I've finally got around to fitting my alloy rad and electric fan set up.The problem is do i have to fit an expansion tank to the rad or can i just bin the old leaking one and run it without. :confused:

id also know do you need it.

 

im putting my standard rad back on the car, cant remember if i have the pipe that connects or what the rad/expansion tank connects to :rolleyes:

No i belive you cant loose the expansion tank .

whats the purpose of it then?

 

just stores a little bit of water to feed the radiater if it runs low isit?

Does what it says really.

Water expands when it heats up and runs out to the expansion tank then as the engine cools it's drawn back in.

Without it you'd have to top up the radiator more often.

If you get a leak there's a lot less water in the system without one so a bit more risky.

Technically its an overflow tank rather than an expansion tank.

 

As Chris says, as the water expands from heat and the excess water is pushed into the overflow tank, and then when it cools the vacumn sucks the water back up. Without the tank the rad will push the water out onto the floor and then you run the risk of it running low.

 

Thats the theory anyway, in reality I've heard of some removing it without apparently ever having issues,

Edited May 15, 200916 yr by Yowser

My mate cooked his s13 running with no expansion tank so not a good idea.

ok.

 

so does the expansion tank need to be full of water aswell then or empty? or half?

ok.

 

so does the expansion tank need to be full of water aswell then or empty? or half?

 

It's got a dipstick on it with the level hasn't it?

Haven't looked at mine in ages cos I check the rad level before every trip.

If you have a standard radiator, then I would keep the expansion tank. If you have an aftermarket radiator, which has a larger core, then no, bin the expansion tank as you will hold more water in the A/M radiator.

 

Al.