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Stratos
January 5th, 2003, 06:22 AM
Originally posted by Matt No VAT
Thanks for the advice guys :~)

I have the complete oil cooler setup from a 24v but will only fit that if I ever get to the bottom of why my car persists in its constant overheating problem. I thought I had resolved it yesterday when I replaced a few bits and changed the pipework to match John R's - but alas she's still acting like a giant red kettle.

Oh well back to the drawing board.

This is no longer funny:confused:

Originally posted by roger001
How old is your radiator core?

The standard rad is borderline on cooling, it does not take much in the way of corrosion/fouling etc to bring about the kettle immitation.

Originally posted by Stratos
Matt,

I'll echo what Roger said. The radiator must be in tip-top condition.

Richard Gibbons had a similar problem to you. He fitted my spare new radiator (which I loaned to him), and re-bled the system with the engine running on fast tickover, and that cured his problem completely.

Another point to note, the 24v engine needs a lot more cooling than the 12v - I can vouch for that from Alfa 164 road car experience.

Originally posted by Matt No VAT
I now have another question which I'm hoping someone can confirm for me:

On the Alfa V6 water pump housing there are the two large diameter connectors an upper and a lower, which is the FLOW TO the radiator and which is the RETURN FROM the radiator.

I'm getting somewhat suspicious that these have been connected up the wrong way.


Also I am far from happy with what I have discovered has been done getting the 90 degree bend into the two water pipes - Has anyone used 22mm Copper piping to do this?

I think it would be a far neater job than 32mm tube and huge 90 degree silicon bends - this way I can solder proper 90 deg. bends without fouling against the exhaust manifold. And reduce the number of jubilee clips used on my car! Just wondering about the volume of water it can handle.

Cheers


Matt,

I've asked that question before, and no-one has ever given me an answer.

I have never bothered about this, as to my way of thinking, it shouldn't really matter. I don't believe there is anything in either connection on the radiator which would restrict flow, so, regardless of which way round the pipes are connected, water will flow TO the radiator, THROUGH it, and then OUT of the radiator.

When Richard was having his problems, I know he tried swapping over the pipes, but it didn't make any difference. He tried almost every combination, including with and without a heater system.

Someone who knows something about radiator design might be able to tell you that it is more efficient for the water from the engine to go in at the bottom of the radiator, or at the top of the radiator, or that it doesn't matter.

David May
January 5th, 2003, 08:06 AM
I'm sure we've all had some sort of overheating along the road but I think it would help to break the topic down into one of 3 different problems:
1) Insufficient water flow - usually associated with air locks, header tanks and system bleeding trouble. Shows up at low power outputs, often at tickover.
2) Inefficient radiator - lack of airflow (fans, grilles), undersized or scaled radiator. Shows up when driving very hard at low speeds in hot weather.
3) Engine oveheating - insufficient oil and or water cooling. Likely to show up only in severe racing conditions.

They are all different problems which require selective measures.

Dave May

chris.richard
January 5th, 2003, 02:32 PM
pre-93 config 12v

chris.richard
January 5th, 2003, 02:33 PM
and again

chris.richard
January 5th, 2003, 02:56 PM
93-95 spec.

kens
January 7th, 2003, 09:17 PM
As we all know, a stuck thermostat can lead to problems. With what probably started out as an air pocket in a newly assembled engine, I had an overheating issue. Thinking that removal of the thermostat from the thermostat housing would prove or disprove the part, it was removed. Wrong!

Don't remove the thermostat, its existance is required for proper water flow. Proper cooling was restored with replacement of the thermostat.