Coolant hose plumbing

[Grrrmachine]

It's times like this that I feel very dim

Putting all the rubber hoses back onto the car, and I seem to have too many pipes. The rad, overflow tank, water pump and thermostat are all connected, and the throttle body heater is plumbed in.

Now I've got the pipe from the back of the block that goes to a metal T-piece with two exits (long and short, with the short one going to the heater matrix).

And I've got a long hose from the thermostat with a plastic T-piece, and a long and short out. Am I right in thinking the metal T-piece connects to the plastic T-piece? And which short hose goes to which heater matrix pipe?

Engine's a facelift M20.

[Grrrmachine]

As an extra; I wonder if this plumbing has anything to do with the "optional water pump" that I see mentioned in RealOEM. I can't find anyone else talking about metal or plastic T-pieces in the archives, and yet both my original M20 and the E34's donor M20B25 came with these sorts of coolant pipes.

[b12rlw]

Hose from the back of the head (sort of s shape) goes to the top matrix port. Bottom matrix port to the bottom of the stat and header tank. Take a look on real oem for the diagrams. Would post them but im using my tablet. My high comp engine didnt use tees. Youve got the hose from the block going to the stat too? Hope this helps, real oem will.

[b12rlw]

The option pump, id guess, is the two port effort for the high comp engine.

[Grrrmachine]

Yeah, I found out which hose goes to which pipe for the heater. But both hoses have a t-piece included; one plastic, one metal, and then I think these are joined together, effectively creating a heater bypass.

It's definitely BMW and not an aftermarket bodge, but I don't see the purpose of it.

[Brianmoooore]

Hose from the back of the head (sort of s shape) goes to the top matrix port.

Hose from the back of the head goes to the BOTTOM matrix port.

The '96 (?) recall may hold the answer to some of your questions. In the UK we just got a replacement pressure cap for the header tank, but in the US there was some sort of bypass arrangement across the heater hoses.

[Grrrmachine]

LPG! Two t-pieces cut into each of the heater hoses, that sounds like a textbook gas installation, doesn't it?

[Brianmoooore]

LPG! Two t-pieces cut into each of the heater hoses, that sounds like a textbook gas installation, doesn't it?

If you have LPG on this, then that's what it is.

[Grrrmachine]

The car had it when I got it, but no idea about the donor engine, which has identical T-pieces in identical places. So either there's a standard kit and I've got lucky, or there's something else afoot.

But since I can't find ANY reference to this plumbing on RealOEM or bmwfans, or on any other forums, I'll have to assume it's a bodge and therefore bypass it.

[Brianmoooore]

This is the recall mod. to which I was referring, but yours is probably LPG connections, considering you're in Poland.
http://www.justanswer.com/bmw/24me7-199 ... valve.html