M10B18? Coolant bypass hose

[damers2000]

Hi all,

Firstly, my car is a 318i 1988 reg so hopefully have the engine type correct in the heading.

Just having a look around the engine bay and what I thought was a poorly put together replacement hose appears to have been put in to bypass something. I have been advised that it could be there to bypass the preheater but could anyone shed any light on this for in terms of where the hose should go, what that side of the engine should look like as standard etc. I am not a mechanic or familiar with the engine so in the dark.

[30316]

That bypass hose arrangement is unusual. Can’t see from your pictures where the hose under the inlet manifold is connected but I am assuming it goes to the heater near the bulkhead.

I can only think a previous owner has had problems with the heating in the car and has taken the feed near the thermostat and not from the cylinder head. As a first step I would consider putting back to standard and see what does not work.

[damers2000]

I think that's the only thing I can do. The engine is being taken out while it's in bodyshop so I'll get it all sorted then fingers crossed. Its turning into quite an expensive project but hopefully be worth it in long run