Blower Motor

Replacing the heater blower motor

I've now had the pleasure of doing this job on 3 different cars: a '70 144, a '68 145, and a '74 164. The 164 is fairly similar to the 240 series. This has given me enough knowledge to use some shortcuts to get it finished quickly, and enough cynism that I can't help but wonder what evil mind at Volvo decided to build up the car around the blower motor.

Budget about a day to do this job (no, I'm not kidding). If you're about to buy a car that's "fine, you'll just have to fix the blower", it's a good point to get several hundred off the price.

There are some aftermarket fans available with better bushes - they'll last longer. It might be worth considering one of those to save you from having to do the job again someday. The fan I bought for the 164 had a sealed housing as opposed to the open cage units Volvo originally used, so hopefully it'll outlast the rest of the car.

On the 140/164, There are 2 basic types of fan: A round one on top of the heater matrix (early types), and the so called "combined unit" which is similar to the later 240 unit, and which has a motor with 2 fan wheels in front of the unit.

Safety and keeping your car intact:

As you'll be working in the car, around the fusebox (140), and removing and replacing parts of the electrical system, disconnect the battery to make sure you can't accidentally short-circuit anything.

There are 2 ways to do this job: removing the entire unit, and trying to remove only the fan. The latter is fairly easy on the combined unit, a bit harder on the early model. You'll be working near the heater unit and/or moving it around, so PLEASE don't do this when the engine is hot, to avoid the danger of getting hot coolant over you or the car. Check the hoses to the heater matrix (they're located at the back, between the heater matrix and the firewall) for integrity. If they're bad, cracked or dried out, you'll have to replace them anyway so now would be a good time to drain the cooling system.

The combined unit has the airconditioning matrix (if AC is fitted) integrated. Please be careful not to remove the AC plumbing if the AC is charged. If you have the remove the AC plumbing, have the AC discharged by a certified AC shop.

Oh, and keep some band-aids ready, as you'll quite likely cut yourself on some piece of metal you hadn't noticed was hidden in the dark behind the dash.

The job at hand:

Your first decision is whether to remove the entire unit or just go for a fan swap. The former is more work, but has the advantage that you can check and clean the entire unit, heater matrix et cetera. The latter is quicker, and you needn't drain the cooling system.

Early unit: Begin by removing the large plastic panel under the dashboard, as it's in the way. Pull it from it's clips that keep it attached to the dashboard to give it some movability. Move it around so you can undo the two screws that hold the choke cable to it's metal tab, and move the choke cable and panel so that it comes free from the choke cable. Check if the panel is screwed to the heater matrix or fuse box and, if so, remove those screws. Remove the glove compartment and undo the nut that's now the last thing to retain the panel. Take the panel out of the way.

You'll now see the heater assembly, consisting of (from top to bottom) the blower motor (grey roundish housing), heater matrix (beige rectangular housing), and a plastic moulding to which several hoses connect. On very early units the latter two are in fact one single unit. 3 control cables attach to this assembly (thermostat, windscreen flap and floor flap). Although Volvo recommends you disconnect everything, it's possible to leave them attached and save yourself some trouble getting them back on, if you've decided just to replace the fan. Be careful not to damage them while manouvering the various parts around.

Disconnect the blower motor from the blower switch, Undo the 4 (2 on very early units) big air hoses from the moulding, and take off the flexible drain tube on the underside of the moulding (hard to reach). If you've decided to take out the entire unit, disconnect the 3 control cables and the water hoses as well.

Undo the 2 screws that hold the fusebox to the heater matrix, and the 4 screws that hold the heater matrix to it's supports. Keep an eye on the various cables and brackets that are also held by these screw. Move the fusebox out of the way. Take off the clips that hold the moulding to the heater matrix. You should now be able to lift the heater matrix slightly and move the moulding forward, so that there's about 2 inches of free space beneath the heater matrix. Be careful with the thermostat assembly that's sandwiched between the moulding and heater matrix housing. You can now lower the matrix slightly. Very early units can be tilted (lower edge towards the back) and lowered slightly as well. If you've decided to go for complete removal of the unit, you can now slide out the thermostat assembly and tilt/lower/pull the unit free towards you. On the very early units the thermostat is more firmly embedded in the unit, so you'll have to remove the control valve from the firewall (remember to remove the hoses on the engine side of the firewall) and take that out as well with the unit.

Now we're getting close. Undo the clips that hold the blower motor to the heater matrix, carefully pull down the heater matrix as far as it'll go (you'll need approx 1.5 to 2 inches). Watch those hoses that connect the heater matrix to the cooling system ! Carefully wiggle out the blower motor from between the dash and the heater matrix.

Combined unit: I'm assuming you're only replacing the fan here. Complete unit removal is described in Haynes, as is the below procedure. I don't know why Haynes is so keen to remove the instrument binacle, I didn't find it to be a hindrance so I left it in place. Remove the center console side panels, the crash pad under the glove box, the glove box support bracket and the glove box. Remove the screws that keep the center console in place and carefully pull the center console forward to gain more working space. Remove the vacuum lines from the right and left demister nozzles. Remove the air ducting coming from the unit to the demister and floor heater nozzles (it's in the way). Remove the clips that hold the left and right outer casing panels to the unit casing. Remove the clips that hold the right and left fan blades to the spindles. Disconnect the wiring from the fan switch. If all is well you should now be able to remove the 3 screws that keep the fan retaining collar in place, and remove the collar and fan. If you have and identical or rebuilt fan, you can now continue putting it back together again. If you have a sealed unit (which has a bigger body), get out your trusty Dremel (tm) or hacksaw and start modifying the housing to fit the new unit.

Start the rebuilding by getting the strongest vacuumcleaner you can find and vacuuming out all the leaves and dirt that has collected in the heating system over the past decade or two. Carefully replace the blower motor and connect it to it's switch. From here on assembly is the reverse of disassembly as described above.

The first time I did this, on the 144, on a cold february sunday, it took me a full day. The second time, the 145, I was doing a major refurbishment of the vehicle and had done a lot of disassembly already. The 164 took me about 5 hours, including a run to the DIY superstore to buy me that Dremel I'ld promised myself if I ever needed it.

Good luck and drive safely.