Help replace heater core Volvo 670

have fun--its not a nice job--only did it once--actually it might not be too bad ,but i had to do it after somebody else took it apart and left it--soo had to figure out how it all went--lots of screws and clips
but sorry----i have no tips or tricks

 

Lol.. just bypass it. For now. Winter almost over. It is a pain in the rear.

 

it is not so easy stuff. Climate unit (not controll unit) is locaed under pass side dash panels. To remove panel, remove passenger's entrance handle first.

Later I'll find manual and post you here.

 

get a quote from volvo-then just pop the side of the pax dash and see if it is worth it
i have no idea what book time would be on it--but it really isnt user friendly

 

This is location of climate unit. Heater core, a/c core, blowing fan, temperature door and air direction doors are all in this unit

 

These are cake for me. I've done maybe 30 of them in the last 2 years. Tip1 remove the speaker from the dash on top (2 screws after you pop the grill off) Under the speaker is a 10mm Bolt you need to remove. Make sure you get both speaker wire connections.

Pull the top bolt from the grab handle and pull the handle to the rear for clearance.

If you truck has the package tray under the dash that goes from side to side remove that Its 5 T25 screws, the last one is hidden under the cup holder. Pull the floor mat back and get the 2 plastic nuts at the bottom of that panel, 10mm socket. under those plastic round covers going up the left side of that panel is a couple more screws and one on top. Now gently wrestle that whole piece out.

Now you should be looking at the housing pic that got posted. you will see little metal clips that hold the bottom half together. Pull the clips closest to the front, about 7~8, of them and pull the lower front cover off toward you. Right in front of you is the blower motor, slide it out and unplug it. Inside the box on the right are 2 aluminum tubes going up. The one closet to you has the heater control valve in it, they run up to the heater core. Pull the 3 air ducts sitting on the top of the heater box. Slip fit and easy to do.

The heater box is made from 4 pieces. You have the front off and now you need to remove the top. The top band the runs all the way around the box and fastens to the firewall on both side has to come off. 2 bolts and 2 screws, 1 each per side. It has to come off for hand clearance.

Next the top of the box comes off and its held on with clips like the front is. And there is 3 or 4 on the back side next to the firewall. I use a pocket screwdriver to get these off.

Once the top is off its heater core time. looking up from the bottom of the core on the right you will see 2 metal clips one on each tube. these hold the tube in place so it doesn't leak. STOP! did you put the heater hose clamps on to block the coolant from leaking. You put them on the hoses outside the cab. Takes 2. when you pull those clips out the core is free to be removed.

**TIP2** You can't get the front clip out without taking the whole box apart. I use a right angle die grinder with a carbide burr and cut a slot about 1/4 inch wide and an inch long to slide the clip in and out. Seal that slot up when you are done with duct tape and whatever you like.

TIP 3 Get a long handled needle nose pliers so you can push up on the front tube to get the clip to slide in. When you go to the dealer make sure and get both Orings as well as the core. The core does not come with the Orings They put all the parts back on.

 

I found manual about this. But unfortunatly it is Russian version. Now I try to find english version of manual. Tip #2 they describe there.

Ouh yeah!


It is not all. There is H-tube under the hood. It is pressure limiting valve. If it fails, no heat. But never drive truck w/o this valve. Heater core may easily be blown with coolant pressure at high engine speed, over 1700 RPM.