I'm offering a kit which includes a diaphragm, o-rings and paper gasket, to rebuild D-Jet MPS units.
I already obtained an acceptable quotation on the most challenging component - new stamped beryllium copper diaphragm pieces.
The sample I used for CAD was the "triple ripple" shape which I think is the most recent design from Bosch.

The mild steel hub pieces will be zinc plated just like oem. We will swage the hubs onto the diaphragms in-house.
Your adjusting screws which thread into the diaphragms will be re-used with new o-ring provided in the kit. A new o-ring to seal the housing is also in the kit.

A new full load stop screw is the centerpiece of a tuning kit which also includes a special 7mm hollow hex driver and correctly sized flat blade screwdriver.
The stop screw has an 8mm hex thru hole instead of the large slot in the originals.
Adjustments will be made without removing the stop screw.

Someone else might be interested in providing assembly/adjustment services. I could do that too, but we aren't set up for it right now.

CAD:
Click to view attachment

Production pieces:
Click to view attachment

Edit 12/08/12: Final Production begins soon.
Current prices: Diaphragm Kits-$127.95; Tuning Kits-$46.95; Both Kits Together-$166.95. Shipping Included
Order from our Whats New Page.

Count me in for at least one kit.

Thanks for setting this up - there is definitely a need...good used ones are getting hard to find and cost a lot of ca$h. I hope we get enough interest.

Great idea. Hard to be patient for 4 to 5 months. I'd be game.

would these be for any mps, or particular ones? I'm in for more than one regardless.

Would have been in on this if it were not for MegaSquirt.

chris, this is great! not having this piece is the main reason we have not been able to rebuild these ourselves without scavanging from others-- and the last one i got from automotion/eckler's was crap!!! and got returned. I have a box of 5 or 6 that either need new diaphragm, o-rings or both... so i will be in for a couple at least.

p.j.w.

In fact, the MPS and its status as an unobtainium unicorn is probably the #1 reason I went the MS route.

Plus the trigger points are NLA also. Being able to service the MPS is OK but if there is still no complete stock of replaceable parts for the D-Jet system then new systems are the way people will keep 914s on the road.

Looks promising! Please keep us posted on the progress and let us know the final amount and where to send money.

AFAIK the same diaphragm is used in all MPS models. Different ones I've seen are the result of revisions to improve performance.

I think the difference in 1.7s/2.0s are due to tuning more than diaphram.
Th MPS should need to be recalibrated, just as it would if you changed out for a workable "used" diaphram.

I would be interested in one

i would take at least 1.

k

Absolutely. Number one part that is killing our F.I. You can purchase a used one and it could be fatigued and fail in a day. If it helps I would commit to purchasing two. Send an pm when you make it. Storms hit here so I may miss the notice.

I'm in

I have about twenty sets of trigger points if anyone needs them.
$25 a set shipped. I did find new sets still available for about $135
Bruce

Chris,

I know a board member here (MDShantz) that does recalibration of them. He may be willing to do that so members could get a finished unit. Question is what price will the market bear?

I have about 20 mps units most of which are leakers.

Bruce

Chris, I am not as technical as you guys so I am not sure what this does or where it fits. I have a 73 2.0, stock except for points replaced with the Pertronix module. I want to stay stock and this sounds like something I will need in the future and may even need now but don't know it! Could you explain in laymans terms what this means to us non technical people, if I need one I'm in!

Ian Stott
Moncton
Canada

It's a rebuild kit for your MPS. Get one. If you don't need it now, you will later. The people how can rebuild/calibrate the MPS units are many. The berylium diaphram is unobtanium. I'm in for 1 or 2. And a million thank you's, Chris.

IN

I'd be in for one at first to see how it all works. Then I could potentially need 20-30 more for the box O cores in my stash. I can also assemble/calibrate for others.

Put me on the list.

I haven't seen Scott post in awhile but he was calibrating MPS's for a few members, he might be interested in doing it as a service.

I am in for one at least.

Folks may want to jump on this so you can have a spare for the coming years.

No one has ever made these before aftermarket afaik.

John

Nice addition for D Jet owners, way to go Chris !

This sure hurts the value of the NOS MPS that the PO supplied with my car.

I'm glad a solution to to the MPS problem is at hand. Stock FI is a joy when it's right and many 914s will be able to stay stock with this advancement. Good work Chris.

Count me in for one set.

--- Rob

I will be in for two! Please advise how and when to pay.

I'm in for 1.

I'm in for 2.
Keep us posted when you need the $$$ to get it started.

Yep, I am interested.

YES! im in

My MPS hasn't been exercised in well over 20 years - no idea what shape it's in. While MS or some other standalone is probably in my future eventually, I think I'd best get one of these.

Hello there,

ther is also the possibility to get your MPS rebuild and calibrated by Bosch.

It is not cheap. The quote I got was 293 Euro plus shipping.
You send it to Bosch. They check it. If it's ok you get it back but with 19 Euro handling cost. If it is damaged beyond repair you get it back for free.

Its on

www.automotive-tradition.de

Peter

I'm for at least one. Perhaps two.

What equipment/tools would be required to assembly and calibrate the kit?

+1, thanks,

Assembly is easy. I used a propane torch to help with the epoxy on the screw. It is possible to damage teh screw and threads and took me an hour at least to remove it due to being careful.

calibration requires either a wavetek (sp?) meter or it can be calibrated with a wideband oxygen sensor on the road or dyno.

I will take two. One for the one in the car and one for the one on the shelf.

I think I'm going to offer the repair kit without the full load stop screw, and sell that separately with tools for adjusting the diaphragm screws.
I got some more parts quotes in this morning. I'm almost certain the kits will be priced below $100 (including shipping) for the group buy.

Help me here and no disrespect. what would be the advantage ( your quality would be better) to buy your kit when I could buy off the rack a MPS rebult from one of the main steam venders.
Wes

Chris.....Excellent idea...Count on me for 2 ............Jerry

I've never bought one of the rebuilt units available from PP etc. but others have commented on poor quality/performance. For one thing, I don't think the re-manufacturer is using a beryllium copper diaphragm.
There are lots of broken units out there being stored for the day when new diaphragms become available.
They are a potential DIY repair component for the more adventurous 914 owner.
Anyone who wants to tune their own D-Jet FI with a wideband AFM installed needs the assembly to be adjustable. The remanufactured units are most likely epoxied shut again, making them non-adjustable.

I believe that PP would get their units from Fuel Injection Corp (Old Brett Instruments). They used a stamped steel diaphragm which didn't have the same flex characteristics. Whether they actually calibrate them is a question.

The ones I had rebuilt by Python were not calibrated and they didn't disturb the expoy. They used used diaphragms from other units.

The only one I knew that would calibrate them with a Wavetec was Blyseng.

I don't know what George does.

You could offer the kits to the rebuilders too! There a hundreds clamoring for MB, Volvo, VW, BMW, etc units.

Sorry for the lack of posts lately, The car is running great so I've been indulging myself in RC Helicopters....

I have access to the proper meter at work, but would consider purchasing one if I could break even doing some calibrations.

My experience indicates that at a minimum the factory calibration is way to lean if you have an aftermarket exhaust.

It also indicates that another couple of turns out gets you a good running car, but I think the right way to tune these is on the car with an oxygen sensor.

My theory is that with tightening emission standards they set cars to lean kill in the seventies, add 10% ethanol and you are leaner, popular mods and you are leaner still....

So be careful in what settings you ask for or be prepared to be dissapointed!
Chris I don't need one right now (I have a good copper one for now), but would be interested down the road.
If I "had" to buy one now to make it worth it to you I would.

I agree from experience.

Recieved a rebuilt unit from FI Corp. They sealed the end so I would assume initially it was set. The car ran "ok" but I have found that it IS running lean...especially under full load.

I think they are also running a steel diaphragm as Ron says, so I am not sure if that is the problem or not. I know this....when I ran the original....it ran better through mid-range and top end for sure.

I am committed to FI but am yet to be convinced that the MS is better although the conversions done by a few look interesting.

I will be installing an AFR meter in the car and then reset the load settings if I can on the rebuilt unit.

I have digressed from the original post..... I am interested Chris.

I'll just sell stuff till I hit $130.

Put me down for "1"

I have a box of used-less ones as well

I have a couple used ones as well... No need to rebuild though... I am running SDS

I admire your willingness to take this on. I actually looked into this as the procedure for duplicating the part is not too dificult, not inexpensive, but the material but parts can be made. The main issue I ran into with these is how do you callibrate it correctly?

There is a thread I may be able to find that detailed the measurements for the outputs. This will be helpfull. The main issue is the reassembly, not just putting it together, but at what presure. The base line reading will vary with the pressure altitude at which it's assembled.

The "standard" I would assume would be standard day at sea leavel 101.3kPa. The other part of the equasion is the temperature, it should be 15C at this pressure.

I'm not too sure how close is close enough, but calibration will more than likely require some equipment, unless you are at standard pressure and temperature. Then you could just close it up and check the output.

And yes, if this can be worked out put me down for 1 as I have a dead one also.

I agree with the lean issue.

Put me down for (1) rebuild kit.

Tom

I'm envious of you guys who have the ability to make this stuff! Well done!

I'm in for 1.

Yeah, they used the steel diaphragm that gave a less than smooth transition compared to the OEM MPS units. I have a box of 50 dead MPS units and could make a run of em if I had the diaphragms. Using a Wavetek its easy to calibrate em just like in the Factory as Bosch used something similar to make batchs of them.
For a 2056 I use my car as the baseline with a LM Meter as MPSs have to adjusted in a car for the correct mix vs a Wavetek to get "right". I just didn't have any luck using the Wavetek to make a batch of MPSs for a 2056.

The other variable is the ECU's as for a 2.0l there is the 73 one, the 74 one and the 75/76 one. They got leaner each year from what I have tested. But if you have a stock cam you can use a stock calibrated MPS set up witha Wavetek.

IMHO the PP ones were set up too lean at WOT maybe setup for a 1.7L so a 2.0l will run lean using them.