524td auto to 535i std swap info?

General conversations about BMW E28s and the people who own them.
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Spaz!
Posts: 77
Joined: Jan 13, 2014 3:40 AM
Location: Moriarty, NM

524td auto to 535i std swap info?

Post by Spaz! »

Hi all,
I recently bought a very decrepit and rusty 535i and would like to swap it into a very nice 524td chassis I bought yesterday. I'm wondering what issues may come up along the way?
I expect some of the harness will need to be swapped over and obviously the pedal box along with the entire power train. What else was different between the two?

I'm basically doing the m30b35 / motronic 1.3 swap which is well documented except when going into a TD chassis. plus the fun of an auto to manual and brake/suspension swap! How do I talk myself into these things?

Both cars are '85 models so hopefully that will save me some headaches, still cant believe I was lucky enough to find a clean body right around the corner!

Any info will be greatly appreciated!
Last edited by Spaz! on Jan 10, 2021 10:51 PM, edited 1 time in total.
Mike W.
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Joined: Feb 12, 2006 12:00 PM
Location: California Whine Country

Re: 524td auto to 535i std swap info?

Post by Mike W. »

I helped on one of these. I was late to the show but had to figure out why things weren't working right. It turns out the engine harness connector that plugs into C101 I think it is, the one on the side of the fusebox, was different. The fusebox itself is different. The plug will plug in, but it's different size wires running to different places. It wasn't my car, I was just helping a friend try to make it right, so I didn't have all the pieces. In retrospect I think I'd have swapped fuseboxes. Seems like the O2 sensor heater relay was also a bit of a challenge, in part because of the td fusebox and wiring. There are a couple of wires that connect in the middle, at the main relay IIRC, but really it's a motronic harness for the ignition and FI, and a separate engine harness for alternator, oil pressure, water temp etc. Input to the coil of the main relay might have also been an issue.

This was one day ~10 years ago so forgive me on a lack of detail.
Spaz!
Posts: 77
Joined: Jan 13, 2014 3:40 AM
Location: Moriarty, NM

Re: 524td auto to 535i std swap info?

Post by Spaz! »

Thank you, Mike! Every little bit counts in the long run. there is a lot of info on swapping the baby 6 out for a big 6, but not much for the TD cars.
a
Posts: 12469
Joined: Feb 12, 2006 12:00 PM
Location: Marshfield ,MA

Re: 524td auto to 535i std swap info?

Post by a »

Please post progress I have a good 533i I want to turn into a super eta :cool:
Spaz!
Posts: 77
Joined: Jan 13, 2014 3:40 AM
Location: Moriarty, NM

Re: 524td auto to 535i std swap info?

Post by Spaz! »

Ill keep you posted A. Im researching all the finer details now and hunting parts. If youre going to a baby 6 engine I have an m20b25 and matching 5spd from my '87 325is, an eta block with rotating assembly and now the m21d24 from the 524 td that all need new homes. Id be willing to make someone a heck of a deal on them if they would take them as a package!
tn535i
Posts: 5585
Joined: Jul 14, 2006 1:30 PM
Location: Middle Tennessee

Re: 524td auto to 535i std swap info?

Post by tn535i »

IF you don't already know it and it addresses the C101... The ETM at wedophones will be your guide to all things electrical. You will have some pages of it memorized before you are done.
Spaz!
Posts: 77
Joined: Jan 13, 2014 3:40 AM
Location: Moriarty, NM

Re: 524td auto to 535i std swap info?

Post by Spaz! »

Thank you Tn535i, I saw it mentioned in the B35 swap FAQ but I haven't been over to look at it yet.
You don't happen to know if an auto trans harness from 88-89 535i will work for a manual car swap do you? From what I've read I think I will need the auto TPS and I'm good to go but I'm not sure.
tn535i
Posts: 5585
Joined: Jul 14, 2006 1:30 PM
Location: Middle Tennessee

Re: 524td auto to 535i std swap info?

Post by tn535i »

I believe the auto harness will work fine. BMW's harnesses had 'optional' stuff that was used or not. Again the ETM breaks all these things out for you.

From memory... defeat the PN relay, if an EH trans TPS you want to return to the basic TPS and follow ETM to get proper connections to the DME, I think there is a pin on the DME you also ground that was a PN input. There may be others but might be that simple. My son and I did an e30 and it was a piece of cake... of course no EH trans and no CC. So if you have CC you need to ADD the clutch switch to break that.

If you run into something I'm sure experienced people here will know.
Spaz!
Posts: 77
Joined: Jan 13, 2014 3:40 AM
Location: Moriarty, NM

Re: 524td auto to 535i std swap info?

Post by Spaz! »

Thanks TN 535i downloaded the etm and have been looking it over. I've decided to get the TD running for now as I'm pretty sure fuel prices are about to go through the roof but once it's up on its maintenance I'll be back at the 535 so I can get everything sorted out in that chassis before swapping it to the 524.
gadget73
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Joined: Nov 22, 2017 10:30 PM
Location: New Jersey

Re: 524td auto to 535i std swap info?

Post by gadget73 »

Diesel is more spendy, so just make sure you consider that. Regularly 40c/gallon more in NJ. The fuel mileage does make it cheaper per mile, but consider 2 gallons of oil and a not very cheap oil filter every 5k miles and you may find its not as cheaper as you expect.
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