radiator.....bolted to the side of the block....thats where all the mechanical pumps are fitted.....on the single carb Minis.

Now....

carefully get your head out from under the "hood", walk around to the trunk of the Mini, get down under and look at the kerb-side side of the subframe (under the fuel tank in the trunk)....thats where they mounted the SU pumps for the sporty twin carb Coopers etc!!

The fact that BMC sometimes did unbelievable things like putting the earth for the pump in the roof lining on the passengers side is whole nuther story....Lucas electrics!!!!

[McGuire]

Originally posted by 275 GTB-4


Hey McGuire, you are looking over the top of the engine, between the firewall, exhaust manifold and the radiator.....bolted to the side of the block....thats where all the mechanical pumps are fitted.....on the single carb Minis.

Thanks, it's good to know I haven't gone totally senile. I can picture a mechanical fuel pump on these cars plain as day, and was starting to wonder if I had just made it up or something.

[soubriquet]

I'm going to have to confess this one. All the Minis I remember had electric fuel pumps, but like McGuire, my thumbs are twitching. I was bottom feeding on early cars and vans, but my mother had a new one, and that may have been mechanical.

The OE pumps were SU, and could run without attention until the car died. Mine never gave trouble. I knew people who fixed theirs with new points.

275 GTB-4: shouldn't blame Lucas for BMC's wiring of an SU pump.

Yes, I know all about skinned knuckles. It was good training for the epiphany: real carburettors came attached to Lancia and Alfa Romeo.

Cheers
S

[McGuire]

Originally posted by soubriquet
275 GTB-4: shouldn't blame Lucas for BMC's wiring of an SU pump.

On any production car, where they run the grounds may make no sense from a service perspective, but makes perfect sense from a design or production engineering POV. The wiring harness is one big assembly, installed and secured all at once as much as possible -- and of course it goes in early, before all the finish and closing trim. So it is very common to have say, the ground for the front parking lamp harness located somewhere in the front kick panel area, buried under the trim of course. Seems stupid, but it's all very logical if you understand what they were doing. Also, it is always preferable to have the grounds out of the weather. And of course it also helps on the service end if the wiring diagrams and manuals are clear and accurate.

To me bad grounds are fun and intriguing to track down. My favorite is the "backfeed" fault. For whatever reason (loose screw etc) a circuit cannot ground through its normal path, so its current backtracks up a shared ground wire through another load that is shut off, thus turning on both loads but with high resistance. If you ever saw an odd lamp on your dash or one marker lamp bulb just barely glowing all the time for no apparent reason, that's probably what's happening.

[275 GTB-4]

Originally posted by McGuire


On any production car, where they run the grounds may make no sense from a service perspective, but makes perfect sense from a design or production engineering POV. The wiring harness is one big assembly, installed and secured all at once as much as possible -- and of course it goes in early, before all the finish and closing trim. So it is very common to have say, the ground for the front parking lamp harness located somewhere in the front kick panel area, buried under the trim of course. Seems stupid, but it's all very logical if you understand what they were doing. Also, it is always preferable to have the grounds out of the weather. And of course it also helps on the service end if the wiring diagrams and manuals are clear and accurate.

To me bad grounds are fun and intriguing to track down. My favorite is the "backfeed" fault. For whatever reason (loose screw etc) a circuit cannot ground through its normal path, so its current backtracks up a shared ground wire through another load that is shut off, thus turning on both loads but with high resistance. If you ever saw an odd lamp on your dash or one marker lamp bulb just barely glowing all the time for no apparent reason, that's probably what's happening.

Yes.....you are correct in that production lines spawn crazy complications for car owners....just look at the way some air con/heater cores have the car "built around them".

Sorry McGuire, but I cannot forgive the SOB who decided to put the ground for a rear sub-frame mounted fuel pump in an interior roof gutter!! A common Mini modification is to provide a decent ground ON the sub-frame!

I have a car with the dreaded half glowing warning light and it is frustrating in ther extreme....is there a fault?? or is just a bad ground??? Doooohhhh!!

[McGuire]

Originally posted by 275 GTB-4


Yes.....you are correct in that production lines spawn crazy complications for car owners....just look at the way some air con/heater cores have the car "built around them".

Sorry McGuire, but I cannot forgive the SOB who decided to put the ground for a rear sub-frame mounted fuel pump in an interior roof gutter!! A common Mini modification is to provide a decent ground ON the sub-frame!

I have a car with the dreaded half glowing warning light and it is frustrating in ther extreme....is there a fault?? or is just a bad ground??? Doooohhhh!!

If I am purchasing a production car to be used on a miserable little island in the Atlantic racked with wet, salty winds, or in the snow belt of the USA for that matter, I wish to have the grounds located inside the car out of the weather.

For the same reason, if on my own equipment I locate a ground on the underside of the chassis exposed to the elements I am asking for trouble. It's also considered bad practice: if a knowledgeable person spots it he will brand me as a wanker. In a sanitary wiring job grounds should not be visible anywhere, except neatly under the dash or in the engine compartment. This is a point of shame for the quality mechanic-fabricator, like being caught using Scotch-loks instead of making proper solder joints. On the other hand, when the ground attached to the underbody metal with a sheetmetal screw fails, as it eventually must, I suppose it will be easily accessible.

On the glowing lamp problem, I would whip out the wiring manual, turn to the page with the ground callouts, identify the ground location for that circuit and test it. (No more than one-half volt drop to the negative post of the battery with a low-impedence VOM.) I would also note from the schematic which other circuits share that specific ground lug and see if they are working properly.
The interesting thing about electrical wiring problems: there is usually more than one symptom, allowing you to triangulate and zero right in on the trouble.

[275 GTB-4]

Hmmmm I can see where you are coming from.........we are lucky here in that we live in a largely salt free and benign environment....but on snow and salt laden roads the story would be different....anyways.....that SOB could still have found a more convenient ground in say the trunk!!

Good to see a different perspective for a change......thanks for the electrical tips....I'm on it!!

[McGuire]

Originally posted by 275 GTB-4
Hmmmm I can se where you are coming from.........we are lucky here in that we live in a largely salt free and benign environment....but on snow and salt laden roads the story would be different....anyways.....that SOB could still have found a more convenient ground in the say the trunk!!

Goo dto see a diferent perspective for a change......thanks for the electrical tips....I'm on it!!

All apologies, I'm sure my sermonizing was overly umm, overbearing. I am the original anal retentive mechanic. However, it is not for me to tell other folks how to service their cars.