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Hi guys.
Been out to the car this afternoon, screwed off the water filler cap and started the engine. Waited for a while to see what reading was coming up on the instrument clock and this stayed at 70 (bottom) for over 10 minutes. Felt the radiator hoses and top was hot whilst bottom was cold. I then squeezed bottom hose to try to release any locked air then revved car to 2500 for 10 secs or so and then repeated the bottom hose squeezing. Finally got dial to move from 70 to midway before it decided to drop back down to 70.
I am getting warm to hot air coming through the vents though.

Any ideas please.

Thermostat.
Haven't you already ordered one?

TRiBaL wrote:Thermostat.
Haven't you already ordered one?

Yep but was just making sure it was the thermostat and not the sensor.
Thermostat could be here tomorrow or Tuesday so that will be first job and with fingers crossed should solve the problem.

Update......................

Removed the 2 bolts holding the housing on and allowed water to drain before lifting out the old thermostat.
Removed the old "O" ring and fitted the new one only to find that the new one was slightly bigger, so checked the old one for damage and it seemed ok, so decided to use that again.
Fitted new thermostat into housing and tightened up the 2 bolts.
Filled water res to max level and turned on the ignition. Reading on temp clock 70.
Slowly revved up to 2500 and held it there for 20 seconds or so before getting out and pumping bottom hose to release air.
Top hose is now getting warm, bottom hose still cold. Continued this procedure 5 or 6 times.
Bottom hose is now almost as hot as the top one but temp gauge is still on 70. Another thing that's happened is the rev counter has now dropped to around 500 at idle (see photo 2 below).
I have just checked the new thermostat box and it is a 032 121 110B which is what I was told was right. However when I typed in the number on the box 100 616 755 on google it brings up the Hans Pries site and it says on there that this is for 87 degrees (see below photo). If this is the wrong thermostat would it make any difference to the temp gauge not reaching temp?

Just had a look at the old thermostat and that has 87c stamped on the bottom of it.

So does this mean that the 87c thermostats are wrong as I now have 2 that don't register on the clock or can there be something that I've missed?

That means your temperature sensor is also dead

Get it replaced.

87C is correct. The dial on the dash is also normalised, so until it gets to around 110, it wont move above 90C

Just been down to take out the sensor. Apparently there are 2 types, the "D" shaped plug or "square" plug.

This is mine but I can't find away to remove the plug from the sensor. Can someone help please.



and this is a "D" shaped plug on Ebay

You need to press the little tab in and wiggle the connector gently whilst removing it from the sensor at the same time

Thanks Alex. I'll give it a go tomorrow.

There's a slight chance that you haven't installed properly the thermostat. Before putting it in you have to push the needle against a wall or something just to make sure it is all the way in. Wasted one new thermostat because of this. Thought they sold me a faulty one and i threw it away because engine would never reach temperature above 70-75 degrees. A mechanic told me the trick and sorted it out.
But yeah, it's probably a sensor matter. If the new one doesn't fix this, then you know what to do.

TRiBaL wrote:There's a slight chance that you haven't installed properly the thermostat. Before putting it in you have to push the needle against a wall or something just to make sure it is all the way in. Wasted one new thermostat because of this. Thought they sold be a faulty one and threw it away because engine would never reach temperature above 70-75 degrees. A mechanic told me the trick and sorted it out.
But yeah, it's probably a sensor matter. If the new one doesn't fix this, then you know what to do.

Yeah!! Get him a Rover 414 like mine that I haven't spent a penny on in 12 months.

As for the thermostat. I did push the pin right in before installing it (read about that somewhere) and tested it first in boiling water. The pin came out about 20-25mm, so pushed it back in, installed it but still not getting a reading on the clock.
Going to order a new sensor tomorrow and see if that is the problem. Luckily all these little jobs so far haven't added up to much ....................YET

Just found this video on You Tube. Explains everything really clearly..........................

https://youtu.be/W0OxA11P_vk

Update........................

bought a brand new temp sensor this morning (VW part) £15 including VAT. Fitted it in, topped up the coolant and switched on the ignition. Started to squeeze bottom hose and release the air bubbles trapped. Then sat in the car watching temp gauge reaching mid way and staying there. Also notice the revs are now back to 750-800 where they should be. WOO HOO, looks like job sorted. Thanks guys, I've left a pint on the bar for you.