A few weeks ago, I asked here for advice on replacing my mechanical fan with an electric model. I thought I would share my experience, now that it is complete. Volvos don't have enough room behind the radiator for a puller fan, so I had to pick a pusher for the front of the radiator. I purchased a 12" Perma-cool fan. Perma-cools only come as a puller, but they say the fan can be reversed and used as a pusher. The instructions were terrible, they said I had to remove a allen head screw to reverse the fan - they didn't bother saying where the screw was - and there were no pictures. I figured the screw would have to be on the shaft and tried for hours feeling around inside the hub of the fan trying to find this screw. I finaly gave up and exchanged this fan for a model 130 from Flex-a-lite that already came as a pusher. The Flex-a-lite comes with a shroud and it fits almost perfectly. I just had to saw a couple of small grooves in the top of the shroud so two pieces of sheet metal from a supporting brace could fit in. The shroud fits tight verticaly, but there are about 2 1/2" of unshrouded radiator on each side. Also, because of the tight vertical fit, the shroud did not push up against the radiator like it was designed to do.
I was concerned about the unshrouded area, and the possibility of air escaping around the shroud because of not being pressed up against the radiator. So, I tested it by covering all the areas on the front side of the radiator that could leak air with duct tape, leaving the only access for air through the fan (the duct tape was not in contact with the cooling fins of radiator, it just created a perfect shroud). When tested with the duct tape on, it took 36 seconds to cool the car from 185 to 175 degrees (the on and off settings of the adustable thermostat that I chose). When I took the duct tape off, there was no difference - still 36 seconds, so I decided not to worry about the unshrouded area.
I am very pleased, it only comes on if I sit for a while with the engine running. I will say that it is a bit noisier than I would like, but it is acceptable.

I'm interested in how the fan fits.

Paul

Tom-
Thanks for that report- I'm going to add an electric fan to my Amazon to help deal with the inevitable and unavoidable NYC traffic I'll be stuck in this summer. What model Flex-a-lite did you use? Did you use one of their thermostats?

Anyone have comments on mounting? Is it a big no-no to mount 'through the core' as a lot of these aftermarket add-on fans seem to instruct?

I'm going to poke around a local junkyard and see what I can come up with, but suspect I'll end up just ordering something new to put on 'the Bird.'
Tom
NYC

I used the Flex-a-lite 130. It is the same as the 110 except that it is a pusher instead of a puller. It looks like the single fan pictured below. I bought it from Summit Racing for $130. It comes with very nice mounting hardware that worked perfect for my volvo. I just had to drill four holes in the two panels on either side of the radiator. The mounting kits have brackets that reach over the remaining exposed radiator to these panels, almost as if they were custom made. I opted to buy stainless bolts to mount the brackets instead of the plastic hardware provided. The fan also comes with the through-the-core mounting, but not only is not a good idea, but in this case it wouldn't work because the shroud cannot be pressed against the front of the radiator because of a lip of metal that hangs down from the panel above the radiator. Like I said before the fit is very tight, verticaly.
The 130 comes with an adjustable thermostat, that was not difficult to install. I think adustable is the way to go for the thermostat, you can adjust for any inconsistancy in installation or application. The Flex-a-lite thermostat has a sender that you run through the upper hose to the tank. The Perma-cool model that I returned had a sender that you stuck directly into the radiator core - another reason I didn't like it.
The installation is a lot easier with the radiator removed. The radiator is easy to take out. I was puting in a new radiator anyway. Even though I have a B18 engine, I put in a radiator for a B20, so I would have an overflow tank. So, I have a completly revamped cooling system now.
Tom

Tom O wrote:

.....The Flex-a-lite thermostat has a sender that you run through the upper hose to the tank.

I'm having a difficult time visualizing this. Could you expand this a bit?

John and Phil gave a pretty good description of how the temperature sensor works. The capilary tube is very small, much smaller than the one that goes to the temperature gauage. It is about the size of a 22 guage solid uninsultaed wire. Amazing that they manage to make this tiny wire hollow. I mounted the control on the inside of a fender and ran the tube through the wire cable above the radiator then out to the hose. The fan came supplied with a rubber pad with a slit in it for the tube to go through. The pad is attached to the radiator inlet with vinyl tape, then the hose slides over the the tube and pad. My new radiator had one of those lips on the end of the inlet. I dented this lip slightly so the tube wouldn't get squeezed there. I was hesitant to tighten the clamp very much, knowing there is a hollow tube under it. So at first my hose leaked. I tightened the clamp a little more and the leak stopped, and the sensor still worked.
One more thing, I said before that the job of installing the fan was easier with the radiator removed. Actually, in my case, it would have been impossible to install it with the radiator in place. This is, because of the tight fit of the shroud, it had to be inserted from the engine side. Because of limited access to the front of the radiator, this is probably the case in most pusher installations.

I'm using a similar system on my 142 here in Sydney, Australia. The adjuster has a rotary knob for adjusting the fan cut in/out points. From one side runs the electric connectors to the fan circuit. From the other there is a copper capiliary tube which ends small section of larger diameter copper tube about 2" x 1/8" wide. This last part slips between the flange on the radiator neck and the top radiator hose. The normal hose clamp holds it in place.

I was concerned that the setup might leak, but no sign so far. And there are plenty of them in use, so they must be ok.

On my Amazon, I soldered a male brass fitting in the header tank that would take an electric sender. I'm more comfortable with the security of this system, but the downside is that it isn't simply adjustable. You need to change the sender each time, which is a PITA, plus expensive. Ask me how I know... Having said that, once you get it right, you should never have to touch it again.

Rgds

JohnH

I have the same system on my 1800. There's a capillary tube -- much like the one for the temperature gauge or the heater valve -- with a sensor bulb on it. This slips into the upper radiator hose from the front with the hose removed from the radiator. There's some sort of cushioned collar (memory fails right now) that pads the tube from chafing against the radiator fitting, and the tube is held tight to it with electrical tape. The hose then slips back onto the radiator and is clamped there as normal.

Sounds dubious, but if assembled with a bit of care, it's bullet proof.