Heater core replace or by pass ??

[bobe]

Took my car out of storage. I turned on the heater and the interior filled with a mist of coolant. How difficult a job is to replace the heater core or is it better to by pass it. Car only driven in summer. It's an '84 844.

Thanks

[earlr85944]

bypass it if you dont use it, its a PITA

[Razorback1980]

I agree...it's a PITA. There is a pipe that runs along the side of the cam tower and into the firewall. There is also another pipe that runs out of the firewall but I can't remember off the top of my head where it runs but I think to the back of the hot water valve. To bypass the heater core, run a hose from the metal pipe by the cam tower to the location the other hose coming out of the firewall goes to. That's all there is to it. You may want to look just to make sure the hoses connecting to the firewall are not leaking...may not be the heater core.

[cauzomb]

The other connection is on the head under the manifold by the firewall, be very carefull with that little plastic vacuum switch on the heater collant elbow. It's a chore to replace the heater core! it's behind the center console, under the dash below the HVAC blower......

[88BlueTSiQuest]

Originally Posted by bobe

Took my car out of storage. I turned on the heater and the interior filled with a mist of coolant. How difficult a job is to replace the heater core or is it better to by pass it. Car only driven in summer. It's an '84 844.

Thanks

I just finished doing a heater core on my '83. First question, does your car have A/C? Mine did.

1. Remove center console.
2. Remove dash board.
3. Remove A/C box, this requires disconnecting A/C lines, so have it discharged first.
4. Remove hood above blower motor. This might require you to loosen the bolts mentioned in step 6 to gain clearance.
5. Remove blower motor. Steps 4, 5, 6 and 7 are performed in the engine compartment.
6. Remove the 4 bolts surrounding the blower motor opening.
7. Disconnect heater core hoses from engine (1 hose on the passenger side on the pipe, the other hose at the back of the intake manifold).
8. Pull heater assembly away from firewall, to disconnect hoses.
9. Pop off heater core cover, and slide out heater core.

Install is the reverse.

If tackling this job, I highly suggest all new hoses and heater valve, at the very least, replace the hoses and valve that lead to the core (3 hoses total).

Core is pretty cheap, ~$50 at Advance Autoparts. Just ask for a Heater core for an '83 VW Rabbit w/o A/C. Any VW motor available, as the important part is lack of A/C.

[88BlueTSiQuest]

Originally Posted by Razorback1980

I agree...it's a PITA. There is a pipe that runs along the side of the cam tower and into the firewall. There is also another pipe that runs out of the firewall but I can't remember off the top of my head where it runs but I think to the back of the hot water valve. To bypass the heater core, run a hose from the metal pipe by the cam tower to the location the other hose coming out of the firewall goes to. That's all there is to it. You may want to look just to make sure the hoses connecting to the firewall are not leaking...may not be the heater core.

Given the fact that the valve actually stops all water flow. I wonder if you couldn't just disconnect and remove that pipe, and plug the water pump outlet there.

Then plug the pipe outlet on the back of the intake manifold. That outlet might even be totally removable, as it was a T type connection IIRC.

Getting rid of that pipe would make a cleaner appearance under the hood, for those that don't require a heater core at all.

I didn't really look into any of this, as my '83 will be serving winter duties, so the heater core is needed.

[bobe]

The hose going into the the heater core from the heater valve was leaking.
I replaced it and the clamp and the problem seems solved.
Thanks to all for excellent advise...as always.

[mikepellegrini]

Hey Bobe - I'm going through this same thing on my 83 NA right now. The hose from the heater valve to the firewall, or the valve itself is leaking.

I've got the intake manifold off so I have good access, but I can't see how I can get at the hose clamps from the engine side. I haven't taken off the rubber grommet that the two hoses pass through the firewall in - I'm afraid I would destroy it trying.

A comparison of the old hoses to the new ones suggest there's probably an inch to 1 1/2" of each hose on the wrong side of the firewall.

How did you get to the clamp on the heater valve/firewall hose without remvoing the dash and all?

A pic of the hoses and the grommet:

[mikepellegrini]

Bump

[bobe]

The hose clamp was loose and coolant was running down into the core or something like that. Anyawys, I tightened the clamp at the engine block and that solved the misting problem. I never had to tackle anything more than that.

[mikepellegrini]

Thanks. I guess I'm grasping at straws. The thought of having to pull the dash and all that crap just to replace two hoses is kinda daunting.