M50 First Start Questions

[Blitzer418]

Hey guys,
I'm swapping an M50 engine into my Triumph TR6, and I'm very close to starting the engine for the first time. The Engine is mounted, external fuel pump is mounted, exhaust is hooked up, and now I just need to mount the alternator. I do have a few questions:

- I've got the O2 sensor hooked up only from one exhaust manifold output (cylinders 1-3), just because it made it waay easier to fabricate the exhaust. From my research, OBD1 doesn't even warn you with an engine light when the mixture is off... so would it matter?

-I also need to figure out how to simply wire the harness to start. I know that there is a starter wire, and an ignition wire... Can I send 12v through those wires to start the engine? Anyone know if fuses are hooked up to those wires?

Any input would be just be fantastic. Thanks guys,

-Addy

EDIT: wow that picture looks TERRIBLE when its reduced to 115kb

[M3PO]

It's not ideal to have the sensor only reading 3 cylinders but it should be fine. There are CEL codes related to mixture issues though.

[Sea Aych]

Re: the O2 sensor, i've had it on only one of my headers in my swap car for over 20,000km without issue - you'll be fine. It may be very slightly off an optimal mix, but i haven't noticed deviation from what I expect the fuel mileage to be!

As for the wires, I know on my car there's 12v going to the starter straight from the battery through the fusible link in the e30 trunk, but i'm unsure of the fuse situation otherwise, especially for powering the fusebox. Ill look it up and post an edit

AWESOME swap by the way! Definitely do a big writeup if you haven't already!

If you ever want a hand with this stuff give me a shout - i'm pretty close to you i think

====
Edit: in my case I used the standard e30 starter, meaning it was mated to the e30 flywheel and the getrag 260. In that case, I had the black cable from the alternator and the body-side battery cable going to the starter. I did it this way so that i could remove the starter wiring from the M50 harness and just use the chassis' wiring (since it was easier to wire the fusebox, etc.). In that case, the wires i removed from the M50 harness were the two cables that split off a thicker red cable inside the wiring harness plastic box thing.

Alternatively, if you want to keep the M50 harness intact, the single end of the split cable goes towards the battery, and for the split end: the thicker cable goes to the starter, and the thinner goes to the fusebox. After that, the alternator cable will also have to go the starter. If you already have your fusebox wired, just run both the thick and the thin to the starter.

To get the car to start at a minimum I think all you need is ignition, fuel pump, starter, and of course ground... i may be wrong on that though

[arch4ngel]

Nice swap!
The M50 should do nicely in that tiny car.

I would highly recommend going over the wiring diagrams here:

http://wedophones.com/BMWManualsLead.htm

I'm not familiar with OBD1 so can't help with the specifics but that should give you everything you need to trace out the starter wiring and all other engine systems.

Not sure if m50s came equipped with EWS, but you may have to deal with that as well.

Best of luck.

[M3PO]

The M50 harness is really simple. Just provide it power in a few places and it only needs a few wires to run.

[Sea Aych]

Nice swap!
The M50 should do nicely in that tiny car.

I would highly recommend going over the wiring diagrams here:

http://wedophones.com/BMWManualsLead.htm

I'm not familiar with OBD1 so can't help with the specifics but that should give you everything you need to trace out the starter wiring and all other engine systems.

Not sure if m50s came equipped with EWS, but you may have to deal with that as well.

Best of luck.

No EWS on the non-vanos - no finicky business!

[Blitzer418]

It's not ideal to have the sensor only reading 3 cylinders but it should be fine. There are CEL codes related to mixture issues though.

oops, I guess I was incorrect. Good to know though, for now I'll only have it hooked up to one manifold output.

Re: the O2 sensor, i've had it on only one of my headers in my swap car for over 20,000km without issue - you'll be fine. It may be very slightly off an optimal mix, but i haven't noticed deviation from what I expect the fuel mileage to be!

As for the wires, I know on my car there's 12v going to the starter straight from the battery through the fusible link in the e30 trunk, but i'm unsure of the fuse situation otherwise, especially for powering the fusebox. Ill look it up and post an edit

AWESOME swap by the way! Definitely do a big writeup if you haven't already!

If you ever want a hand with this stuff give me a shout - i'm pretty close to you i think

Hey thanks for the kind words man! Good to know that the O2 sensor should work fine with only 3 cylinders.
As for the starter, the power to the starter is all hooked up - i just need to find a way to activate the switch through the body connector. Looking at this site:

http://garagistic.com/index.php?page=e30-m50-swap-wiring

it SHOULD be pretty simple. Also thanks for the offer to help, I may need it :)

Nice swap!
The M50 should do nicely in that tiny car.

I would highly recommend going over the wiring diagrams here:

http://wedophones.com/BMWManualsLead.htm

I'm not familiar with OBD1 so can't help with the specifics but that should give you everything you need to trace out the starter wiring and all other engine systems.

Not sure if m50s came equipped with EWS, but you may have to deal with that as well.

Best of luck.

Maybe its just me, but going over those BMW electrical pdfs is like reading gibberish. But that being said, I think I've found the two wires I need to hook up from that Garagistic link (green for ignition, black and yellow for starter)

[RainRider]

Sorry I'm not adding to this. Love to see more pics of your build. TR6!

[Blitzer418]

Okay I've got a few more questions... I've attached a few pictures.
-There is a hose fitting that isn't hooked up under the throttle body, whats this for? Its the nipple to the right in the picture.
-There is also another attachment with what looks like a copper end to it, where does this go and what is it for? I'm assuming it plugs into the 90 degree intake piece, i've attached a picture of it. BUT, it doesn't seem to fit... am I missing something? Also note the cracks...

Also just sharing what I did for the belt system.. Since the TR6 has no power steering, I needed to get a shorter belt. Getting rid of the tensioner that attaches to the alternator, a 55 3/4" belt fits PERFECTLY! I still need to make a bracket to raise the bottom of the alternator that clears the steering column.. But that spring tensioner gives the pulley a good amount of wiggle room.

[Sea Aych]

Okay I've got a few more questions... I've attached a few pictures.
-There is a hose fitting that isn't hooked up under the throttle body, whats this for? Its the nipple to the right in the picture.
-There is also another attachment with what looks like a copper end to it, where does this go and what is it for? I'm assuming it plugs into the 90 degree intake piece, i've attached a picture of it. BUT, it doesn't seem to fit... am I missing something? Also note the cracks...

Also just sharing what I did for the belt system.. Since the TR6 has no power steering, I needed to get a shorter belt. Getting rid of the tensioner that attaches to the alternator, a 55 3/4" belt fits PERFECTLY! I still need to make a bracket to raise the bottom of the alternator that clears the steering column.. But that spring tensioner gives the pulley a good amount of wiggle room.

For that copper thing - it's a thermostat for the throttle body coolant/heating lines to keep it from freezing up in the winter.. It's supposed to go into the E36's airbox to sense temperature. AFter '95 they got rid of it. You can either take it out and get both lines to go together, bypassing the sensor, or just remove the hoses entirely and plug the block somehow.

Unless you're driving in insanely cold weather and need to keep your throttle body from freezing up, just bypass it. I removed mine since it was cracked anyway.

[M3PO]

On the thottle body, there are heater/water connections and a vacuum port for the charcoal canister. You can delete all of the throttle body heater stuff.

[Blitzer418]

On the thottle body, there are heater/water connections and a vacuum port for the charcoal canister. You can delete all of the throttle body heater stuff.

Thanks for the info guys, I think I've got everything together except the wiring...
Does anybody know if the ignition wires should have a fuse? Looking over the fuse chart for the 325i, it doesn't seem to list anything for ignition.

[Blitzer418]

Well today was a great day! The engine fires right up, and I'm very happy. Just wanted to say thanks for everyone thats been helping me out, I'll post a video of the engine running. Thanks again everyone!

https://www.youtube.com/watch?v=OPNZ9fKKQIs

[M3PO]

Congrats! Told you it was easy to get these engines going! That little car is gonna rip with that engine in it.

I am a little concerned about that tiny radiator though. These engines need good cooling, they are known for cracked heads.