RV8 Cooling

[tonym]

Originally Posted by ti

Is it possible that you have fitted the stat the wrong way round ?

Not sure it will fit in the wrong way round but worth a look

[philip600]

Hi Terry,
It won't go in the wrong way round ( I don't think ) but if it did would that not cause it to overheat ? ie not open because it's on cold side of housing ?
Regards Phil.

[big_guy_unlimited]

Does anyone have any more theories on this one?
As i too suffer with the engine staying at 60ish degrees when running?? Mine is a Rover 4.6.

Mine too climbs steadily to 80ish degrees at standstill but soon drops off when moving. If i've been out for a run, it sits around the 60mark when running, when i get back it gets hot enough for the fans to kick in, if i leave it running while i open the garage door.

I agree with DELAGE theory, is the radiator area to large/good? I’ve got an SD1 refurbed radiator. If i blank off - say half - would the temperature then raise?? I'd have tried it at the weekend but the loverly weather dampened that idea!! Also if there was a small hole say 5-6mm past the thermostat (I'm thinking of a smaller diameter hose connected from the thermostat housing to the top of the radiator) would that allow enough water flow past the thermostat to allow the engine to keep cool at the 60degree mark?

Something I’ve just thought of, I’ve got a separate oil cooler fitted in front/below the main radiator, would this be enough to drop the overall engine temp?

Very intriguing indeed!?!?
Thanks

[Sidecarbod]

I can't see that having too big a rad would be an issue, the rad size should not be the thing that determines the temperature that the engine runs at. That is the job of the stat. The rad should always be too big in that respect so that it can cope with the two hot days that we call "summer".

My 4.6 has a 74 degree stat with three holes drilled in it yet it still controls the temperature within a fairly narrow range. Once up to running temperature the engine temp should never goes below the stat closing temp, if it started to drop the stat would close until the water in the block was hot enough to open it again. I also run an oil cooler which at the moment is not evening running a thermostatic plate! You'd have to cool the oil a hell of a lot before it could pull down the coolant temperature, in fact I doubt that it is possible to get the oil that cold!


I don't think that the small bypass tube could flow enough coolant to get the temp down to 60 degrees.

Please don't think that I'm spouting off as the "all knowing one" as this one has got me as stumped as the next man!

Pete

[wilf]

Of course, the very first things I would suspect would be the temp gauges.......about as much use as a chocolate teapot when it comes to finding out what temps are REALLY happening.

Get a decent electronic thermocouple type thermometer to check things first.

[DELAGE]

Mmmmm, well glad some one has read my post, I am not an expert on RV8's but have built around 15 of all sizes in various stages of tune. So my suggestion re the rad does make some sense to any body with the meanness of intelligence. If the car with still air working with the kenlow on the drive way and blanking off the rad in some area's on the road the engine reaches the desired temp it must have some thing to do with the cooling capacity of the radiator when in full flow on the road. Is it 3-4-5 core rad?

Gauges I will agree will vary but not a drop of 80 to 60 deg's. I have already explained that the modern wax-stat does not always do what it says on the tin, unlike the old type belows jobies.

My 4:6 I built from scratch with no help, not half an engine I purchased from some-one and added my 3:5 bits too. But I would say in all fairness my silicone hoses with no joiners contributed to my drop in temp but I do have a RV8 front cover with a rather large water pump and oil pump as fitted to MOD ambulances.

[Sidecarbod]

Originally Posted by DELAGE

Mmmmm, well glad some one has read my post, I am not an expert on RV8's but have built around 15 of all sizes in various stages of tune. So my suggestion re the rad does make some sense to any body with the meanness of intelligence. If the car with still air working with the kenlow on the drive way and blanking off the rad in some area's on the road the engine reaches the desired temp it must have some thing to do with the cooling capacity of the radiator when in full flow on the road. Is it 3-4-5 core rad?

Gauges I will agree will vary but not a drop of 80 to 60 deg's. I have already explained that the modern wax-stat does not always do what it says on the tin, unlike the old type belows jobies.

My 4:6 I built from scratch with no help, not half an engine I purchased from some-one and added my 3:5 bits too. But I would say in all fairness my silicone hoses with no joiners contributed to my drop in temp but I do have a RV8 front cover with a rather large water pump and oil pump as fitted to MOD ambulances.

Oh well,

Still sounds like bollox to me.

Did it take 15 engine builds before you got one right?

Pete

[craggle]

Just to jump in here, I agree with Pete.

The thermostat controls the temperature and not the rad size. Some marine engines have a radiator the size of the Atlantic ocean but they still run at the correct temperature. The thermostat just allows enough hot water out the engine to keep it at the right temperature.

It is very easy for the Rover stat to slip out it's housing when you are fitting the thermostat cover on the top. If it gets trapped under the gasket it may not leak but will distort it enough to make it stick either open or closed.

Just another thing to consider, On the Range Rover P38 4.6 and 4.0 versions they moved the thermostat from the inlet manifold to the lower hose. This means it is now opened by radiator temperature and not engine temperature.
Any idea why?

Craig.

[TINKA]

Agree with Pete and Craig, the size of the rad is not the cause here, now if it was always over heating because it could not cope then that is a different matter. A friend of mine has either a 5 or 6 core rad on his cob and has never had problems with it running too cool.

[Sidecarbod]

Originally Posted by craggle

Just to jump in here, I agree with Pete.

The thermostat controls the temperature and not the rad size. Some marine engines have a radiator the size of the Atlantic ocean but they still run at the correct temperature. The thermostat just allows enough hot water out the engine to keep it at the right temperature.

It is very easy for the Rover stat to slip out it's housing when you are fitting the thermostat cover on the top. If it gets trapped under the gasket it may not leak but will distort it enough to make it stick either open or closed.

Just another thing to consider, On the Range Rover P38 4.6 and 4.0 versions they moved the thermostat from the inlet manifold to the lower hose. This means it is now opened by radiator temperature and not engine temperature.
Any idea why?


Craig.

Cheers Craig but look out, you'll end up in the firing line!

Pete