Replacing Thermostat - tips & how to do's

[Youdey]

I am replacing the thermostat on my 03 3.0 Z4. I was wondering if anyone had any tips or knows any videos that go through how to replace it. I've done a couple of small jobs myself so I am relatively inexperienced but I have decided to do it myself.

 

[Matty_Z4]

I’ve not got any videos but it’s pretty self explanatory once you have the new part in hand. 2x hose clips pull out the latch and slip off. One electrical connector and 3x bolts I think 2x 10mm and 1x 13mm

Just pulls out the front and the new one slips in.

Just don’t bleed the coolant like I did! Had heat on 100% and the fan on max (put the fan in low gets to temp quicker)

Watch the coolant temp when you’re bleeding and don’t let it boil or you will make a mess.

I used one of those bleeder funnels where you can put an extra 1l in the expansion tank and it burps the air out. However I let my coolant boil and you get lots of hot coolant splash everywhere.


Edit: if you watch E46 videos you will see how it’s done. Mine is an M54 so no electric water pump.

 

[enuff_zed]

Another tip is to have the front end up on ramps. Reduces fluid loss and makes it easier to bleed as well.
As you are in Cardiff, why don't you talk to [ref]colb[/ref] about meeting up with his Zedshed Cymru gang and doing it with them?
Yes, it's an easy job, but if it gives you more confidence having someone more experienced on hand..........

 

[Youdey]

I’ve not got any videos but it’s pretty self explanatory once you have the new part in hand. 2x hose clips pull out the latch and slip off. One electrical connector and 3x bolts I think 2x 10mm and 1x 13mm

Just pulls out the front and the new one slips in.

Just don’t bleed the coolant like I did! Had heat on 100% and the fan on max (put the fan in low gets to temp quicker)

Watch the coolant temp when you’re bleeding and don’t let it boil or you will make a mess.

I used one of those bleeder funnels where you can put an extra 1l in the expansion tank and it burps the air out. However I let my coolant boil and you get lots of hot coolant splash everywhere.


Edit: if you watch E46 videos you will see how it’s done. Mine is an M54 so no electric water pump.

Thanks

 

[Youdey]

Another tip is to have the front end up on ramps. Reduces fluid loss and makes it easier to bleed as well.
As you are in Cardiff, why don't you talk to [ref]colb[/ref] about meeting up with his Zedshed Cymru gang and doing it with them?
Yes, it's an easy job, but if it gives you more confidence having someone more experienced on hand..........

I would & have used colb's help in the past but he is 20/30 minutes away from me along a motorway, my car can only do 10 minute drives from cold & then 5 minutes at a time after that before overheating so I don't want to have to pull over all the time along a motorway.
Thanks for the tip

 

[enuff_zed]

Another tip is to have the front end up on ramps. Reduces fluid loss and makes it easier to bleed as well.
As you are in Cardiff, why don't you talk to [ref]colb[/ref] about meeting up with his Zedshed Cymru gang and doing it with them?
Yes, it's an easy job, but if it gives you more confidence having someone more experienced on hand..........

I would & have used colb's help in the past but he is 20/30 minutes away from me along a motorway, my car can only do 10 minute drives from cold & then 5 minutes at a time after that before overheating so I don't want to have to pull over all the time along a motorway.

Ah that's fair enough. Didn't realise it was actually having that much of a problem.

 

[raymond.harper]

https://www.youtube.com/watch?v=2eT1XMLV2dQ Is the water pump alright?

 

[enuff_zed]

https://www.youtube.com/watch?v=2eT1XMLV2dQ Is the water pump alright?

Easy check. Take the top off the expansion tank and see if you are getting a stream of water entering the top. If not then the issue could be the pump. Tbh, if it is then I'd change the thermostat at the same time.

 

[Youdey]

https://www.youtube.com/watch?v=2eT1XMLV2dQ Is the water pump alright?

Easy check. Take the top off the expansion tank and see if you are getting a stream of water entering the top. If not then the issue could be the pump. Tbh, if it is then I'd change the thermostat at the same time.

I've checked the waterpump & it does work. I did take it to the garage originally for them to fix the issue & they initially said it was the radiator but charged me £600!! This is just a normal garage btw not a specialist. It still didn't fix the issue so I had to take it back to them after getting stuck for 5 hours after it overheated again. I took it back to the same garage & they took it for a test run but obviously didn't listen to the car when the warning came up for the engine overheating & apparently came back with steam coming from the bonnet! It's overheated on me close to 10 times now but it has never had steam coming from the bonnet so they must've ignored the warning & carried on driving, I am now worried about the head gasket.

 

[raymond.harper]

Is the cooling fan coming on at all? Is there hot air coming from the heater? If you have an overheating engine you can switch the blower on hot at full speed to cool the engine. Also, a good code reader will live stream the temperature data to see what is going on.

 

[paddy wright]

It’s really easy- I have a video of when I did mine- will see if I can find it.

 

[Youdey]

Thanks everyone. I ended up chasing the garage up as I wasn't happy with the work they did & the fact they overharged me so they ended up fixing the issue for free.