Is this normal?

[dixiebabes]

Noticed a water leak under the bonnet from the tope hos to the water pump, Knackered Jubilee clip, lost a bit of water taking the hose off to fit new clip, Refilled and ran stationary till i thought the air had been bled through ie thermostat opens and heater matrix pipes go warm. Replace cap and go for a run. Car usualy sits on about 60 degrees, went up to 90 and stayed there crept up to 100 then i arrived back home. Removed swan neck cap after releasing what seemed like an age steam and topped up with over 2 kettles full of water? Like i said is this normal? Cheers in advance lads and lasses.

Add to this will have been leaking for a week without noticing!!!


Dix

[honestjohntoo]

dixiebabes said:

till i thought the air had been bled through ie thermostat opens and heater matrix pipes go warm. Replace cap and go for a run. Car usualy sits on about 60 degrees, went up to 90 and stayed there crept up to 100 then i arrived back home. Removed swan neck cap after releasing what seemed like an age steam and topped up with over 2 kettles full of water? Like i said is this normal?

Unfortunately, just letting it warm up whilst stationary wont get rid of any air trapped in the system, it has to be burped out.

Read this to resolve the issue.

http://www.vintagemodelairplane.com/pages/TipsAndT...

In my view, 60 deg C for a V8 flapper is very low for an engine designed to run at or just above 90 deg. Are you sure the temperature gauge is working properly?

The instability you describe smacks of air locks but too low running temperature suggests gross over-cooling.

With that, the Efi engine will run far too rich, the extra fuel will wash oil from the bores, emissions will be high, performance below par, economy will be pants and wallet even more empty than normal.

If its a viscous cooled system the fan could be permanently locked up or the wrong thermostat is fitted.

If its got electrical fan cooling - it is wrongly adjusted. Read this for best cooling system performance.

http://www.vintagemodelairplane.com/pages/Rover_Te...

[dixiebabes]

Hi John it smells rich but it has just passed its test and it read emissions were very good?

Fuel economy aint that bad about 22 mpg to the gallon and its ran around 60 degrees since i had the car, creeps up when no air rushing through rad, but never usualy more than 85?

Your right about thae "Burping it out" seems to have settled itself and repairing the leak should obviously help. Was a bit worried about the steam in the system but that seems to been cured by running it for a while and bleeding itself through!.

Dix

[dixiebabes]

Also the electric fans only ever come on about 85 degrees and thats usualy when the car is stationary?

slightly baffled here?

Dix

Thanks for the quick reply by the way John.

[tallbloke]

Hmmm, my fans are wired on permanently and the temp gauge always settles around 90. I wonder if it is over reading. I had my rad rebuilt with 20% extra cooling area too. I wonder if my water pump is lazy. Think I'll test the water in the top hose with an electronic thermometer. Good info here, thanks guys.

[Solitude]

my fans are wired "on" permanently too.
Can anyone answer why this has been done/if its normal, or is it just a safety measure ???

Gavin

[honestjohntoo]

honestjohntoo said:

tallbloke said:

Hmmm, my fans are wired on permanently and the temp gauge always settles around 90. I wonder if it is over reading. I had my rad rebuilt with 20% extra cooling area too. I wonder if my water pump is lazy. Think I'll test the water in the top hose with an electronic thermometer. Good info here, thanks guys.

Just lets be clear, you cant have too much cooling effort available - when needed - so no worries there then?

But if the Efi engine is running too cold continuously, then its inefficient, induces unneccessary wear due to overrich mixture washing oil from the bores. the mpg will be lower than one expects or can afford, and the overall performance is way off spec.

One may however relish in the extra bangs a rich mixture gives and love the boost you get. Its a heavy price to pay tho'!

The reason your car is able to maintain approx 90 degrees C is because you almost certainly have an (correct) 88 deg thermostat which does not start to open until 88 degrees or thereabouts.

Thus even if one strapped a fridge around the radiator there would be nothing to cool until the thermostat opens and lets the hot water thro'.

But then you knew that already - right?

So what about a car that is running at 60 degrees C on journeys? Wow - to my mind thats a disaster waiting to happen and its already being expensive.

For comparison my 3.5 running the same system will turn in typically 28 mpg in a non urban journey of normal traffic, pulling a car which is a lot heavier than a TVR and it NEVER runs below 90 to 95 degrees C. the only difference is that its a twin plenum.

Thus the manifold temperature, where the sensors are located, tell the true story to the ECU and the temperature gauge. The ECU responds by fuelling the injectors exactly right for the engine at its optimum running temperature and the gauge remains rock steady if you are running a viscous cooling fan that uses negative feedback to judge just how much cooling to apply to the radiator.

If all the above is still leaving a person moggydawed, I urge another reading of the second article mentioned earlier - and review it several times - to get the cooling process clear in one's mind.

Look at it this way. When these engines left the factory they ran spot on the manufacturers specified running temperature and, by and large, were rock steady. Anything else and the car would have been sent back as "not fit for purpose" by the buying clientelle. Of course my experience is limited to the Efi RV8 installed in the SD1, not the toys mentioned hereabouts.

[tallbloke]

honestjohntoo said:

Info...

Thanks John, hopefully I have the correct thermostat in. I notice most of the v8 thermostats on the 'bay are for Landrover's and are set for 74C.

[grahamw48]

Solitude said:

my fans are wired "on" permanently too.
Can anyone answer why this has been done/if its normal, or is it just a safety measure ???

Gavin

Sounds a bit suspect to me, and must be overcooling half the time.

Try disconnecting and see if any issues (not when stationary) are revealed.

All my V8 Wedges' fans only came on when standing in traffic for a while, or after a particularly (ok...normal ) spirited drive out in warm weather.

Came on above an indicated 90C.