Hi,

I want to swap my old tiger rad for the obligatory Polo version and intend to get rid of the heater too. I have attached a pic of how my cooling system looks now(no thermostat by the way)


4age now

The question is, can I just remove the heater and loop the hot(?)side from the pump to the (cool?) side at the back of the block as such?


4age without heater

Any other comments would be welcome.

Thanks, Mark

Can,t see a prob with that as heater is only long pipe with a valve on

id imagine you could just block off both ends. ive got the same and plan to remove heater over winter

This is how mine looks like (without the bleed) and got a drawing by raw of this.

[img][/img]

quote:

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Originally posted by shades
id imagine you could just block off both ends. ive got the same and plan to remove heater over winter

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Thanks guys, I think that I will give this a go..


4age without heater rev1

Any one got a polo rad going spare?

Guys,

I have eventually finished the cooling mods and have installed as per the picture below;

4age without heater rev1
The problem is my temp guage is going upto 110degrees before the fan cuts in.
The thermo switch is a brand new one that should cut in at 88degrees.

It seems that the temp of the water in the rad is not as hot as it is at the head(sender unit)

What have I done wrong with the plumbing?

Cheers,

Mark

where are you measuring the watertemp?
sure your sender is correct, eg dropping the sender in boiling water should read 100°

looks like the same plumbing as mine exceprt for the blled, I've got no bllep pipe going from the rad to the header tank.

Do you have a thermostat in the system? if so check if it opens, again with boiling water.

Is the waterpump working, eg moving water, heard of a few 4age waterpumps where the impeller slips over the axle when hot and thus not spinning anymore.

The water temp sender is in its original position on the head. I am sure that every thing is working because it was before I altered the plumbing.
There is no thermostat fitted and never has been.
I am concerned that the flow is wrong at the T piece I have installed at the back of the motor. The water is flowing out of the back of the head and I am forcing it back to the header? I am sure that the bottom pipe from the header should loop back to the bottom hose near the rad.
Like this;

plumbing mods

I am going to give Mel at RAW a ring today.

this may help a little and ill try and post a pic of my coolant system... Its been good for over 65miles. (the drive to an SVA i was late for)
Rescued attachment 4agwater.gif

Heres an image of my coolant cycle. As you can see the thermostat is not housed in the waterpump housing but in a separate housing. This is the way it came with the MR2. The RWD engine ive got from a corolla is housed in the water pump housing.

This shows the two circuits; one bypasses the thermostat but provides the switching temperature for it and the other passes through the thermostat and the radiator. The pressure cap ive used has an expasion tank bleed off which feeds into the expansion tank. The expansion tank feed is below the water line and there is an air escape hole in the top so its a non pressurised system. This means ive done away with a header tank which is what i think youve been calling an expansion tank in your pictures (correct me if im wrong)

As i say this has been good for 65 miles and seems to work just great. Ive not measured the temperature of the engine directly but the gauge doesnt enter the red even when its stood around for a while (the fan kicks in)

Hope this helps you to design your own system...

Cheers
Fin
Rescued attachment coolant_cycle.JPG