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Bob
20-10-01, 08:03 PM
My Sumo runs hot on the gauge 100 degrees+ but the engine doesn't feel that hot nor are any of the water pipes that hot and the fans dont come on until the guage gets to 120 and then the temperature drops to 100 or just over. I havn't taken it on a run yet SVA still pending. Her's the question could it be because the seder unit in the Edlebrock manifold is right next to the exhaust port so that area gets hot and gives a high reading compared to the rest of the engine. I've fitted bleed valves and summer thermostat. any ideas will be gratefully recieved. thanks.

kev
20-10-01, 11:14 PM
I assume youv'e got a standard thermostat in that opens somewhere around 82 and as you've said you're confident that the water coolant system is working ok. Bear in mind that your temp. gauge isn't calibrated to the temp sender so at best it's only a guide, therefore the best way to check your gauge is to set the cooling fan thermostat too high and go out for a run. Then you can see what the temp gauge reads as a result of the engine temp set by the coolant thermostat under normal conditions. That temp is then your norm and you can set the fan to come on just above that reading. Don't place much emphasis on the reading on the gauge unless you pay big bucks to have it calibrated and run it under a regulated voltage condition. Also because the cooling system is pressurised the coolant can run above 100 C before boiling, but here's a thought, is your temp gauge calibrated in centigrate or fahrenheit?

Good luck with the SVA
Kev

Bob
21-10-01, 09:04 AM
Thanks Kev. Going for the run is the hard bit when the car not legal yet. I assume its in Centigrade.120 being the top reading.My fan switch is in the radiator not a separate Kenlow switch, Pilgrim say that they should come on when that part of the radiator which is down by the bottom hose gets to 88. How did your top hose turn out.

wilf
21-10-01, 11:21 AM
Bob - as Kev says, temp guages are notoriously unaccurate. As a quick check, if you can run the engine in the garage for 1/2 hour on slightly elevated tickover rpm, (say 1000 - 1500 rpm) with the cooling fans coming in and out and no signs of steam/water from the overflow nor any other distress from the engine, I would think you are OK. This would be a more severe test than going for a run, since there would be no natural airflow thro the rad/over the engine. Think of sitting in a traffic jam, crawling forward a car's length every few minutes!

After a while, you will get used to what is "normal" for your guages.

HTH

Wilf

kev
21-10-01, 07:18 PM
Top Hose?
I think there are too many Kev's on this forum , Im the one with the AK, Kevin Tams ;-)

Kevin W
22-10-01, 10:56 AM
Hi,
I'm the Kev with the top hose problem!
Its nearly sorted now - rather more jigging about than I'd thought, but its nearly there now.

Kev (Wells)

STEVE G
22-10-01, 11:10 AM
Bob I found with an electric temp gauge I got frightening temps. but since changing to a mechanical Smiths gauge it reads a lot better.It seems all rovers tend to run a bit hot but as long as you have no airlock in the heater you should be OK. Mine runs about 80 degrees max but will get up to 120 at a standstill and drop down again as soon as I'm moving again.By the way I also have a mechanical oil temp and that rarely gets above 60 degrees which I beleive is probably a better indicator of engine temp.

Bob
22-10-01, 01:20 PM
Sorry about that but thanks for the reply.

Bob
22-10-01, 01:21 PM
Thanks Wilf I'll give it a go.

Bob
22-10-01, 01:26 PM
Thanks,I've got an electronic oil temperature gauge it starts at 50 and so far I've not seen it move.I wouldn't know how to start testing if it works ornot but it should do its brand new from ETB.

StuartH
22-10-01, 01:45 PM
Probably better to do it outside the garage though!! :-)

Bob
22-10-01, 04:39 PM
Why dont you like that nice whoosey feeling you get from carbon monoxide.I tried what Wilf suggested today.I set the tick over to 1500 and let it run the temperature climed to 120 in about ten minutes and the the fan came on and the temperature dropped to just under 100 after another ten minutes it had climed to 105 and just sat there this time the oil temperature gauge rose to 60 and the oil pressure dropped to 15 PSI which is about right for a Rover.There did'nt seem to be any problems no gurgling noises ore hissing of steam and no nasty knocks from the engine inners.I would still feel happier if it ran at about 90 . I think I will take the thermostat out and see what happens without it. Thanks again for the help lads.

wilf
22-10-01, 06:27 PM
Bob - that sounds like a good result, and much what I have observed in my own car. I might have expected a bit more than 15 psi at 1500 rpm hot tho' - again the gauge could be out. I would not recommend running the engine for long with the 'stat out - engines will wear out pdq if they are run at much below "normal" temps, but at least it will give you a comparison. To finally lay the thing to rest, I would suggest you find a good, accurate electronic thermometer and check out the actual temps in the water system. As we have all said, you plain cannot trust car instruments to give accurate readings. I know my guages under-read by at least 10 degrees C - and they are expensive Smiths mechanical gauges.

One thing you could try to calibrate your guage is this - take the water temp sensor out of it's housing, but leave it all connected, and drop it into a boiling kettle of water (if you can wangle a kettle into the space you have). Boiling water is as good at 100 degrees as makes no difference. See what your gauge reads - bet it is well over 100 degrees on the dash!!

Wilf

PS Kettle wangling is an old Leicestershire pastime, much like breathing carbon monoxide must be up your way!