23 replies to this topic

[medlow]

Hello people! I am due to change the original radiator very soon but would like a very quick question answered. After the new rad has been fitted and connected, I will obviously fill back with coolant. Are there any tips that I should know about regarding getting the air out the system?? I ask as the rad is a very long way from the expansion tank and engine so there must be a greater risk of air hiding somewhere..? Is it like any other system, or does extra special care need to be taken when bleeding the system.???? Also, what coolant would you suggest?? Please help. MED.

[Muncher]

When I changed mine I used standard Vauxhall coolant, the price is pretty good compared to standard Halfrods stuff.

[cyberman]

I had trouble getting all the air out of the system (some is dissolved in the fluid and some in the gas form trapped). Eventually I took the pressure cap off and let it idle till it boiled (well maybe not actually boiled but blew lots out of the inlet) and kept filling it up and then stopped and recapped. This worked wonders. I guess steam was replacing air as it got warm. I believe there is a bleed screw on the rad but I didn't notice it. I expect someone has a more sanitary procedure they will advise but this worked OK.

[medlow]

Thanks Cyberman! Any other views on getting air out the system?? I'm wanting to do this before a drive to southern Ireland in 3 weeks. Thanks all! MED.

[markv]

Maybe this one is of some help:

http://www.speedster....., Z20LET).pdf

Mark

[JG]

Maybe this one is of some help: http://www.speedster....., Z20LET).pdf Mark

I presume from this section:

10. Apply pressure to cooling system 1.0 bar to 1.5 bar
• Use commercially available tool with adaptor KM-471

That KM-471 fits to a std compressor?

[CocoPops]

Oooh I like that idea, pressurise the system to force the air out .

[CocoPops]

Hmmm, just googled the part number... 69euro.... not quite so good. Perhaps we can make one by modifying an old coolant cap.

[JG]

i guess thats how it works. got plenty of caps to modfy.

[techieboy]

Just how often are you planning on replacing the coolant? I've never had an issue refilling from empty before.

[JG]

for some reason, from complete empty to complete refill, i'm still not getting circulation. Not driven it on the road yet, that may help.

[techieboy]

Not driven it on the road yet, that may help.

That will definitely help. When I replaced the radiator hoses and rad before Le Mans last year, I totally drained the system. On refilling, I puckered up and got familiar with the expansion tank to make sure I got it done in one hit. Worked a treat and the coolant level hasn't budged at all since then. Using the Exige hose with the more accessible bleed valve made life much easier as well.

[JG]

i think having the water pump out has made quite a big difference, i used to have no problem changing the collant, which i used to do as soon as it lost its nice seethroughness.

[techieboy]

i used to do as soon as it lost its nice seethroughness.

Tart!

[techieboy]

Though I'm a fine one to speak. Must have had 6 total coolant changes in about 10k miles.

[JG]

I was about to say!

[Rally]

By coincidence, I refilled the system on my car today after replacing the rad. After filling it up and using the bleed valves, I started it up but after the engine got hot it was clear that the coolant wasn't going through the rad due to a massive air lock in the top hose. I ended up taking off the little hose from the expansion tank and used it to suck the air out. It did the job but I did then spent five minutes spitting out the taste of coolant.

[MartinS]

One tip I was given, was to raise up the rear of the car when bleeding?!

Martin s

[TazN]

One tip I was given, was to raise up the rear of the car when bleeding?!

Martin s

Seen it suggested in several threads to have the car parked up or down a slope with the end you are using the bleed nipples on to be higher up.

[Andrew aka Stuwy]

i cant remember how we did mine really, just opened all bleed niples and topped it up, took ages...