L-jet to Motronic Conversion

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Odometergears
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L-jet to Motronic Conversion

Post by Odometergears »

Here is one for all you conversion folks.

I am taking an M30 block and head, 2.8L with a 79 casting to be exact, and converting it to a motronic setup. I'm leaving out a lot of details on purpose.

Right now, I want to focus on the combination of the upper timing chain cover and the thermostat cover. The long block is back together. I went to put the thermostat cover on and it hits the upper cover where the cap will be going. I've looked at the part numbers on RealOEM.com and some years are the same part and then others are different. What year and make thermostat cover do I need? After I get one that fits, can I use the same hose or do I change the radiator to an E28 out of simplicity? I will go back and read up on the FAQ some more but if someone has the short answer, I am all ears.

Jeff
Jeff Caplan 1981 Euro E12 3.5 M106 Block w/T4
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wkohler
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Post by wkohler »

If you put the E28 radiator in, you would need the E28 thermostat cover to get the right angle on the lower hose, so given how the hose comes off of the E12 cover in relation (at an angle) to the E28 cover (straight down, away from the cap), I would think that would solve your issue. Plus, you could get the super-duper cooling capacity from the E28 radiator.

Of course, to use that cover, you'll have to use the E28 radiator, as I would think that would create an issue with the lower hose coming off the cover.

I hope that's clear enough. I can only hope the answer to your question is buried in there somewhere.
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Odometergears
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Post by Odometergears »

Here is the problem... I looked up the part numbers on www.realoem.com and came up with different part number for the thermostat cover. Which one is the correct part? I could use a year and model so I can get the correct other parts.


Jeff
Jeff Caplan 1981 Euro E12 3.5 M106 Block w/T4
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Mike W.
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Post by Mike W. »

I think they changed thermostats in around 86 or so, so it's possible the cover changed at the same time. I'm not even sure what the difference is, they are similar in appearance, but apparently not interchangable. I haven't looked at them side by side though.
Mike W.



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Odometergears
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Post by Odometergears »

Here are the part numbers to compare. I'm hoping the angle of the E28 will be aimed differently. It has to be. I'll post back after i get the new cover.

1986 535i
06 Cover 1 11531268650 $45.62
01 Hose 1 11531289859 $51.94


1980 528i
05 Cover 1 11531714861 $106.62
01 Hose 1 11531266462 $37.09

Jeff
Jeff Caplan 1981 Euro E12 3.5 M106 Block w/T4
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wkohler
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Post by wkohler »

Jeff, if you want, I think I've got a 535i cover and maybe an "A" housing for that cover in storage. I'd be happy to send it to you so you could confirm if it would work for you. Of course I'd need a day or two to find it.
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Post by Odometergears »

Christopher,

I'd love it if you can find it. Let me know about shipping and I can email you a fedex account number for Fedex Ground. You can email me at:

sales@odometergears.com or call 757-593-3478.

Text me if you can. I am forwarding all calls for the next week while I am at the beach. Leave me a time to call you back. I'm on the east coast so time should work out.

Many thanks

Jeff Caplan
Jeff Caplan 1981 Euro E12 3.5 M106 Block w/T4
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Post by Odometergears »

Thanks for the parts Christopher.

For the record, all you need is the cover. The difference between the housings are the number of holes you get for sensors. I have to plug a few. You will also need to get new bolts. Corrosion of course is the cause of this.

Engine is almost together. Will post photos soon

Jeff
Jeff Caplan 1981 Euro E12 3.5 M106 Block w/T4
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Post by Peter Florance »

Odometergears wrote:Thanks for the parts Christopher.

For the record, all you need is the cover. The difference between the housings are the number of holes you get for sensors. I have to plug a few. You will also need to get new bolts. Corrosion of course is the cause of this.

Engine is almost together. Will post photos soon

Jeff
The tstats are also different unless I'm mistaken

So if you get a newer housing, you need the newer tstat
Peter Florance
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JoshInAtlanta
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Post by JoshInAtlanta »

Peter Florance wrote:
Odometergears wrote:Thanks for the parts Christopher.

For the record, all you need is the cover. The difference between the housings are the number of holes you get for sensors. I have to plug a few. You will also need to get new bolts. Corrosion of course is the cause of this.

Engine is almost together. Will post photos soon

Jeff
The tstats are also different unless I'm mistaken

So if you get a newer housing, you need the newer tstat
Yep... I spent 45 minutes writing this up yesterday and then closed it thinking I posted...

The "A" style requires the later t-stat, the earlier housing uses the same t-stat as the late E12s.
1981 528i
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