1969 2.0 911 freshen

[NickSi]

Hello this is my first post here at pelican parts. My father has a 1969 911E which i will inherit when he feels like giving it up. He rebuilt the engine when i was 3-4. ~15 yrs ago. he has replaced a few components that went bad. one was (well im not really sure what it is. it is the part that is the "heart of the MFI system. My father reffered to it as the fuel pump but i don't think that is what it is called) the fuel system. he replaced the leaky unit with a weak unit that he found in Panorama for ~$400 a few years ago. ever since then it has not been as powerful. i know the Es were never really very powerful but its a little embarassing when you can't keep up with some yahoo in a family sedan. we still have the old unit. how much do they cost to rebuild? could i do it myself? how much are new pieces? should i just screw the MFI and Webber it? any advice from people who have done this would be greatly appreciated!!

[tadd]

Several folks do service and rebuilds on the MFI (mechanical fuel injection) pumps. Pacifica Fuel Injection and Supertec come to mind. PFI has been doing them for a long, long time and are considered 'the source'. They are not cheap. Figure 1.2k for a service w/o parts. I have never seen Supertecs prices. There are others, but you get what you pay for.

It is MHO the MFI pumps are not rocket science (someone had to build them in the 60s no less, right?). Check out this thread.

http://www.pelicanbbs.com/showthread.php?s=&threadid=283059&highlight=gods+MFI

That said, I haven't put one back together, tuned it and see it work correctly yet. I'm getting ready to move for a new job, so it is on the back burner. You will need to machine out some special tools (since they are NLA) to get it appart so one should consider it a project for the brave/foolish. Check out the technial section of this site for a pdf of the factory MFI manual. All the instuctuons are there for disassembly. Read it several times. You may just need to adjust the linkages. THat makes a huge difference. Again, the pumps are rock solid.

The pumps keep their calibration for a long, long time (100+K miles) so take it off, pack it in a box, pay the fee and then reinstall for years of trouble free operation.

Oh yea, they run about $750 for an S spec pump in A+ condition so a few hundred less for an E I would guess. That would be an 002 or 006 pump depending (last part of the serial number).

tadd

[kenikh]

Don't toss the MFI. Don't add carbs unless as a last resort and then, keep the MFI in a box anyway. Where do you live? There are a number of places to send an MFI pump (that is the part you are talking about) to have it repaired or rebuilt. FWIW, you can't rebuild it yourself; the tools to do it are pretty much unobtainable today and you'd have to machine them yourself.

Places that do this work:

Pacific Fuel Injection
Supertec
Eurometrix
Otto's (I think)
Fairchild's

[NickSi]

So from what i am hearing i should just send the unit out. Or maybe the unit is just not calibrated correctly. is there a way to calibrate it easily. and how do i tell if it is lean rich or not correct?

[NickSi]

ok i just read that there is a goveneur on it would removing that make more power? that sounds like it probably wouldnt but i figured i'd ask.

[tadd]

There are seveal control circuits that all act on the 'main rack' that rotate the 'control sleeves' which inturn change the volume of fuel that is squirted. The 'Governer' is an RPM control and there is also a load contol (throttle position). In addition there are barometric and cold start circuits.

I would get the basic tune up pdf from the tech section and make sure the linkages are adjusted properly. They will have a profound effect. The pump/control units are very solid pieces and usually only need attention when left to set for a long time (like pulled from the car and not 'preped' correctly - ie use calibration oil for storage). Make sure everything else is tip top before messing with the linkages. You will need to purchase or borrow a set of protractors to set everything.

There is a small screw on the end opposite the belt drive that controls the main enrichment. A hand held O2 meter makes this easy. So does a dyno, but it can be done without.

tadd

[304065]

Start here:

http://www.pelicanbbs.com/showthread.php?threadid=270610&highlight=ultimate+mfi

Do not start adjusting the pump until you have read everything about the system. Do not attempt to disassemble it, there are only half a dozen people in the world qualified to reassemble and calibrate it correctly.

Search here for "MFI" and "Grady Clay" or "Early_S_man", you will discover a wealth of knowledge which can help you resolve any issues with your '69.

Good luck! How about a picture of the car?

[911pcars]

NickSi,
Before spending considerable sums rebuilding the MFI, I'd suggest an evaluation of the engine. If it has good compression, doesn't burn oil, no massive engine leaks, chassis is sound, etc., then go ahead and make the fuel system whole. If not, consider the costs involved before making the leap, or at least allocate the funds necessary to do this in logical steps. A pristine FI pump does no good in a weak engine.

Best wishes,
Sherwood