bleeding radiator

[jesfirth]

I need to bleed the radiator/cooling system on my 97 4.2 cerbie and would like to avoid the dreaded air locks etc.

Do I do it with the engine running cold, hot etc?

Thanks in anticipation

Jes

[Eddie 4.2]

Hi Mate


Look at the front sides of the engine the metal water pipes
u will see a tap lossen off both sides and let the air out
Do it with the engine running

Ed

[andy4200]

The way I did it was.

Fill expansion tank, then open the bleed screw on the corner of the rad until you see water coming out. Close bleed screw, top up exansion tank and put lid back on.
Run the car through a heat cycle (till the fans come on is probably ok). Let it cool down again. Repeat entire process 3 or 4 times. Et voila, no air.

I wouldn't use the two taps on the rails as they have a tendency to not seal properly when you close them again. The system is supposed to be self bleeding to an extent.

Whatever you do, do NOT open up the expansion tank or bleed screw when the water is hot. You will probably regret it after you burn yourself on hot water.

[Julian64]

Nope its not self bleeding. Or at least the manual tells you to use those taps. A careful look at the system shows you that the taps sit at the highest point on the water system so are still probably the best way to bleed.

[trackcar]

Yes it is self bleeding

the taps are a no-no as Andy says .. often don't seal if not been used for a long time so best not to touch them.

the metal cooling pipes have bleed pipes from the back of them direct to the expansion tank, they actively self bleed as the waterpump induced water flow is out of the pipes towards the expansion tank.

Pointing the car very slightly nose down also helps.
Adding water wetter (reduces the water's surface tension and chases out air pockets ) also helps.

[andy4200]

Anyone for Christmas panto

[Julian64]

Oh no it doesn't. la le lah lah lah.

So why does the factory manual tell you to do it?



And why when I built my kit cars do I always need to put the expansion tank above the engine?

Oh yes it does.....


Oh no it doesn't.....


Oh yes it does....

[trackcar]

Julian64 said:

Oh no it doesn't. la le lah lah lah. So why does the factory manual tell you to do it?

lmao, because (unsurprisingly) TVR got it wrong

[Rob Dance]

Well timed thread, I was going to search for "bleeding" advice today, as I am replacing the water pipes this weekend !!

Presumably it helps to have the heater set to "Hot" during this process, to encourage any air out of the matrix.

I will attempt to leave the taps well alone.

[jesfirth]

thanks guys much confusion but very amusing maybe I will try bleeding one side only