The V8 Owners Forum -

I have a new to me kenlowe 240v preheater

Where on a 3.9 v8 is best to fit it?

I would look at the heater circuit. I presume it's always 'open' on that vehicle.

Chris.

I’m not too sure to be honest

I can always take the thermostat out

I’m hoping that it warms the coolant enough to Demist it quicker

This says heater circuit!

https://www.academia.edu/5980242/Kenlow ... structions

Bit curious. You remove the thermostat making sure the heater doesn't work and want to heat the coolant by electricity?

Stuvy wrote: ↑

Mon Nov 09, 2020 7:54 pm

I’m hoping that it warms the coolant enough to Demist it quicker

I've never known a V8 take long to warm enough to demist the car! Are you sure your thermostat is working?

Chris.

Stuvy wrote: ↑

Mon Nov 09, 2020 7:54 pm

I’m not too sure to be honest

I can always take the thermostat out

I’m hoping that it warms the coolant enough to Demist it quicker

Don't take the thermostat out!
Make sure its working - not stuck open, and re-fit.

Will test the stat this weekend

It’s just to thaw the screen in the coming weeks/months

Iv been spoilt as my Rav4 heated up in no time and had the best heater Iv ever had in a car

I don't think removing the t'stat is a good idea at any time but if you did then your pre-heater/pump would presumably be heating the coolant then pumping it around the whole cooling system, including the radiator which would then radiate that heat you've just added so even less good.

I think the heater circuit has to be permanently open on the RV8 as this is how the flow takes place when the t'stat is closed IIRC which sounds like exactly what you need.

All the race cars I worked on didn’t have a thermostat

Where would be the best place on the heating system?

Stuvy wrote: ↑

Thu Nov 12, 2020 9:13 pm

All the race cars I worked on didn’t have a thermostat

Where would be the best place on the heating system?

Didn't realise this was a race car, so presumably no heater?
Depending on configuration should still have outlets in system for heater? Plumb it in there.

its not

It’s a disco v8 3.9 efi with a kenlowe day in its boot waitignto be fitted was just seeing if anyone had an real world experience of where to plumb one in

As surely the thermostat would restrict the flow of the hot water, if memory serves correct it heats to 45degrees

It was just to heat the coolant to clear the screen as I don’t have a place to park the car under cover

What not try a fan heater inside the car for a couple of minutes?
I have tried that, extension cable and run the fan heater for 3 to 5 minutes and the ice on the screen was completely melted!

Much more simple in my opinion!

Ian

Stuvy wrote: ↑

Sun Nov 15, 2020 2:45 pm

its not

It’s a disco v8 3.9 efi with a kenlowe day in its boot waitignto be fitted was just seeing if anyone had an real world experience of where to plumb one in

As surely the thermostat would restrict the flow of the hot water, if memory serves correct it heats to 45degrees

It was just to heat the coolant to clear the screen as I don’t have a place to park the car under cover

Oh, so I'm a bit confused why you brought the subject of race cars up then.

Anyway. When the thermostat is closed coolant must still circulate around an engine otherwise the static water would just boil in the head and that would end badly.
The T'stat only stops the coolant circulating around the radiator part of the sytem, which would be bad for your heater as it would be throwing away a significant amount of the energy supplied through the radiator. Even without airflow a radiator will still 'radiate'.

On the RV8 engine, at least all the ones I've seen, the heater system is permanently 'open' and this supplies a circuit for the coolant (unlike some other systems I've seen which have a valve in the heater system and must allow circulation via some other channel), this should give a convenient point for you to pipe in your pre-heater, as it would then only be circulating heated coolant around the engine, pre-heater and heater matrix.
OK, you will lose some heat via the heate matrix but this is also effectively a small radiator but this will find its way into the vehicle (if the vents are left open) so not exactly wasted.

Assuming the Kenlowe allows unrestricted flow when not in use it should be OK to plumb it into either of the pipes between engine and heater matrix, shouldn't really matter which.

My SD1 EFI has a vacuum operated valve which shuts off the flow to the heater matrix when the AC is in use. Perhaps they reckon you'll only use AC after the thermostat has opened?