Thread: Heater core leaking

Hi Scott.
I did mine several years ago. Its a '95 model. Involved complete dash removal. A full day. I replaced the core with a custom made copper unit. Yeah cost around $300, but I don't want to be doing the job again.
All the best, hope this helps.

Originally Posted by sjane

Hmm, seems to be a bit of info around on changing heater core on D1 update, but how about the early D1? Mine is '92 and although not getting wet feet at the moment, the occasional sweet smell and puff of steam on the windscreen is enough to tell me the heater core is giving way.

Has anyone changed one of these? If so could you please share your story? I'm not sure whether to attempt it (new core is $150 on eBay) or just bypass.

I'd really like to have a heater given its the middle of winter.

Many thanks,
Scott.
'92 Discovery 3DR 3.5 LPG

No need to take out the whole dash. I changed my heater core recently (95 Disco). Just need to remove all the support stuff from the driver's side footwell to expose the core - cut through the aluminium lines (drain the system first is a good idea - I already had mine bypassed and had flushed with clean water so the fallout is not an issue) then pull out the old core. When refitting prefit the bits of hose that attach to the core but do not tighten fully, you can swivel them when loose to avoid the dash supports etc - when its all back in, use heater hose with new clamps to reattach the lines. One thing good to do is go the hardware store and get some self adhesive foam insulating strips to make the core a tight fit in the assembly. I've seen cores range from $175 to $225 - make sure the o-rings are included as they are expensive. There are a few good sellers around of this stuff, mine came from Tasmania. Do a search on this site for more step by step instructions on this relatively easy fix. Takes about 6 hours for a novice. I've had no leaks and it saved a lot of money and time. Good luck.

It seems all the info available is for the >94 Disco, which is somewhat different to the original series 1 with 3.5 V8. Heater core is apparently copper rather than aluminium, and removing the console and facia still doesn't allow me to see whats happening.

Thinking I may just have to bypass the heater all together.

One more question, can anyone tell me if there is a tap or valve in the heater circuit inside the car? Just trying to think of any other possible leak source if I do decide to buy parts.

Cheers.
Scott.
'92 Discovery 3DR 3.5 LPG

I believe your heater closely resembles that in the '92 RRC. My friend has done one. Not impossible but a lengthy process nonetheless.

I did mine last weekend in a 1990 RRC, only took 10 hours!!!!!!!!!!!!! It was the most pain in the bum job I have ever done on the car in the last 12 years, I only fixed it because I moved back to Melb from WA and was freezing in the mornings. I used a brass heater core out of an 85 RRC that I had tested. When I finally demolished the whole dash to get to the heater, I found that mine had an aluminium core with plastic tanks crimped on the sides similar to modern radiators but a bit of careful cutting of the heater/fan box with the Dremel allowed me to get the brass core in - all toasty now. But seriously if the Disco is like the Rangie and you live somewhere that is usually warm I would not bother fixing it. Good luck
Cheers
Nick

Just done mine the pre update series 1 disco you do have to take the dash out. unbolt the heater box from fire wall you then can cut the box instead of splitting it (take your time it is clear with some thought). it takes about 6-8 hours.

I gave up on the idea. Ended up getting hold of a Maruenu car heater (as used in hot rods etc where no stock heater exists. Its a small cylindrical heater core with fan in the middle, quite neat and compact. I put it forward in the passenger foot well with hoses routed along the firewall and through a wiring grommet I found on the drivers side. Not as powerful as the stock heater, but warm enough, and this location means some of the warm air is picked up by the recirc inlet for windscreen defogging. An hours work and no risk to the questionable/unlabelled wiring circuits that have been added over the life of the disco.

If I ever get bored one weekend I might attempt the dash out job, but for now this does the trick.

One question just out of interest, anyone know where that hose goes after the heater core? Just wondering if a heater core were to block up (or be deliberately capped off) what would miss out on water flow? Seems to head off towards the top of the engine.

Cheers,
Scott.