Early / Late pre-facelift differences + Cooling

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bebus
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Post Tue Nov 08, 2016 10:26 pm

Just bought myself a 325i (Feb 1987):

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The car needs quite a few things done, but seems ok on the whole.

Looking at the engine bay, I noticed some differences to a friend's 325i, for example the different setup for the expansion tank.

Mine:
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Other 325i (1988)
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I read up somewhere that the setup was changed sometime around July 1987. Are there any other major differences between the earlier and later pre-facelift models?

Also, it seems that the levelling switch was disconnected for whatever reason, whilst the wires to reconnect them are too short, so I think something else has been removed with a chunk of the wire too, but I couldn't find any info.

Image

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Maybe someone has a better idea what exactly is missing?

Thanks!
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Brianmoooore
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Post Wed Nov 09, 2016 12:30 am

Not everything changed at exactly the same time, but the main difference between the early and later engines is that the earlier engine has a higher compression ratio than the later, but any advantage that this might give is negated by the more primitive engine management electronics.
As for the cooling system, the earlier system, with the tank on the RH side uses a different water pump on the engine, with a stub pipe on it to connect to the tank. which isn't present on the later pump.
If the wires to the coolant level sensor are simply disconnected, the warning LED should be lit.
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Carmo13
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Post Thu Nov 10, 2016 12:36 pm

Interesting to see you have what looks like an auto choke or something connecting to the throttle body from the box of tricks on the left hand side of the engine bay.
I have an 87 and it doesnt have that?
Cloggy Saint
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Post Thu Nov 10, 2016 12:45 pm

That's the cruise control cable.
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bebus
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Post Sun Nov 13, 2016 9:46 pm

Thanks for the info!