Hi guys

I am trying to do a radiator and coolant flush on a recently bought 1989 740 Turbo sedan (RHD).

One of the things I'm looking to replace is the thermostat. From what I have read through searching the RWD forum, the upper radiator hose should connect directly to the thermostat housing. Now I don't happen to have a diagram of the cooling system handy.

So, can someone kindly tell me where the thermostat housing is in this picture of my engine compartment?

Look as I may but I simply cannot see it. The upper radiator hose hooks up straight into the engine block as it seems!

The state of the coolant as visible in the reservoir tank should explain why I am keen to get the cooling system flushed! :-) The stuff in the reservoir is rust brown and I already have a flushing chemical in there for the last few days which I am keen to flush out completely.

FWIW, I have learnt that the coolant drain cock for the engine in this turbo car is NOT near where the oil cooler is behind the oil filter (unlike what's described for a 940T in the FAQ). It's actually on the block above the oil filter in an incredibly inconvenient location. Like that described for a NA B230 engine - but unlike which, I cannot access from the top since the turbo unit and the heated air contraption that bolts on to the top of the exhaust downpipe completely prevents reaching it from the top.

Thanks

Lucast

Look at the white paper label at the front of the engine in the photo.
Now look straight to the right to where the hose meets the engine.

The hose attaches to the thermostat housing. The t'stat housing is attached to the head with two nuts.

I strongly recommend some PB Blaster to loosen up the threads on the two nuts before loosening. Reason is, they often are on there for many years and will get rusty. I loosened one once without using PB Blaster and broke the stud that the nut is threaded onto. I was lucky; there was just enough stud left for me to thread the nut back on. But now I never open up one of those without using PB Blaster first, unless it's one I've had open myself in recent memory.
--
Sven: '89 245 NA, 951 ECU, expanded air dam to 7" from ground, forward belly pan reaches oem belly pan, open-front airbox, E-fan, 205/65-15's, IPD sways, E-Codes, amber front corner reflectors, quad horns, tach, small clock. Wifemobile '89 245 NA stock.

Thanks Sven, that's most helpful mate!

I use some sensor safe silicon on the two mating surfaces. Carefully tightening, soft aluminum, you can twist the studs off very easy.
--
Post Back. That's whats makes this forum work.