Wiring M3 clocks into M42 FAO IAN332i

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Demlotcrew
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Post Thu Apr 28, 2005 9:55 am

Right people (Ian) what do i need to do in order to get the oil gauge to work on the m3 clocks?

I have also worked out that they are over reading by 100rpm which i can live with if anyone was wondering what they perform like on a four pot.

Andrew
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Post Thu Apr 28, 2005 3:12 pm

Demlotcrew wrote:Right people (Ian) what do i need to do in order to get the oil gauge to work on the m3 clocks?

I have also worked out that they are over reading by 100rpm which i can live with if anyone was wondering what they perform like on a four pot.

Andrew
Andrew,

It's actually quite easy to wire up the oil temp gauge. You only need three wires (power, GND and signal from the sender).

The biggest problem is finding somewhere to mount the sender. It's possible to use an E30 M3 oil temp sender as a sump plug. It's the same thread, and uses the same sized sealing washer. It is however down where it could get damaged. You could also use some sort of 'T' piece and fit it where the oil pressure gauge goes.

If you look at the back of the tacho, you should see three spade style connectors. One is marked as '+' , and one (I think) is marked 'G'. The other is not marked, but is the GND connection.

Simply connect the '+' to 12v (ignition switched), the terminal marked 'G' goes to the pin on the sender, and the last pin goes to GND. If you look at the official BMW wiring diagrams, they are actually wrong, and have the GND and 'G' terminal swapped. It won't work like this.

If you want to correct the tacho reading, you can use one of these:

http://www.dakotadigital.com/Detail.cfm ... mber=SGI-8

Cheers,

Ian.
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Demlotcrew
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Post Thu Apr 28, 2005 3:52 pm

Thanks Ian, well i have found that the late M30 oil filter caps have provisions for sensors to be fitted, but the ETK does not show this to be the case, but i have seen these with my own eyes.
Second problem is having it down as the sump plug will give inacurate readings surely? as the wind chill cools the sump down?
Where can i get a cheapo sender from? as BMW shows it to be Ԛ£20 and thats just a tad too much for me right now.

Also about the readout i think i can live with 100rpm, its very hard to notice anyway.

IS there a + on the clocks i can tap into?

Thanks

Andrew
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Post Thu Apr 28, 2005 3:58 pm

I don't think wind on the sump will cool the oil in the sump!

It's great that you can plug a sensor in there! Shame it's a bit of a dodgy place to have it!

:)
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ian332isport
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Post Thu Apr 28, 2005 4:55 pm

Demlotcrew wrote:Thanks Ian, well i have found that the late M30 oil filter caps have provisions for sensors to be fitted, but the ETK does not show this to be the case, but i have seen these with my own eyes.
Second problem is having it down as the sump plug will give inacurate readings surely? as the wind chill cools the sump down?
Where can i get a cheapo sender from? as BMW shows it to be Ԛ£20 and thats just a tad too much for me right now.

Also about the readout i think i can live with 100rpm, its very hard to notice anyway.

IS there a + on the clocks i can tap into?

Thanks

Andrew
Not sure about the oil filter cap. Would be a nice, neat & easy installation if you can find one.

I think Adam has used the M3 sender as a sump plug, and is not experiencing any problems with the temperature. I believe his reads pretty much the same as mine.

Not sure about a cheapo sender. You may be able to find one, but it probably won't read the same as the M3 one. It all depends on the resistance of the sender at different temperatures.

There's several +ve wires on the clocks. I would use the same supply that runs the other temp gauges. This comes from fuse 10, and is the same supply that is used on the M3. It can be found on pin 23 of the blue connector, or pin 6 of the white connector. Both wires should be green/white.

Cheers,

Ian.
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Demlotcrew
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Post Thu Apr 28, 2005 5:07 pm

Okay well, i dont have most of the parts anyway so i might as well save for the proper BMW one.

Dave it must cool it a bit???


Thanks Ian


Andrew
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Post Thu Apr 28, 2005 5:14 pm

I'd like to get these clock one day...

There isn't a direct flow of wind onto the sump, but even if there was, do you think it would cool the oil? Even 1 degC?

:?
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Demlotcrew
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Post Thu Apr 28, 2005 5:20 pm

Yeah i do, even by 10 deg if not more.

Andrew
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Post Thu Apr 28, 2005 5:22 pm

Ian?

:lol:

I can't imagine the heat of the oil, which is constantly flowing round the very hot engine being cooled by a bit of wind...

I'm fully willing to accept if I'm wrong, just doesn't seem possible to me... 8O
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Post Thu Apr 28, 2005 5:25 pm

my temp sender is in place of the sump plug and reads same as adams also.
When i take the sump off though to fit my turbo return pipe i think i will drill another hole for it so it is slightly higher, although ive never had a risk of it been knocked off.

At idle you will notice the tach is slightly out but by the time mine reads 8000 rpm its obviously only doing 7000 rpm.So the further up the scale it gets the further out it will become.Yours may be ok though ,dont IS engines rev higher than 6 pot m20's anyway so it maybe ok as it gets round to 8000 rpm
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Post Thu Apr 28, 2005 5:32 pm

buster wrote:obviously only doing 7000 rpm
:eek:

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Demlotcrew
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Post Thu Apr 28, 2005 5:44 pm

Well the chip i have is limited to 6900, and on the clocks the needle bounces around the 7k mark when i hit the limiter so i think its rather acurate. Im ussing the M3 coding plug.

Andrew
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Post Thu Apr 28, 2005 6:33 pm

oh well thats good then,nice one.I had to use the 6 cylinder coding plug as you know,e30m3 only 4 pot so with the m3 plug it was miles out.
Simon
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Post Thu Apr 28, 2005 8:29 pm

The sump is designed to cool the oil slightly that's why it has the fins in it, just like the diff, how much of a difference it makes though is anyone's guess.
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Simon13
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Post Thu Apr 28, 2005 8:40 pm

the fins cannot cool that much, because why do 325's have oil cooler pipes?!
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Post Thu Apr 28, 2005 8:45 pm

Simon13 wrote:the fins cannot cool that much, because why do 325's have oil cooler pipes?!
Like I said above, they don't cool the oil by a considerable amount, but it all helps with keeping things cool.

Maybe the fins are there to look good when the car is on a ramps!!? :mad: :lol:
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Post Thu Apr 28, 2005 8:52 pm

Mine doesn't have 'fins'

:cry: :cry: :cry: :cry:

:mad:
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