Changing out Heater Core in 1971 240Z

[bobc]

Hey sorry if this should be in another area, but didn't seem to fit anywhere else. Can you change out the heater core in a Series One 240Z without taking out the dash? Can you remove the core from the whole unit with the unit still in the car? Anybody that's done this, got any suggestions?

I've read the manuals and it doesn't look like any fun!

Bob

P.S. Antifreeze is dripping off the core inside the unit and leaking out of the box on both sides. It's a small drip, but I think this is only the beginning of a big leak!

[Arne]

Yes, it can be done. Start by removing the cardboard glovebox. Then remove the heater fan motor, and then the heater fan housing. With all that out of the way, you can disconnect the heater box from all the ducting and control cables, unbolt it from the tunnel and firewall, and pull it to the side into the passenger foot well.

[BD240Z]

I've read the manuals and it doesn't look like any fun!

QUOTE]

It's not any fun!

For me, replacing the heater core is the least desirable job on the whole car. When replacing the core, consider replacing all the hoses, clamps and the valve while you're in there. If the job is done properly, you shouldn't have to fool with it again. Removing the seats will allow you more room to manuever around.

Good luck.

Bruce

[mlc240z]

what Arne said, although i found i didn't have to remove the glove box.

[justaZcarguy]

My next door neighbor John has a parts car with 240jetjoc and I was helping take the dash out since I have done this too many times now. Once we removed the dash, I went on a quest to get the core out just for the heck of it.

Call me sick, yes.

The process is tedious, and you have to be somewhat of a contortionist to do it, but it can be done. Beware taking it to a shop, the book calls for around 8 hours to do it and most mechanics get impatient and may not treat the car with some "tlc" like you would.

The heater box HAS to come off the firewall like Arne said, there are 2 screws in the back of the unit that are not possible to get to otherwise.

Do yourself a favor and replace the heater control valve while you have it out. If you have a problem getting this there is a replacement part that you can get from Mack truck that I am told works and is only about twelve bucks new. Please do NOT get the mack truck dog and place on hood, this is NOT a good idea.

In the event that you want some pics of the box out of the car, I can shoot some pics for you so you have an idea what holds what to what, I have found that this has helped me in the past.

By the way, there are 4 cables coming off the dash controls to the box, not three so you know.

Be careful driving the car with this ailment, the cores start to leak quickly and I have heard many a nightmare of warping a head "limping " the car home...

That gets expensive quick.

Let me know, I'll do what I can to help.

Good luck...

[bobc]

Brian,

Yes, please either post or PM any pictures you think will help. It's been a long time since I took apart the interior of a Z, so I could use the help. I've been studying the manuals and prepping mentally to get this done...sure wish I didn't have to!

Bob

[george71z]

I did mine without taking out the dash, so it is possible. Since I'm getting too damn old to be playing contortionist in a Z, I took out the passenger seat and put a piece of 3/4 plywood on the supports. A bit easier on the back. Also have a good trouble light available so all the hidden screws can be found.

[justaZcarguy]

I'm happy to snap some pics for you, it may be this weekend as my damn job has me runnning at 100 mph.

I need a break, I think that I would rather be helping you pull the damn core verses going to work and that is sad at best.

Will Saturday work?

Glad to help...

~Brian

[bobc]

Brian and all,

Saturday or whenever for the pictures is convenient for you is great! Thanks.

George, thanks for the advice on taking out the seat. I think I'll do that too.

BTW, all, the green Z in my profile is not the car with the problem. That's my 1970 and it is such a sweet car that just loves to run, I couldn't let my other trouble maker besmirch her reputation!

Bob

[Ramses]

I had to take my dash out to get the heater core out. When I finished installing it I realized I forgot to replace the heater control valve...Oops, so I had to loosen the dash and do what Arne said, it was slow and tedious. I am tall and did not use a piece of wood to sit on, but that sounds like a good idea.

[ChrisA]

May I suggest when you pull the blower housing out that you replace the seal on the square flange that mates to the underside of the cowl box.

See white arrow on attached picture.

Chris A.

[EScanlon]

http://www.classiczcars.com/forums/showthread.php?t=21508

2¢

E