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Discussion Starter #1 (Edited)
Forgive any dumb questions here, but I've got a lot to learn and am not sure where to start, so let me begin rambling.

What does anybody know about the early Hartig ignition systems? I'm going to attempt to get mine reinstalled and running. Previous owners removed it due to undiagnosed intermittent problems. I suspect the problems were all wiring or sensor related.

The system has a sensor mounted in the bellhousing to read the flywheel ring gear. It looks kind of like early Motronic stuff, except that on the motronic car there are two sensors, one reading on the teeth and one reading back further on the flywheel (the first is getting rotation speed and the second is getting a reference position).

The ring gear and sensor (see press photo) appear to be specific Alpina parts. Any ideas on how the system works? Presumably counting teeth for rpm, but how's it getting a reference mark? Magnets imbedded in the ring to give it "missing teeth"? If not magnets, how else could it be getting a reference position? Or is it not reading teeth at all, and is strictly a "flying magnet" type setup?

If there are indeed magnets in this ring gear for it to read, do such magnets lose strength over time such that they would be the cause of erratic problems (as suggested by the mechanic that removed the system)?

What kind of sensors are these (pics below of the two I have with the car). Standard inductive rotation sensor or Hall effect? Think it would it be the same in function as a bosch/motronic or other readily available toothed wheel sensor? Some mounting work work would be required, but would they likely function the same? Or would it work, but I'd have issues with wrong output signal voltage or something like that? Could I adjust that by adjusting the air gap?

What should the air gap be on something like this? I believe my Alpina manual says 0.5mm. That's pretty tight, but maybe necessary if it's trying to read magnets deeper in that ring gear.

Pic of the two sensors I have is below. One is a later replacement offered by Alpina (I believe, still waiting for a reply from them). Note that both appear to have come in contact with gear teeth at some point, hence my question about air gap. And would you suppose these might still be functional? Can they be tested and how?

Looking forward to learning something about a new field for me here.

Thanks,
Mike
 

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My system just crapped out too on my E21. Ive determined there is no signal going to two of the coils coming from the control unit (silver box). That is most likely your problem too. The sensors are probably still in tact. Im puzzled as to how that sensor reads the rotations too. Only thing I can guess is there is a groove or something on the inside of the flywheel where you cant see, that gives the magnet the signal.
Im glad to know other cars besides the B6 used this unit because maybe they still have them in stock. As far as I know Hartig is out of business. Im sure Alpina will ask for your first born for one with their crazy prices.
I sent my unit out today to an electrical specialist, so maybe its something simple that can be repaired, although I doubt it. My fingers are crossed. Any info you gathered would be great. :thumbsup:
 

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Discussion Starter #3
I don’t know if Alpina is still repairing/replacing the Hartig boxes.
I know they no longer have the crank triggers or any of that.
The original coils are NLA, too, although I hear they do at least have something (non-original) to replace them.

The basic system looks the same for B6 and B7, just presumably different programming in the box. That doesn't really help much though, although I suppose it slightly increases the pool of cars on which you could theoretically test parts to determine if they're still working.
 

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How did you repair yours? I just sent my box out today, so Ill see if they are able to fix it. I think the coils are not too important, as they looked like batteries wrapped in electrical tape. Simple BMW motorcycle coils should work, and that is what Im planning on using. The price through Alpina was 300+ per coil when I checked a year ago. They originally told me they had them and then told me also they were NLA. I never inquired about the control unit because it was operating at the time, but now I will need one if they cant fix it.
 

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Discussion Starter #5
Have never tried repairing mine. Previous owners tried unsucessfully to do so through local/private electronics shops here. They eventually sent back to Alpina for new units.

So, some background from when I came into the picture and took ownership:

I have two boxes and two pickups for this car. Not positive which pieces were on the car last, but when they were taken off it was working, albeit with intermittent problems (also described by p.o. as being high rpm and heat related). Without another working car or known good parts to swap out, previous mechanics felt unable to diagnose the system and so yanked and replaced it completely (they did so fairly delicately, so it can all be plugged back in). I suspect, given that the issues were intermittent, etc, that one problem was various wiring/ground faults around the system. My hope was that if I refreshed the wiring harness and plugged everything back in, it just might work.

Both of my crank triggers/senders look physically damaged, though. I never did get any good advice here, from Alpina, or elsewhere about how to determine if either of them are still functioning properly, or if a replacement could be sourced. Bear that in mind as you troubleshoot yours - crank triggers are NLA from Alpina. And let me know if you have a good electronics guy that can figure out how to source a replacement.

The mechanic that had previously worked on the car decided that the magnets in the flywheel were likely the problem and, as replacement flywheels were also NLA, ditched the whole system.

I tend to disagree with his analysis, although I suspect he may have been on the right track. The damage to the sensors suggests to me that the gap was incorrect. Could you pop the front cover and see on your car what the air gap between the sensor and the flywheel teeth is? Also, a picture of the mounting bracket for the sender would be extremely helpful. That’s the one part from the system that is missing. Perhaps it’s been missing for a long time, hence the mismounted sensor, intermittent hot/high rpm issues from the wrong air gap, and resulting damage from hitting the flywheel teeth.

The more I research, the more I think I’m just going to put on an aftermarket modern crank-fired ignition system (the car’s running on an MSD and 635 dizzy right now). I’ve got a couple of TecII units that, particularly if I can use them with the original coils, would provide an almost invisible upgrade. The hartig system, while very simple, is starting to look unmaintainable. There’s current stuff out that does the exact same thing, just in a different box.
 

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I think so too. I will try and take some photos next time Im at the shop. I was told by the mechanic that changing the ignition system on the car would not effect its performance, but wouldnt Alpina have wanted to be very specific with the timing installing this custom unit? Even the later cars were run through a brain and a specifically timed distributor.
 

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Discussion Starter #7
Thanks, that would be greatly appreciated. Might have to pull a few little bolts on the front trans cover to pop it off to get a good view of the gap and all.

As for timing, ehhh, there's really no rocket science going on there. Physics is physics and ideal timing/max advance is what it is. It would be nice to know what their original advance curve was (as well as what manifold pressure/temp adjustments were) but in the end, a few degrees of timing here or there is not exactly a propietary mystery. Start with a stock euro 528 advance curve and crank in a little more for a beginning. I'm sure that's all they did. If you can get it on a dyno for a little tinkering you can certainly match or better the original, or hell, just keep bumping advance til you get a little pinging and back off, throw a few degrees retard in for higher intake temps, and you won't be far off from what any other tuner (Alpina included) would come up with.
 

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Hello my name is Krister Hallin and I am the owner of B7s turbo No 49/60 I' also got a problen with that, I was out driving and suddenly went car out? and I've tried everything I know! I could not get spark from the ignition coil? so I was told that I should change so this Rafi sensor, but where can i buy such an sensor, now I read that it may be the silver box that is perhaps the problem, can anyone tell my wher the
box is sitting in the car ????????????

Thanks
Krister
 

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Ignition Problem

Hi Krister,

I have a B7S #17 here in New Zealand and I had similar issues. The crankshaft sensor had stopped working and also damaged the control box by shorting it out. The control box is repairable but the "Rafi" sensor can not be found anywhere worldwide. My solution is in another thread on this forum "E12 B7S" Have a look and if you have any questions send me a message.

Kind Regards,
Mark.
 

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oh my god it does not sound good, I have checked the box ignition but it looks fine there is nothing that is burned, it's really really that there is no sensor that can estate that rafi sensor, it sounds like it must have a brand new ignition system?
but thanks for your help,
I know some people in munich at BMW mayby that they have a good idea

thanks
Krister
 

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Discussion Starter #11
Please try other avenues to find a replacement sensor. As you might have noticed in my original post, my car came with a second non-rafi sensor, so it does appear that someone at some time had figured out another replacement.

The idea that the cars become static display pieces because Alpina won't support us finding something as fundamental as a replacement crank sensor is an appalling notion.
 

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Ok thanks for your help, yes I will see if I can find an alternative way to the make it run again, and yes I called alpina and I must say without being harsh in my language, they were not very helpful, you would think that they would be interested to see the old cars running!.
However, ther most be some sensor that can replace the old rafi sensor ! :confused::confused:, I spoke to the people who made the management of supercar Zenvo and they want to Helping me if I do not find anything else .
 

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hello
Lately I've been lucky and have got hold of Alpina employee Sir Alex Rimpler, and he has been very helpful. since my alpina is a B7S Turbo I have an AFT ignition box instead of Harteg (do not know if there is any difference) but it was mentioned that there are 3 things that can be broken matal plates on the flywheel sensor or AFT box ,

Then I was offered to send the Box and sensor to
REZ
Reparaturservice Electr. Zündanlagen
Mr. Andreas Nithammer
58840 Plettenberg
D

So now I am waiting for a reply from them if it is box , sensor or flyweel
:crying2::crying2::crying2::crying2:
 

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Crank Sensor

Hi Krister. I hope it is the AFT Box. Yes these can be repaired as I repaired mine easily here in New Zealand. I hope it is not the flywheel sensor because then you will be back to square one! Any auto electrician should be able to test the sensor and tell you if it is working or not. In my case the sensor became faulty and then shorted out the AFT Box, I fixed the Box but then could not find the sensor. Did you ask your Alpina contact if he can suggest a flywheeel sensor that will work? I would like to return my system to original instead of the alternative hybrid system I have now. Please keep us all informed. I am sure there are many who would like to know the answer. I think these sensors are the same for B7 and B7S, only the ignition box (Hartig for B7 and AFT for B7S) is different.
 

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Hi there people,
I myself am being confronted with ignition problems with my 1979 BMW 630 which was converted (by Oldenhof, the Netherlands) in 1980 to Alpina B7 Turbo specifications. I've got the oldest engine configuration: 3.0 liter M30, Pierburg mechanical injection, originally supported by Dr Hartig ignition with the 3 coil setup, but unfortunately the ignition box has been missing since I bought the car back in 2003 in a rather sorry state. Some 10 years later, the car is been brought back to life hopefully, the body has been restored to a rather good peace of work but I'm still struggling with the ignition issue. Since I would like to leave the car as original as possible (even if the car is not a proper Alpina on paper), there are to my knowledge only 9 3 coil-equipped Alpina's that I know of. To encounter the ignition problem, I thought to be wise to purchase a original B7S ignition (Atf) some years ago for quite a lot of money, which now proves to be useless since I discovered that my car, other than a B7S from '81 onwards, has a different application on my fusebox and coils. It hjust doen't seem to fit. It appears that my car does neither has the flywheel sensor which is subject to this topic.

Maybe someone knows a solution to my problem without having to switch to the logical Motronic conversion? I consider to sell my Atf-ignition box since I appear to have no use for it (unless someone knows a solution which includes the use of this system combined with apllying a flywheel sensor). I is a original B7S peace which I bought for a lot of money from a German Ebay-connaisseur. Furthermore, I bought a full new stainless steel Alpina B7 Turbo exhaust system from the turbo onwards, with catalyst and lambdasond which belongs for later (Motronic) B7/1 use.

Thanks in advance for you're advise or ideas!

Kind regards
 

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Did you use that exhaust setup on your car or are you looking to sell it?:dunno:

Mine has been mismatched over years and is in need of replacement

Of Course NLA from Alpina:(

Paul
84 B7/1 coupe #012
 
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