Hi,

I’m fairly certain my heater core is leaking. No wet floor mats, but strong coolant smell when running the heater and lots of windshield fogging. I don’t think it’s picking up the smell of the tiny coolant leak in the engine bay.

I took a look at some manual, pics, and vids. All the replacement cores come with prefab piping. Could I cut this piping at the core and put a small rubber hose on it to connect to the existing piping in the dash? This would prevent me having to take out a ton of dashboard stuff.

Has anyone done this or a similar approach?

Thanks!

 

I can give a conditional “maybe” as an answer for you.

See, the thing is that originally the heater cores came in 3-4 parts: the core, the piping until the firewall, the O rings to the pipes and some kind of clamps. If you have an original heater core from 2005 (or so) you can remove the heater core and that’s that. No need to mess with the pipes.

Now, sometime later on (subsequent model years, I think applies to D4 mostly?) the heater core and the pipes started shipping as one integrated unit. I mean, the pipes to the firewall were welded on.

If you get a Nissens aftermarket heater core, the core and the pipes will be separate (see next post with images). You do not need to use the new pipes but instead the old ones will fit “perfectly” the stubs on the new core.

 

here are some pictures for you. Since you’re in North America (I assume) note that the WIDTH with the measurement tape is in SI units (centimeters) NOT in imperial units. 😎🙈

 

Thank you!!

I figured there had to be some easier way to do this. If I can source a heater core that’s just the core (pipes not attached like in your pic), I should be in business. It’s just a matter of crimping the core around the existing pipes.

I think I saw a Nissens model on AB…

Thanks again!

 

I’m genuinely curious how much you need to remove to swap the heater core at a bare minimum, feel free to share your story and some pictures 🤩

 

I may be in the same boat. I think my core may have a super tiny leak, not sure. But I should just do mine anyway cause of age. And what kajtzu posted is spot on and very helpful. There are some threads about doing the core with taking very little out. Search and you will find, I dont have them handy now. I think one process may require some cutting of the inner dash assembly but its not a big deal.

But to answer your original question about cutting and using hose. Of course, that is not an issue at all and I think folks have done that as well. The cooling system is only 16psi max. And the factory itself uses plenty of rubber hoses to attach pipes, including several small sections of rubber to joint the very long pipes going to the rear HVAC core. The issue is that ideally you have some sorta flare on the end to prevent the hose from slipping off. That can be done by putting a screwdriver inside and working it in a curricular motion. You dont need much of a flare.

 

So far, the leak appears minimal. Someone was already in there, and I see some dried up red along the core’s seams. Levels don’t drop too much, and I think the leak in the engine bay needs more attention than the core.

Besides, I’m having so much fun driving it! I don’t wanna put it away just yet.

I’ll post back when I go for it.

 

A friend replaced his by cutting a small square out of the plastic trim near where the AC drain tube is and was able to remove the core without removing anything else, if you do it neat enough no one would be any wiser.