Cooling advice

[Tango1360]

Hi another newbie question

Did a bit a work on the cooling system at the weekend consisting of the following
flush and back flush and flush again
new hoses and 82 deg thermostat ( correct for the engine number)
refilled with 50/50 antifreeze.

As far as I can tell its a standard Mk2 TV8 with viscous fan and original cooling setup.

My question is from a cold start how long does it normally take the engine to get to normal operating temp at idle

I left the car running to check for leaks -all ok but, it took only a couple of minutes for the temp gauge to sit at half way.
An infrared thermometer measured 75 deg at the top and 65 deg at the bottom( although its not a calibrated instrument)

Is this normal or have I missed something
My other car (herald 1360 ) take a lot longer to warm when idling.

Cheers

[Mark Shutt]

mine takes aabout 10 mins to warm up when idling but only about 5 mins when actually driving..

[uzbek]

Mine takes bit longer maybe 15mins at idle before the temp stabilises and the stat opens-but mine is an 88 degree one.

Driving about 5-10mins max.

Yours sounds as if might be rising a bit quick-airlock maybe. However don't trust the gauge value automatically-unless the IR reading taken beside the sender is the same. Best to go off that.

When warmed up my gauge is almost spot on to the block temp give or take a few degrees, but lots are not

[Lingen]

Something not right there Tango. Perhaps your new thermostat is one of the dodgy ones going about that doesn't have an air bleed (see recent thread). If it hasn't, send it back to the supplier with a rude letter! It would normally take around 15 mins. for a cold engine to get to working temperature at tickover speed. Exactly what was 75 at the top, and 65 at the bottom? I reckon there is no coolant circulating at all. Also, I.M.H.O. 50% antifreeze is a bit much. The higher the percentage of it, the less the ability of the coolant to absorb the heat of the engine. 33% should be enough to protect everything, without the possibility of things getting a bit hot when and if we get a decent summer.
Mike.

[Knockwurst]

Mine takes about 15 minutes at idle too before the leccy fan starts to regulate the temperature. IR temp measured at sender, thermostat housing and rad top are all around 85'C.

[LAMBRETTLAD]

I use 50% anti freeze and zero problems , and as with all stag related topics "as yet "

[V Mad]

I would rather have a bigger cooling margin, so I stick to 25% to 30% max.

[Staggard]

I use 50/50 Bluecol I don't have a cooling problem so prefer a bigger corrosion margin

[Tango1360]

Thanks all for the advice, when I bought the car it didn't have a thermostat in, so I wasn't sure what was the normal warm up time.
I thought air lock, has anyone thought about a bleed valve on one of the heater hoses, I know some modern cars have them.
I'll check the thermostat in a pan of water at the weekend and post back more temp readings, once I confirm if its the thermostat
cheers

Brian

[Lingen]

Brian. Even if the thermostat was faulty and not opening, the engine wouldn't get hot anything like that quickly. The important thing to check is that there is a hole in the rim of the thermostat to allow any air in the engine's waterways to vent into the top hose when the thermostat is shut. Without one, the block and heads will be starved of coolant. There is no need to have bleed valves anywhere. With the correct thermostat, the engine will quickly self-bleed as you fill the radiator. That done, you just need to run the engine with the heater valve on "Hot" to quickly bleed the heater as well.
Mike.

[Johnh]

Hi Brian,
I have recently been suffering problems with my gauge following a removal and overhaul of the heater. I have so far replaced the Thermostat 82deg but I had to drill a small hole as it came without one. I got this bit of advice from another thread.
I also had a lot of air in the system and was advised to get the nose up as high as possible ramps, axel stand etc. and then keep topping it up, an occasional few turns of the engine seemed to help.
New sender fitted and it has slowed the rate of the gauge rising but I think a new solid state voltage stabiliser will be installed and a thorough check of the connections and earthing.

Good luck.

JohnH.

[uzbek]

The fact the previous owner removed the thermostat on your car makes me a bit anxious about how well the cooling was working previously.

Van you find out from them?

[Ian F]

Check which Inlet manifold you have, even though you have checked the engine number. I understand some Inlet manifolds ( "Mk2") have the by pass below the thermostat and need the thermostat with the foot to block this off.
Earlier versions don't have the thermostat foot or by pass and fitting the later thermostat to mine ( must have early manifold) caused it to run too hot. Soon resolved when I put the original back. Just a thought?

ian F

[andy p]

I run mine on 50/50 anti freeze and it prob take 10 min for the needle to move off the cold mark

[elvimto]

You can fit a bleed into the return line,top radiator hose buy it from one of the companies in the UK that make them I made my own it fits right before the hose goes into the raad and I have a digital sensor in it and a spare tap for a sensor fro the electric fan when I fit it. This is what I mean.
valve.jpg