Tomorrow i will be replacing my radiator, just wondered if anyone has any tips, as never replaced one before, guessing i remove fans and disconnect bottom hose to drain fluid.

Then replace radiator and refill? Any advice would be great its for a 1998 classic

 

Hi,

I've done a few radiators, only problem I've had is the hose clips falling apart. I replace them with stainless steel jubilee clips.
Changing the radiator is super easy to do

 

Do a search in my username, I recently posted a full "how to" on refilling the system without airlocking.......follow carefully, if it airlocks, THERE IS NO KNOWN WAY TO BLEED IT!

Be careful with the small pipe on the left of the rad, if snapped off, it's a new rad, again.

I'd be inclined to remove the upper and lower brackets and Hammerite both before fitting the new one...they rust terribly. Refit all with new stainless bolts.

 

alcazar has done a great thread on refilling the system. As far as I remember the rad and fans come out together,then put the fans on new rad and replace

 

Just remember to unplug the fan/fans.

 

Agree with the clip comment, i had to swap mine for jubilee clips in the end as the old ones just didn't grip again, better do it right first time!

 

Sweet cheers for help, so only real worry is getting an air lock, should I need the whole system?

 

I'd be inclined to swap the top hose too....manipulating it opens up tiny cracks inside which then form pinholes to the outside. Use new, DECENT Jubilee clips.

Not sure of your meaning above?

 

I think most people have covered the main bits. I would get the top and bottom plates powder coated if I did another one before fitting.

As for the stainless hose clamps make sure you use ones that are not perforated as these chew up your hoses. JCS high grip are good as are mikalor.

Don't over tighter the bleed screw if it's plastic end caps as I have had the threaded part it screws into crack before.

And as per the others fill slowly in the correct manor to avoid airlocks.

 

Are there any step by step guides on here as can't find any

 

We have a subaru mechanic friend of the family, retired now, but worked at the same dealership for 40 years, a lot of that time as a subaru dealership.

I asked him the other night what the subaru practice was regarding refilling the coolant, and he said they bleed up like any other system.

I mentioned this site and that a lot of people are struggling to re fill the coolant, and when i pushed him further he suggested slowly filling through radiator cap (highest point) allow it to bubble, fill further, start engine allow to tick over and just keep adding coolant every time it 'burps', and top the expansion tank to mid point.

But he didnt consider the impreza to be problematic to re fill with coolant.
And he says he never needed to fill from anywhere other than the radiator cap.

 

Well lucky him...he seems to know not much if he thinks it can be bled

Jaygsi: search is your friend. As I said in my first post, do a search in my username....first post I find having used my username and "coolant" as a keyword, produces the following thread: https://www.scoobynet.com/general-te...-question.html

It's about third or fourth post.

HTH

 

I spent 10 mins searching your name found nothing lol

Can't you bleed them from the bottom of radiator?

 

Air rises in fluid.... you can't bleed anything at the bottom. It's not just air here its all the little water ways in the block and various pipes etc that trap air.

As for the guy who says Subaru's are not problematic... Maybe if you don't really care about getting airlocks they are easy. But if you don't want potentially damaging airlocks I would follow the widely known practice of filling to avoid airlocks. Your choice.... I will keep to doing it a way I know works and avoids airlocks.

For the record this is what I have done for eight years:

Disconnect top hose (rad end) and slowly fill engine through top port until full.
Reconnect top rad hose.
Disconect the small hose that goes from the H/T to the rad (highest point of rad) at the rad end.
Fill Via H/T whilst keeping finger over the hose, when coolant comes out the rad pop the hose back on.
Continue to fill via the header tank untill a couple of cm from the top.
Fill expansion tank.
Massage top and bottom hoses to get air bubble out.
With rad cap left of, set the heater and fan controlls to medium and start car.
Allow the car a few mins for hot air to start to come through the fans, keep checking for this as you keep an eye on the level in the header tank and top up a little when required.
Massage top and bottom hoses to get air bubble out.
As the hot air is now coming through the fans, and the level in the H/T is stable with no air bubles be expelled, its safe to put the rad cap on.

 

Ok cheers bud, that sounds straight forward enough even for me, when you say H/T you mean header tank?

 

Yeah as in the tank attached the the inlet manifold with the radiator style cap. Expansion tank is the little plastic one behind the nearside headlight.

 

Don't shoot the messenger, i thought i was doing folks a favour by asking someone who was trained by subaru.

I shall now disregard everything he has told me on your assumption he 'knows not very much' after all he was only in the trade for 40 years.

You stated in a post that the system can't be bled, but don't know why, you also seem then, not to know very much either.

I don't know either way, but i know i bled mine up and i doubt subaru would design a cooling system that, to quote you 'can't be bled'

As you were..

 

I think Alcazar means that the Subaru radiator ISN'T fitted with any bleed screws, which you could otherwise open out after the coolant has got up to temp., to allow any trapped air to escape.

I think that's what he means by "it can't be bled".

Instead, as above, you have to remove the header tank cap and fill up via the h/t neck, or even better, via the coolant hose which goes to the turbo (using a funnel and an uninterrupted flow of water/coolant mix till full).

 

Thanks Martin for taking the time to ask, its handy to have as much input as possible.


I will follow your instructions FMJ cheers, just another question, doesn't matter how i remove radiator? As in order of pipes etc just as long as fit new radiator in way described?

 

Not really, just undo and remove the brackets, dissconnect all hoses and the fan wires and pull it out .

 

1. It can't be bled bcause there are no bleed points/screws. How's that?

2. How, EXACTLY did you bleed yours?

Stop being childish and taking the hump.....Subaru mechanics don't know everything, some have done AWFUL things to cars, detailed on here.
And yours hasn't been on Subarus 40 years...trust me.

 

Cheers for all your help guys all seem to go well new radiator fitted. Had a leak couldn't find where was coming from in the end my mate found loose pipe. Will double check water tomorrow make sure all ok

 

If you guys think filling Subaru's with Coolant is hard you should try it on some BMW's, and they have bleed screws!!

I've done mine twice now and never had a problem, I just fill the rad to the top through the cap, then the rest straight through the turbo tank, no pulling hoses off etc, fill it right up, run the engine with the cap off until the stat opens with the heaters on full hot, let the air come round and bubble out, top up when required, check you've got hot air out of the heaters, fans kick on and off as required. Job done.

 

Good luck doing that on a classic.

 

Lol was thinking the same. As with most things there are ways you can do things that may "work" but I would rather avoid potential issues by doing things the established way.

 

Fair point

 

I've always back filled it.......works for me!

 

Just checked water level gone done a tad so topped up all looks good.