Help with Cooling

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RKB
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Post Fri Aug 07, 2020 7:49 pm

Running into problems with my cooling.

I've replaced all hoses, radiator and thermostat and it's been bled.

Now when I drive the temp increases to over halfway when doing 60 plus.

I've found when I park up after a long drive today, it pissed it's coolant, I couldn't tell where it was coming from but I've just done the same journey (having replaced the rad cap) no coolant loss however the temp kept creeping to the mark above half.

Any ideas?
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flybynite
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Post Fri Aug 07, 2020 8:03 pm

If it is the one with the built in header tank, have you bled it properly?

I don't think they can be bled unless the nose is quite high. Much easier with the standard tank.
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RKB
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Post Fri Aug 07, 2020 8:26 pm

It's the E36 Aircon rad? So like a sleeve alongside the rad?

I've seen that the car needs to be in the air in order to bleed it fully but I've tried and failed.

May get someone else to do it.

Would i, if I were to do it just lift the front and keep topping up the fluid with the bleed nipple open?
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Brianmoooore
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Post Sat Aug 08, 2020 12:00 am

What engine? What car?
No mention of checking/replacing water pump.
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RKB
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Post Sat Aug 08, 2020 12:28 am

M52 converted e30

Not sure on the water pump will have to rummage through my receipts to see if its been changed.
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Brianmoooore
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Post Sat Aug 08, 2020 9:23 am

RKB wrote:
Sat Aug 08, 2020 12:28 am
M52 converted e30

Not sure on the water pump will have to rummage through my receipts to see if its been changed.
M52s were fitted with a water pump with a plastic rotor, which tends to break up over time, causing cooling problems.
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flybynite
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Post Sat Aug 08, 2020 9:30 am

RKB wrote:
Fri Aug 07, 2020 8:26 pm
if I were to do it just lift the front and keep topping up the fluid with the bleed nipple open?
No that won't work on its own, get nose about a foot in the air...... it helps. Google bleeding e36 radiator. They can be a p[ig to bleed

Basically fill, -open bleed valve. - engine running and up to temp, - heater to hot, - squeezing pipes helps too

Be very careful running it until it is sorted as they don't like to be overheated as you can warp the head and pull head bolts.

I'd try to bleed it properly first but water pump is known weak point if it is one with a plastic impeller. Unless it has been replaced recently I would sling a new one on for what it costs.
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RKB
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Post Sun Aug 09, 2020 2:02 pm

By the looks of things water seems to be circulating fine, it's all bled up as did this quite a few times.

My fingers pointing at the new rad, and it being a bit rubbish.
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Brianmoooore
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Post Sun Aug 09, 2020 7:30 pm

Water still circulates with the odd pump vane missing. It just doesn't circulate well enough. Unless the pump is known to be good, preferably with a metal rotor it remains the chief suspect.
The cooling requirements of the M52 aren't significantly greater than the M20, if at all.