24 replies to this topic

[Johno]

Ive tried running normal hose water pressure through each side of the heater core hoses but can’t get it to come out the other side no matter which side I put it in.

I have turned the heater on in the dash but I’m not sure if it’s actually turning the heater on and opening up the inlet and outlet.

How could I tell if that heater mechanism has opened or if the core is blocked?

I’m concious ofhow delicate the core is so don’t want to push it.

[limo]

What car? Generally heater cores are constant flow unless external tap. Not that delicate, similar to radiator. I've taken them to radiator guy and he removes end tanks and rods the tubes to clean. Then resolders the ebds back.

[Johno]

LX 4 door. There’s no flow whatsoever between inlet and outlet.

Should I just delete it at the water pump for now?

[Johno]

Is this a good way to delete it for now:

 

 

Attached Files

•  Delete.png   613.17K   16 downloads

[hanra]

Is that your engine bay?

[Johno]

Haha I wish. My car is yellow but that's where the similarity ends. I saw this one on carsales.

[hanra]

So you’ve shoved a hose up the copper pipe of the core where it comes out the firewall?

[Johno]

Hanra, no I shoved the hose in the hose that goes into the copper pipe in the firewall. Only reason is becuase it's easier to access. But I think I'll try going straight into the copper pipe and see what happens. I just figured short of the hose being clogged (unlikely) it's the same thing. But it could be that when I pull the hose off the copper pipe, the copper pipe is visibly coroded and blocked.

[Johno]

Update:

I pulled the hoses off and flushed it directly at the inlet on the heater core. This provided flow through the outlet. I then reverse flushed it by running the hoses through the outlet and got water coming through the inlet. So I then put the houses back on and did the same thing however it seemed a bit restricted when reverse flushing through the outlet.

I thought to check there wasn’t any leaks behind the dash and lie and behold, I have green coolant dripping below where the heater core sits. It would appear I’ve put too much pressure through it and broken it.

Is it typically ok to back flush these things?

How hard is it to remove the heater core? Where’s the best place to get one from that’s good quality?

[claysummers]

If mains water pressure is enough to rupture your heater core I had a limited life anyway. You could look for a serviceable used one or go cap in hand to old school radiator shop for a recore.

Sent from my SM-G781B using Tapatalk

[Johno]

Would one from rare spares be ok?

[hanra]

I imagine the core is subject to the same 13psi that the rest of the cooling system is. So Im sure your hose couldn’t of exceeded that. Has someone shoved a plug up inside your hoses as they knew the core leaked?

My RSP heater core is still working.

Edited by hanra, 03 December 2022 - 07:54 PM.

[warrenm]

Most town pressure is something like 60psi, which is well above 13-15psi that a cooling system usually is, so that has the potential to rupture a heater core.

[Johno]

From what I’ve read the original heater cores are 7 PSI. With this in mind I only used household water pressure, maybe even less - as opposed to using a jet connector on the hose.

Not sure what the rare spares ones are rated.

Strangely I could get it flush through both inlet and outlet (backflush) at the firewall but when I then flushed it with the hoses attached I could barely get any flow.

Another wierd thing I got the core to flush to clear water but the water that’s leaking inside the dash is coolant green.

Edited by Johno, 04 December 2022 - 12:20 AM.

[Rockoz]

Even when I had a VB Commodore the radiator place told me that the heater cores were only 7 lb.

I got a 13 lb core installed instead of buying a new 7 lb heater core from the dealership.

Think it cost me 5 bucks extra for them to give me the 13 lb over buying a replacement.

 

Cheers

 

Rob

[Bruiser]

I disconnected mine so long ago that I can’t fully remember if or how bad it leaked
Blew down a hose the other day, some water still came out!
Mucky brown though, at least yours was green

[Johno]

Oh it was brown during the flush but green dripping into the car. As if just a back portion of the heater core was leaking and somehow separated from the brown stuff

So to get a 13 PSI one, the only way is to get mine rebuilt from a radiator shop as a 13PSI?

Or can I purchase a new 13PSI from somewhere?

[Rockoz]

Probably easiest to get your old one rebuilt.

But it is pricey these days with the cost of brass and copper.

 

I can remember buying radiators for around the 100 buck mark many moons ago.

Was quoted 850 for a similar sized radiator recently.

Went alloy instead.

 

Cheers

 

Rob

[Johno]

Probably easiest to get your old one rebuilt.
But it is pricey these days with the cost of brass and copper.

I can remember buying radiators for around the 100 buck mark many moons ago.
Was quoted 850 for a similar sized radiator recently.
Went alloy instead.

Cheers

Rob

Are you referring to a radiator instead of a heater core?

[Bruiser]

This got me looking at prices for these
One for my commode (Torries similar prices) on eBay
around $130 and up.
Rob must be talking about radiators.
I’ve just been here too and bought an alloy rad after being
quoted $750ish for a copper brass type
Maybe drop in to your local natrad shop and get the lowdown
On the best way to go with it

[hanra]

What’s wrong with one of these?

https://www.rarespar...ith-58-34-pipes

[308 Sunbird]

^^^^^ Nothing! Job done.

[hanra]

Be aware there are two types with differing outlet sizes. 

[Rockoz]

I was talking about radiators.

But the idea was to give an idea of how much more expensive it is for copper and brass.

 

Cheers

 

Rob

[Bruiser]

The eBay ones show the same picture as the rares one, just a few bucks cheaper