Hi guys, just a quick few questions about the thermostat I'm hoping to use on my engine conversion.

Firstly, the outlet the finger is pointing to, where does that connect to?

And the two plugs on top, what do they do? This is going on a 1984 mk2 car with a later engine and the thermostat i had on before definitely didnt have these plugs so can i just not use them or what?

Thanks.

I can't help on the pipe, but those terminals are your temperature senders. One for the carb and one for the temperature guage.

You should have had them on the original thermostat housing, but they will have had different connectors and a large ruber boot that covers the plugs. If you still have the old thermostat, I'd simply swap to the early style senders if they were in working order.

I can't help on the pipe, but those terminals are your temperature senders. One for the carb and one for the temperature guage.

You should have had them on the original thermostat housing, but they will have had different connectors and a large ruber boot that covers the plugs. If you still have the old thermostat, I'd simply swap to the early style senders if they were in working order.

Thanks for the reply. Thinking about it, there was only one small connection on the top of the old thermostat but I'm sure that was it. It definitely will not fir these new plugs either so does that mean ill have to get one of these plugs and wire it in?

Thanks.

Anyone have any idea what this outlet is for?

its a for the heater I believe, I have the same stat housing for my 6n2.

Just use the two below it and blank that one off.

I'm not that keen on just blanking it off as it obviously went somewhere before. I don't think it for the heater. The diagram I've got seems to show one heater pipe going to the water rail and the other going to the outlet above the mystery one but its not 100% clear.

I've got an outlet on the water rail I don't know what to do with either. It's the one closest to the water pump. Just don't know where it goes..

it looks like it already has a blanking cap over the end of it to me. On several mk2 or mk3 polos they have at least one outlet blanked off.

None of the outlets have been blanked off, the tube I'm pointing to has a bit of cut off hose on the end but other than that they are all open.

Could be an idea though. The one I'm pointing to and the one above it merge into the same hole so maybe one was blanked off.

Still trying to discover where the outlet on the water rail closest to the pump leads to...

Later cars had the header tank breather pipe going to the thermostat rather than the top of the radiator. So it could be that..

On my now scrapped mk2 1990 Polo the black sensor was for the temperature gauge, and the brown one (red in your case) next to it switches a relay which controls the “hedgehog” heater element in the inlet manifold.

As far as I can make out from the manual that outlet pipe goes to the heater matrix inlet with the control valve. The other two go to the inlet manifold water jacket.

On the water pipe the outlet nearest the water pump goes to the automatic choke on the carb ( the return from the choke tees into one of the inlet manifold pipes). The middle outlet goes to the heater matrix and the next one goes to the bottom of the header tank.

Fantastic, thank you so much for that, you have saved me a lot of stress and headache!

One last thing though, as I'm using this housing on an older car which doesn't have the plugs to go into the sockets on the housing, what are my options?

Edited 23 August, 201115 yr by azza46

You could get some plugs from a loom off a later Mk2 from a breakers yard and wire them to your loom, or at least as a temporary measure you could use miniature spade connectors (3.7mm) which will fit the sensors.