keeping 4.3 engine cool

[Count Vampirski]

always had car running at upper limit, on edge of entering red when slow moving in summer.

Only has original single large one step Spal (working fine) - bought an additional one and stored away somewhere yrs ago..

I would prefer to add additional water volume and natural cooling (regulated by stat) than have annoying fan cutting in most of the time - has anyone added an additional small radiator in series (from a compact car or competition catalogue) and simply added it next to the fan - seems a far more appealing solution than whirring fans (and effect on engine idling as compensation kicks in) - alternatively are inexpensive more efficient rad replacements now available? - mine is in mint condition and a shame to have to expensively replace

would love engine to run at 90 not nr 100 deg ! - Having to run with heater on in summer traffic is no fun!

[chris212]

Are you sure the temp gauge is correct? I had to plumb in a resistor into the sender wiring to get a correct gauge reading. I used an infra red temp gauge and took readings around the thermostat when it was up to temp, letting the fans kick in and out. Check / replace the sender unit first .

[Hoover.]

I believe there are two different thermostats that are fitted to the rover engines....... might be worth getting the one that opens at a lower temperature......

I to have a 4.3 running on the single fan (changed mine a few years back as the bearings went and made a horrible screetching noise each time the fans cut in).... never had an issue with temperature, apart from the otter switch failed and fans didn't kick in, but the manual override soon sorted that (dash light button changed to manual fan override button)

[Count Vampirski]

thanks guys - does changing stat involve any bleeding in that position, if so how?

how can i find out what the 2 values are for sure and where to get the right one?

my fan bearing screeches sometimes when starting up - presumably a little rust from lack of use

The infra gun is presumably a pro tool? or can one be bought inexpensively?

[blitzracing]

There are also two different sizes of the size of the stat' holes, and TVR fitted the larger 30 mm one. If its been changed to a Range Rover one at any point its will have a smaller hole and lower flow through the stat'.

[WinstonWolf]

Fit a splitter and a smaller front plate. Mine struggles to open the stat when it's cool and I'm driving. The temp will rise in traffic but the splitter/small plate allows the airflow to bring the temp back down as soon as you get going again.

[FlipFlopGriff]

WinstonWolf said:

Fit a splitter and a smaller front plate. Mine struggles to open the stat when it's cool and I'm driving. The temp will rise in traffic but the splitter/small plate allows the airflow to bring the temp back down as soon as you get going again.

Smaller plate won't help a pre cat.
FFG

[Colin RedGriff]

Count Vampirski said:

The infra gun is presumably a pro tool? or can one be bought inexpensively?

No Infra red thermometers are cheap


http://www.maplin.co.uk/p/pocket-infrared-thermome...

[FlipFlopGriff]

or one of these:
http://www.amazon.co.uk/GM550-Non-Contact-IR-Infra...
I bought one and its great fun.
FFG

[QBee]

Colin RedGriff said:

Count Vampirski said:

The infra gun is presumably a pro tool? or can one be bought inexpensively?

No Infra red thermometers are cheap


http://www.maplin.co.uk/p/pocket-infrared-thermome...

There are loads of laser gun shaped ones on Ebay for about a tenner, but remember to buy one that goes over 450 degrees C, as you will need over 400 degrees if you are using it to diagnose an electrical misfire by testing exhaust manifold temps

[Barreti]

FlipFlopGriff said:

or one of these:
http://www.amazon.co.uk/GM550-Non-Contact-IR-Infra...
I bought one and its great fun.
FFG

Had to get one of these because you said they are great fun.
Now I just need the list of daft things you do with it ...

[Count Vampirski]

wow, who would have thought - shall have to get one of those!

Thinkin about it, the thermo wont affect the top end temp unless stuck partially closed - I imagine everything is original as i have owned car since 3k miles - with stat position, will i need to bleed, if so how?
i propose removing stat entirely and then using new gun to record temp compared to dash gauge

under bonnet temps do seem insane though - and she did boil once years ago

really would like her to run around 90 without need of fan in all but worst summer traffic jams

[FlipFlopGriff]

Is the rad original? If so you may need a recore to increase the flow which should help. David Beer used to do a 2 stage fan kit where the fans come on at half speed (which you set via a dial) and then another dial to set when they kick in at full speed. This would also help keep the temps down.

Ian - they are good. Used mine to see how hot the inside of the back door was at the weekend. Its in a sun trap and was 37.8 degrees C. Also tried it on the wood burner - frightening! Not actually used it on the car yet.
FFG

[QBee]

Barreti said:

FlipFlopGriff said:

or one of these:
http://www.amazon.co.uk/GM550-Non-Contact-IR-Infra...
I bought one and its great fun.
FFG

Had to get one of these because you said they are great fun.
Now I just need the list of daft things you do with it ...

Not daft:
1. Checking your tyre temperatures when you come back into the pits on a track day. If your camber is correctly set for maximum grip, then your tyre temp should be even across the width of all four tyres. If it is, say, warmer on the outside than the inside, then you have too little negative camber and your tyre edges will wear out too quickly. and you won't corner as fast either.

2. Testing for a misfire caused by lack of spark. Engine running and warmed up, check all eight exhaust manifolds, about an inch from the cylinder head. The fault will be the one (or more!) that are 100 degrees or more cooler. You can do this test with a cable tie, but it looks more scientific done with your new toy.

Daft:
The thermometer puts a red light spot wherever you point it. My (17 year old) kitten thinks chasing the spot of light around the hall floor is a great game.

[mk1fan]

When was the last time the system was drained, flushed and new coolant added?

I'd try that and fit the lower temp thermostat first.

[blitzracing]

The "water wetter " products work quite well, they effectively make the water a better heat conductor where it meets the metal components, so more heat gets pulled out of the engine into the cooling system. Plenty on Ebay.

[davep]

blitzracing said:

The "water wetter " products work quite well, they effectively make the water a better heat conductor where it meets the metal components, so more heat gets pulled out of the engine into the cooling system. Plenty on Ebay.

Works well on my pre-cat, used together with twin fans and a manual override switch I've never had over-heating problems.

I've found with non-contact IR thermometers there's usually a disclaimer in the small print that precludes their use for accuracy reasons if used on reflective surfaces, hence I'd use a contact probe version in the engine bay if reasonably accurate readings are required.

[PeteGriff]

Hi CV, my 4.3 Precat ran hot when I first bought it, fans came on a lot. I went through a process of having rad recored (was seeping slightly and silted up), new hoses and changing a faulty otter switch (fan control switch in swirl tank). This made such a difference and I was more confident in heavy traffic to the point she could be left running at idle and the fans would cut in and out nicely no overheating. After I designed and fitted my air splitter the cooling whilst moving improved considerably. I now have no worries at all and confidently use the Griff in all temperatures. I must add though that my 4.3 came with twin fans. If you are interested in running twin fans I did draw up the design for the twin fan mounting plates that bolt into M6 bushes within the radiator, I could make a pair up for you? All the best, Pete

[Chuffmeister]

I had only one fan working on my Chim without realing a couple of years ago. It coped in hot weather, but the fan stayed on a lot. I wouldn't go for the lower temp large bore stat as it is designed for hot countries and for the most part, the UK just isn't hot enough. You may find that the car doesn't get sufficiently warm in the milder weather.

I would definitely go down the route of an extra fan and fit an lower temp otter switch so that the fans cut in and out earlier. It is also worth adding a fan switch to the steering column with an LED, so you can switch the fans on manually and see when they're on. In hot weather, I turn my fans on manually the moment I get into heavey traffic.

It goes without saying that you need to ensure you have fresh coolant and no leaks in the system. Avoid the resistor/ sender mod, as this will only provide an accurate reading at one set temperator and the others will be wildly out. It would be worth purchasing a lead from the classifieds and downloading a copy of Roverguage so you can read the temperature the ECU is seeing.

[PershoreTVR]

Good evening chaps. I have a Griff 400. I was told that a stainless steel rad reduced the overheating issue? Might that be a solution as I've been saving up my coppers.
My 400 fan comes on in slow traffic so cooling is always a concern. To what degree should I be looking at rads in parallel (or was that in series? - must ask my old `o` lovely physics teacher) or the `wetter` water?