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The mkiv Supra Owners Club

Do i NEED a rad expansion tank?


SMiFFAD

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Ive fitted an FMIC, which meant the tanks had to be removed, at the moment i just have a pipe running into the bumper.

 

As i see it, all the tank does is catch overflow from the rad should it throw some out? As the cap will only allow water to pass once a certain pressure is achieved (about a bar) there's no way water can go back INTO the rad? Surly?

 

Maybe ive missed something, hence asking the question, but id be interested to hear opinions!

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Ive fitted an FMIC, which meant the tanks had to be removed, at the moment i just have a pipe running into the bumper.

 

As i see it, all the tank does is catch overflow from the rad should it throw some out? As the cap will only allow water to pass once a certain pressure is achieved (about a bar) there's no way water can go back INTO the rad? Surly?

 

Maybe ive missed something, hence asking the question, but id be interested to hear opinions!

 

Basically, yes. Your cooling system will vent excess pressure nearly every time you leave the engine to cool, especially if you've been driving it hard.

 

Once the engine has cooled there will be a vacuum in the cooling system that will draw coolant back into the radiator. The rad cap is designed to allow this. This is also the reason the overflow bottle has a tube that runs all the way to the bottom: you don't want to suck air into the system.

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Basically, yes. Your cooling system will vent excess pressure nearly every time you leave the engine to cool, especially if you've been driving it hard.

 

Once the engine has cooled there will be a vacuum in the cooling system that will draw coolant back into the radiator. The rad cap is designed to allow this. This is also the reason the overflow bottle has a tube that runs all the way to the bottom: you don't want to suck air into the system.

 

Yes i saw it had the set up to draw water back in in the tank, but wasnt sure if the cap would allow this :(

 

Hi ho hi ho... its off to the scrappy to find a small tank i goooooo :D

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Made it out of what??? Looks like a toilet roll holder from a public loo :D

 

Good work tho! :thumbs:

 

Close.... off cut of square guttering down pipe, perpex end plates, recycled bracket off the supra i removed when fitting the FMIC, and the top bit off the old tank so the cap still fits :D

 

Managed it without a fairy bottle or sticky back plastic though :cool:

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That's pretty cool actually. Where are you mounting it?

 

Next to the battery, in front of the washer bottle neck.

 

Fits quite well, after i did it first time round and realised i couldn't close the bonnet as it sat too high - DOH :D

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a man after my own heart, it really makes me laugh when i see peeps paying £40 or £50 on this board for an expansion tank, mine cost £2, good job fella

 

Id much rather get stuck in and build/fix something myself, none of my previous cars have ever been to a garage in their life :cool:

 

Lovely as a shiney ally tank would have been, i cant spend upwards of £50 on one, as you say!

 

Second bit of bodging/modding for the day: Induction Heat Shield: (made from an old sheet of ally i found in the barn, that used to be attached to the back door to stop our great dane eating his way out...)

 

http://www.streetmodified.co.uk/sm/attachment.php?attachmentid=489&stc=1&d=1241273347

 

Excuse the zip tie... i've yet to think of a good solution for holding the induction kit up!

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It should have one, afraid i went and bought mine from Honda:)

 

Strangely, I was looking into this sort of thing the other day, as the HKS re-mounting of the stock expansion tank to below the o/s headlight, while neat, is not the most convenient place on earth. What variety of Honda does that tank come from? Looks like an ideal size/shape!

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Strangely, I was looking into this sort of thing the other day, as the HKS re-mounting of the stock expansion tank to below the o/s headlight, while neat, is not the most convenient place on earth. What variety of Honda does that tank come from? Looks like an ideal size/shape!

 

Heres the part numbers i used when i bought mine which was not that long ago, it also comes in White not Black.

 

Its off a Civic and i made my own mounting bracket, i also cut and removed part of the battery tray as it was just a smidge to high as i fitted mine right next to the battery.

 

19106-RNA-A00 JOINT

19101-RNA-A01 TANK

19102-RNA-A00 CAP

19103-RNA-A00 HOSE INSIDE THE TANK

DSCF0878.jpg

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