Some comments... based mainly from what I've learned reading about and working on a Spitfire with SU's...

An electric fuel pump is an option, but be warned SU carbs can be picky about fuel pressure... too high will make them leak... so you will probably need a regulator in the engine bay to keep the fuel pressure under check. This may or may not require a return line back to the tank... (I don't think so, for such low pressure). Just about every aftermarket pump is designed to flow a lot more fuel than a Mini engine needs.

Electric pumps are better at pushing fuel than pulling it... so the best location for the pump is as close to the tank as possible and below the tank if possible so it is always primed by gravity.

IMHO, unless you're looking to do more upgrades, I'd stay with the mechanical (engine driven) pump.

 

the older mechanical SU pump is the 700 and it has a rebuilt kit but be aware there's more than just the main diaphragm in the kit. "SU Carburetters Tuning Tips & Techniques (also covers SU fuel pumps)" has the full rebuild procedure.

As best as I can tell the 800 series pump is a direct replacement. It has the same mounting specifications and was the standard on later cars...it's what I have on my 1275 A+. It is built as a sealed unit, according to the reference I note b4, to withstand higher underhood temps on newer cars.

Going price around $130 ....

 

Grrrrr.... tried getting the old pump off this afternoon... Can't get my ^%$#@! wrench on the inboard bolt. It's so bloody simple! I see what needs to be done! As is always the case, the real puzzle is trying to figure out how to get my hand AND the tool in there at the same time. ARRRRGH!!

 

It is hard to believe they put anything needing a wrench on the backside of the motor.. This challenge might give you cause to opt for the electric pump

 

The engine was designed to be used in a North / South orientation. When they dropped that lump in the Mini it became East / West. Lots of things were compromised by that placement. Yep it can be quite maddening.

Matt you just have to have the right selection of spanners & cuss words. Eric had a whole drawer dedicated to special home made & modified spanners in his tool box. Plus an encyclopedic knowledge of all the right cuss words to get the job done. Don't give up, keep on cussing & you'll get it.

 

LOL... Well I'm working on the cuss words... Thanks, Chuck!

 

You just need little hands like me....you know what they say small hands,small....uh...small...hmmm,eh.....well small hands help.I can even get the speedo cable out with no problem.

Crashton....Eric had special words for ALL situations. God bless Rex Karrs

 

I don't know if you got it out already but what sometimes works is one of those universal joint socket extensions. I sometimes even use two of them inline because they don't quite work perfectly at a 90 degree turn. Also when you use these it sometimes helps to put a little of something gooey in the socket which helps keep the socket on the bolt when you let off the tension. I have an old dried out tub of wheel bearing grease that does the trick.


http://www.northerntool.com/webapp/w...2999_200312999

 

Not out yet... I just made a deal with another NAM-mer (thank you!) for a replacement pump. As soon as it arrives, I will try again. I'll try that "wobbly" adapter - thanks. Someone also recommended a ratcheting box-end wrench (11mm) with a 6-degree throw - apparently, the space is so tight that an 11-degree wrench won't ratchet. I'll need to verify the nut size - I THOUGHT I was using a standard socket on the outboard nut (the only one I could reach), but I might be wrong.

QUESTION: When replacing the pump, how do I assure myself that the tongue (which rests on the cam) is in the right location? I can't see it, naturally, since the lever protrudes through a narrow hole the thermal spacer. Will I feel a positive "click" or some other type of feedback to assure myself that the lever is in place? I'd imagine if it's not right, the lever could be insta-shredded? Or am I worrying too much (which wouldn't be out of the question for me...)

 

The size may have changed over the years but a 1/2" or a 13mm both fit well on my 1275.

 

I'm running a $40 Facet Posi-Flo electric fuel pump on my Innocenti. Works fine. I also carry a spare with me, since I'm paranoid!

One thing to keep in mind if you go electric: Get the low pressure pump models, about 2-4 psi. The high pressure models (5-8 psi) are designed for fuel injection cars and if they are used in one of our carburated Minis, there is a chance that it will overpressure the float shut off needle and you will get fuel coming out of a vent. Use a pressure regulator if you have the high pressure model pump.

 

You mean like THIS ONE?

Going that way IS appealing... however I'd still need to pull off the mechanical pump and block the cam access hole with a blanking plate. And re-run fuel lines (which I fear may be beyond me). Anyone out there who builds race cars wanna help me?

 

It's ALIVE!!!!



The new pump wasn't that bad to get on. Hal (Classic Blimey) came by to share fuel line advice and provide me with moral support. He managed to get the bolts started on the replacement phase, as well - thanks SO much man!!!

Yaay!! I've missed my lil' car!!

 

Sure was nice of Hal to help you out.

Attaboy Hal!!!

 

Did you fix it?

 

Matt,No problem man aways glad to help.Just glad I found the bolt I dropped Told ya small hands help Nice day to play mini mechanic. Gave me an excuse to get the Cooper S out too! You gotta bring it here next time so we can have some tunes and get outta the wind

Running when I left so I guess all was well!!! Yaaaaaaaa baby!

 

Chuck ,Always glad to help out another classic Mini owner. Hey ya gotta get me into the old fart club!

 

Yeah - I drove her downtown and then out for a night on the town - she's running like a top (for now).

 

What did you end up doing? Just replacing the old with a new?

 

teamwork ....

 

Yep - yanked out the old pump and put in a new one. I'll probably take the old one apart and see if it can be refurbished, just so I have a spare, but the new one is crimped shut and has no bolts or screws to loosen, so hopefully this won't happen again.