Are you sure the cooling system was bled correctly when refilling?
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Are you sure the cooling system was bled correctly when refilling?
Yeah we had the bleed screw out of the top of the radiator and filled it up with the hose. When it was about full we started it and kept the water going through as it pumped.
We bled it again after removing the thermostat.
One lesson I learned from Blknight was not to use 12 pt sockets on big jobs like that... A 6pt impact socket is a "must" to minimise the chances of bolt rounded heads etc and stuffed tools... glad you got it sorted!
I have it all back together now, On sunday afternoon we had some issues with the temperature. The temp gauge would rise very quickly to the gap before it hits red. The radiator hoses and water in the radiator were cool and the heater hose got very hot.
We earthed the sensor wire and the gauge moved right to the limit of hot.
So we took the thermostat out to see if that was the problem blocking the radiator. This held the temperature down at idle so i went for a test drive and within 500m the gauge was in the red. I pulled over sharpish and the could still touch all of the hoses. They were warm but no overly hot. It hadnt been running long enough for it to get up to temp under normal circumstances.
Through all of this i could still stop the viscous fan relatively easily.
I put a new temp sender in and a new thermostat and it is doing the same thing. I had the engine running and eased the hose off the thermostat housing and water shot out with reasonable pressure. Is there another way to check the gauge to make sure its okay or does it sound like the water pump could be the problem?
I bled the system by taking the bung out of the radiator and filling til water came out then topping up the reserve tank.
Cheers,
Joe
Hi Joe,
I'm no expert, but if the heater hoses are hot (coolant directly from cylinder head) and the temp gauge has been tested and also shows hot, I would be careful you're not damaging the head gasket. It also says there is definitely a coolant flow issue.
Did you fill via the bung on top of the thermostat housing? Or just the radiator? The thermostat housing is the highest point that air can go, however it can also get caught in the heater matrix.
If you remove the thermostat housing bung, does coolant immediately flow out? (Engine off - careful, could be pressurised if engine has been running). If coolant doesn't flow out, I would say you still have air in the system.
When I re-filled mine, the last place I filled was the thermostat housing as it's the highest.
- Justin
I will try that then. I don't have a bung on top of my thermostat housing. Ill have a play with some jacks and sort the highest point that way I think.
The heater lines aren't connected so might try a way to bleed from there.
Cheers,
Joe
:confused: I've never heard of that. You don't have a brass plug or black plastic plug like in this photo? (Borrowed photo from another forum. :angel: )Quote:
Originally Posted by blue_mini
https://www.aulro.com/afvb/images/im...012/11/437.jpg
Not connected? Are they piped together at the back of the engine block?Quote:
Originally Posted by blue_mini
Mine is a 200tdi, the cooling system has 2 places to put a bung but I need to drill and tap them.
I'm confident that the engine isn't overheating now. Having a look at the gauge wiring next to try and figure out a problem there.
And my heater has been bypassed with a hose out and straight back in.
Ohhh sorry. I keep assuming everything is a 300TDI. :D