The V8 Owners Forum -

As the subject says but there doesn't seem to be a pipe leak. The manifold and gasket are new and I think I torqued the manifold bolts to 35 lbft.
Any other ideas?

Simeon wrote:As the subject says but there doesn't seem to be a pipe leak. The manifold and gasket are new and I think I torqued the manifold bolts to 35 lbft.
Any other ideas?

Might help if you stated which engine you're asking about.

And if the RV8, which exact version - there are loads of variations to the cooling system.

A leak from the thermostat housing or temp gauge sensor can allow water to collect in the valley. But it might be worth putting some dye in the coolant.

Hello Simeon, When you turn off a hot engine, the cooling system should maintain pressure for a few hours, until it is throroughly cold again.

If you are NOT losing pressure then it would seem unlikely that you have a coolant leak anywhere in the system.

Carefully releasing the pressure cap after (say) 30/60 minutes would be a reasonable test. Hissing and (perhaps) some steam will be your clues.

If you have no pressure, then a bottle of Bars Fluid might fix a small problem temporarily, sometimes permanently.

I'ts a standard 3.5 RV8 fitted in a westfield. I think the question i'm asking is could it be from anywhere under the manifold? If it's not then I think I can live with it temporarily until I can definitely tell where it's coming from.

I'm at the stage where I'm looking closely at the cooling system and have been unable to get the rad fan to work. I ran the engine last night for thirty minutes and it sat happliy at about 80C on the dash guage. I have fitted an adjustable Revotech rad fan controller and turned the adjusting screw all directions but the fan would'nt come on. I followed the wiring diagram to the letter when fitting it so am a little stumped and it does'nt help that I can't find the instructions anymore. Once again any ideas?

A quick google found this,
http://www.cobraclub.com/forum/dax-tech ... -help.html
Blue and red too live ? black to earth, is the thermostatic controller fitted in the top hose ?

Simeon wrote:I'ts a standard 3.5 RV8 fitted in a westfield. I think the question i'm asking is could it be from anywhere under the manifold? If it's not then I think I can live with it temporarily until I can definitely tell where it's coming from.

I'm at the stage where I'm looking closely at the cooling system and have been unable to get the rad fan to work. I ran the engine last night for thirty minutes and it sat happliy at about 80C on the dash guage. I have fitted an adjustable Revotech rad fan controller and turned the adjusting screw all directions but the fan would'nt come on. I followed the wiring diagram to the letter when fitting it so am a little stumped and it does'nt help that I can't find the instructions anymore. Once again any ideas?

There's no such thing as a standard 3.5 RV8. Pretty well every installation had variations to the water pump, hoses etc. And most have a mechanical fan. Each will have more likely places to leak from.

If it's an early injection engine as fitted to the Vitesse, there's a steel pipe which runs under the inlet manifold which rusts through and leaks. Carb cars use a different arrangement.

On my EFI, the thermostat is 88C, so I'd not expect any cooling fan to come on at 80C Earlier carbs cars were 82C. But again, I'd not expect a cooling fan to operate much below 90C.

Hello Simeon, I'm not familiar with your fan controller, it may even be badgered, but you may be able to check out the fan by applying 12 volts directly to it from the battery and see if it runs OK.

Ask the manufacturer first tho' in case its a modern motor with sophisticated motor contrl functions.

If it doesrun, then suspicion falls on the controller, the thermostat or the local wiring.

Regarding the Controller instructions you may be able to get them from the manuafacturer. I googled and found their site

http://www.revotecdirect.co.uk/acatalog ... llers.html

there are email addys and phone numbers too but I did not find any online fitting instructions as the link seems to be broken.

They should be able to email them to you tho'.

.

I've sussed the fan controller problem.

I had wired it in correctly however my 12 volt source came from the Westfield loom. What I did'nt realise was the loom had it's own relay so my 12 volts wasn't available until the first relay was energised. Fixed by removing the relay and bridging the connections.