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Old 14th December 2019, 17:25   #11
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Old 19th December 2019, 10:05   #12
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Driving to Leominster near Hereford tomorrow afternoon!


I've been looking at the antifreze threads and I see that my coolant is a rust colour! Does that mean it's pink OAT?


Help. I plan to take a 5 litre container of coolant mix and want to have the right stuff. Might take a proprietory leak sealer with me as well. Don't really want the ignomony of being rescued.



Well, garage replaced the entire thermostat housing. They commented that the metal pipe didn't appear to enter fully into the housing and that they used 2 seals. They'd wanted to replace the pipe but no stock. I can't think why this should be happening.



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Old 19th December 2019, 12:19   #13
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Well, garage replaced the entire thermostat housing. They commented that the metal pipe didn't appear to enter fully into the housing and that they used 2 seals. They'd wanted to replace the pipe but no stock. I can't think why this should be happening.

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Likely the bracket that holds the pipe in the stat housing has been bent by being forced out of the thermostat housing at some point - the stat should be unbolted before removing the pipe.

Easy enough to spot it with the pipe out of the stat. It can be straightened by clamping a pair of mole grips on it and carefully bending it back.
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Old 19th December 2019, 17:46   #14
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I think my fan isn't working. I'll do the demist test when I come back from Leominster (see end of post) and have read other threads on this topic.


Went for a run back end of afternoon and thanks to the useful T-Cut's How To post had the OBD on the dash running. Build up to 88C and then a sudden jump up to 114C drop back down to 88C. Things got very erratic, mind you I was in the dales and at one point romping up a 1 in 5 in third gear.


Basically variation between 90C and 112/114C.


When I parked up on return to village 102C and while idling went round the front and fan stationary. Hoses very hot but is was pouring with rain and didn't scarbble around for the bottom hose. Radiator itself didn't feel hot on the fins.


Thankfully no leakage from the second thermo housing to pipe connection.


I'll check the coolant level tomorrow after overnight stand so it's properly cold.


Anyhow, I think it's the SEAT to Leominster. DAMN.


That temp gauge needle is pointless.


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Old 20th December 2019, 13:32   #15
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I see that my coolant is a rust colour! Does that mean it's pink OAT?
OAT antifreeze is (usually) red or pink or orange in colour according to the manufacturer. Coolant should also be clear. By that I mean see-through like tap water, but coloured. If it's cloudy it needs replacing. See your Haynes manual for doing this.


Quote:
Might take a proprietory leak sealer with me as well. Don't really want the ignomony of being rescued.
No don't. Get rescued if necessary.


Quote:
I think my fan isn't working. I'll do the demist test when I come back from Leominster (see end of post) and have read other threads on this topic.
It's a simple five minute job. You need to know before a long drive not after.


Quote:
Build up to 88C and then a sudden jump up to 114C drop back down to 88C. Things got very erratic, mind you I was in the dales and at one point romping up a 1 in 5 in third gear. Basically variation between 90C and 112/114C.
Fir a cool running diesel that only means one thing, insufficient coolant is circulating. In other words, it's got air in the system. You need to top up and bleed as described in Haynes before doing a long trip.


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When I parked up on return to village 102C and while idling went round the front and fan stationary. Hoses very hot but is was pouring with rain and didn't scarbble around for the bottom hose. Radiator itself didn't feel hot on the fins.
Which again indicates the low speed fan isn't working (ref Demist Test) and there's not enough coolant in there.

ADD: For a diesel at this time of year, a full and air-free cooling system is actually more important than a functioning fan. Especially if you have to travel but little time to prepare. Many diesel owners drive around for years not realising their fan doesn't work. A dodgy aircon output is the usual sign. For low coolant, it's usually poor cab heating. Overheating to 114C suggests you have way too little.


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Old 21st December 2019, 17:09   #16
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Doing this on the 'phone but thanks a lot for your comprehensive response. I took the Alhambra on the the trip (away now) and the flooding is substantial here. I'm not sure the lower ride 75 would have managed.

I'll follow you advice as soon as home. Off to Scotland Boxing Day.


Home and not done demist check yet but forgot to mention that it's a Kenlowe fan (although that shouldn't really make a difference...................).


Thanks again.


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Old 24th December 2019, 09:42   #17
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UPDATE - First of all thanks to T-Cut for his input and Jules for the fan threads.



Followed Haynes manual and bled system. No real change on run out. Actually looked at the dial gauge (not just the trip meter section 19 subsection 7 readout which was at 115). Needle got to just past 11 o'clock. The odd thing is I pulled over, stopped for no more than 3-5 minutes, restarted and needle at 9 (although I forgot to re-instate the OBD) mile or two down the road and needle on the way back up - should've reinstated the OBD. This happened twice. Can only have covered 15- 20 miles overall.



It's a new thermo or I'd think it was stuck shut although the top hose is hot. I've left it overnight and will check the coolant level when the awaited delivery van arrives and I can get out of the house.


I think I'll have to drop the coolant and try flushing the block and rad as per Haynes. The only problem being lack of access to a hosepipe. I can only think that there's a persistent airlock or a blockage. Just have to do one thing at a time. Garage think I'm making a fuss and it's just Rover electrics and probably a faulty sender.


By the way the heater blows cold and also failed the demist test. But as you say, it shouldn't heat up that fast anyway and plan to sort that first and move on from there.



Away to Scotland Boxing Day, probably in the Alhambra. It takes that at least 10 miles to get up to temp if not longer (also a diesel). Thing is the 75 engine is up to 167k, over 70k mine, and sounds better than the Alhambra which is at 98k, of which 31k mine!


Thanks for your interest.


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Old 24th December 2019, 09:51   #18
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You have an airlock somewhere, don’t worry about a non working fan the diesel will not overheat even in traffic when the coolant system is bled properly.




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Old 24th December 2019, 16:19   #19
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FINAL (hopefully) UPDATE - Needed to add about a litre to the expansion tank. ignition on, OBD on the trip meter and away. About 26 miles and at 60mph steady speed there was slight movement between 87C and 92C except under firm acceleration which gave rises above this but with immediate drop once at new speed. Hot air for feet (my side) but passenger side always been poor, I'll have to check the pipework one day.


So it looks like there was a noticeable airlock.


The only odd thing was that when I parked up I switched off and sat being happy for 4-5 minutes thinking a nice ride to Scotland then after all. For some reason I put the OBD going again and fired up remaining parked. Not surprisingly the temp was up a bit at 94C but the heater air was cold. Switch off, start up again without the OBD going and heater air warm. Same cycle 2/3 times. OBD on, cold air. OBD off and hot air. Quite odd.



I'm wondering if the new thermostat is lazy. Wish I'd gone for the in line job that at least is relatively easy to do something with. I'll check the coolant position tomorrow and make a precautionary dip of the oil but I think the system is secure as there is some very faint residual pressure when removing the cap.


Thanks for all the support and guidance. I'll use Jules' guidance notes and do a proper test of the fan at the trinary(?) switch to see if it still motors. I take the advice offered but the fan's there and I want it working as soon as I can.


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Old 24th December 2019, 22:17   #20
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So it looks like there was a noticeable airlock.


JohnnyBG

These diesels usually self bleed when filling - the only time I have seen a problem is if the small pipe going in to the top of the expansion tank gets blocked.

You can check it by removing the expansion tank cap and running the engine at idle. You should see coolant seeping back into the top of the tank.
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