W126 heater core swap - PeachParts Mercedes-Benz Forum

Hit Man X · #1 07-02-2007, 11:13 PM

Since I'm doing my evap core in the 300SEL here, I am going to go ahead and do the heater core...

Now, is there any reason to replace those aluminum hoses from the core to the monovalve?

cdplayer · #2 07-03-2007, 09:26 AM

Quote:

Originally Posted by Hit Man X

Since I'm doing my evap core in the 300SEL here, I am going to go ahead and do the heater core...

Now, is there any reason to replace those aluminum hoses from the core to the monovalve?

OOOOOOOOO.....That's a job that gonna require alot of patience. I took a W126 dash apart to get a core just to have as a spare. Parts were half off at Pic N Pull then. Couldn't pass up the deal. But never had to actually
do the repair and replace.

As for the hoses, my guess is if there is no evidence of a leak, probably not. Good luck.

Hit Man X · #3 07-03-2007, 10:05 AM

Nah, it's not that difficult of a job... just time consuming. People blow things out of proportion quite a bit online who have no business getting that deep into a repair.

Hell, I can do 617 oil lines in 90min start to finish with a new motor mount installed and a starter in less than two hours...

wscheffer · #4 07-03-2007, 06:40 PM

I just got done doing my 420 SEL where I replaced the evaporator core, expansion valve and dehydrator. It was very time consuming and as I took it apart I labeled wires and put bolts and nuts along with other goodies into lunch bags and labeled them too. This helped in putting it back together.

I did not change the heater core since these hardly go when cooling system is maintained properly. I did change all the bulbs in my instrument cluster though.

86560SEL · #5 12-17-2008, 02:52 AM

Just for future reference incase I ever have the pleasure of a failure - how difficult is it to replace the heater core in a W126? Entire dash removal like on the W140? I was thinking it was not as involved as the W140, but from what I am making of this thread it is.

Why do car companies have to make these so difficult to get to anyway?

Back in 1996, my uncle had to replace one in his wifes 1985 Ford Thunderbird and the entire dash had to come out and what was even worse on this one is that it had the digital electronic cluster.

When the HC went out on my mothers 98' Oldsmobile Achieva the book said entire dash had to come out, but the shop said he did not have to remove the entire panel to change it.

compu_85 · #6 12-17-2008, 03:02 AM

I just did one in my ex 1991 Jetta, yes the dash had to come out but it's not really that big of a deal. Just time consuming. (FWIW the reason it failed was probably green coolant)

How much is a new heater core? If its cheap you may as well do it while you have the dash out.

-Jason

S-Class Guru · #7 12-17-2008, 01:47 PM

The classic heater-repair madness was the early-70's Olds Cutlass. You had to remove the RIGHT FENDER to get to the heater core or fan.
Easier than a 140 dash though I would think.

DG

86560SEL · #8 12-17-2008, 09:40 PM

Quote:

Originally Posted by S-Class Guru

The classic heater-repair madness was the early-70's Olds Cutlass. You had to remove the RIGHT FENDER to get to the heater core or fan.
Easier than a 140 dash though I would think.

DG

No doubt. I had a 1969 Chevrolet Caprice that had a new heater core installed and I found out on that car too that the RF fender had to come off to change it. NOTHING on the dash had to be touched.

david s poole · #9 12-18-2008, 11:07 AM

in all my yrs working on benzes i have never seen a heater core leak.they are made of metal not plastic like american iron.maybe it has something to do with the weather in germany.you can always roll the windows when warm but when it gets cold you cannot survive without a heater.

pawoSD · #10 12-18-2008, 06:19 PM

They're not entirely metal, the upper and lower portions are plastic, just like a radiator....