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Thu Jul 02, 2009 6:50 pm

So it's been bothering me that the fan doesnt come on as soon and as consistently as I would like, so I got a new switch. Now my question, any tips for getting the thing in?

Thu Jul 02, 2009 6:58 pm

Have the system at least moderately cool and make sure the pressure is relieved by loosening and retightening the cap. Make sure the gasket is in place on the new switch and then unscrew the old making sure the gasket comes off with it. Quickly insert and tighten the new one so you loose little coolant in the process.

Run and replenish coolant any lost coolant. Bleed if you think you need to.

If you are running a stock 87° thermostat, you may be happier with a XXX-75 fan switch.

Thu Jul 02, 2009 7:05 pm

Yeah, not quite sure which thermostat I've got. Got the fan switch from Van Cafe, there was only one option, so I took it. I'll probably do the thermostat at some point later, but fan switch for now.

Thu Jul 02, 2009 8:31 pm

If you find that your fan still doesn't come on as much as you want buy this one. It is available at many FLAPS as well.

http://busdepot.com/details.jsp?partnumber=25195948175

Thu Jul 02, 2009 10:36 pm

I was able to change mine without losing any significant coolant. Maybe a quarter cup. Pull the old one slowly, and when it's just about to pop out, pull it out quickly and cover the hole with your thumb. Get the second one ready and quickly make the switch. Should be fairly straight forward.

Thu Jul 02, 2009 10:48 pm

Sure enough, that was a piece of cake. I was thinking it'd be a bit more difficult...
Thanks for the tips, I imagine that would be pretty disastrous were the coolant at all hot.

Mon Aug 31, 2009 10:58 am

could someone please break down the differences in the 3 different radiator fan switches that come up when I search on Bus Depot. Here are the different titles/descriptions for the different switches that will fit my van.

Radiator Fan Switch

95-90c

Raditor Fan Switch

3-point, low temp version, 75-70/82-77c

Radiator Fan Switch

Stock, 3-point, 85-74/93-82c

Thanks for the info everyone! 8)

Mon Aug 31, 2009 11:17 am

Two different switches were used on waterboxers, with the 1.9 switch running at higher radiator temps than the later 2.1 switch. The 3rd much lower temp switch is from a different VW/Audi vehicle.

The first of the 2 numbers is the radiator temp that makes the switch turn on and the second number is the temp it turns back off at. There has to be some difference between the on/off temps or the thing would switch on/off like crazy. So 95-90 means - on at 95, off at 90

When there is a second set of 2 numbers it means it is a 2 speed switch.
85-74/93-82 means 85 is low speed on, 93 is high speed on

Using too low of a temp switch can cause problems, notably for A/C equipped 86-91 models. The lowest temp version turns on high speed at a lower temp than the stock switch for those years turned on low speed. Since high speed also disables the A/C people with those years may have no A/C a lot in hot weather.

On 82-85 models using the lowest temp switch can cause damage over time to the fuse panel. The fuse for the fan can overheat and melt the plastic that holds the spring clips for the fuse. It is not a lot of fun to replace those early fuse panels but repairs can be done by moving the fan fuse to a separate fuse holder and VW makes holders that attach to the end of the panel.

Mark

Blix wrote: could someone please break down the differences in the 3 different radiator fan switches that come up when I search on Bus Depot. Here are the different titles/descriptions for the different switches that will fit my van.

Radiator Fan Switch

95-90c

Raditor Fan Switch

3-point, low temp version, 75-70/82-77c

Radiator Fan Switch

Stock, 3-point, 85-74/93-82c

Thanks for the info everyone! 8)

Mon Aug 31, 2009 11:30 am

crazyvwvanman wrote: Two different switches were used on waterboxers, with the 1.9 switch running at higher radiator temps than the later 2.1 switch. The 3rd much lower temp switch is from a different VW/Audi vehicle.

The first of the 2 numbers is the radiator temp that makes the switch turn on and the second number is the temp it turns back off at. There has to be some difference between the on/off temps or the thing would switch on/off like crazy. So 95-90 means - on at 95, off at 90

When there is a second set of 2 numbers it means it is a 2 speed switch.
85-74/93-82 means 85 is low speed on, 93 is high speed on

Using too low of a temp switch can cause problems, notably for A/C equipped 86-91 models. The lowest temp version turns on high speed at a lower temp than the stock switch for those years turned on low speed. Since high speed also disables the A/C people with those years may have no A/C a lot in hot weather.

On 82-85 models using the lowest temp switch can cause damage over time to the fuse panel. The fuse for the fan can overheat and melt the plastic that holds the spring clips for the fuse. It is not a lot of fun to replace those early fuse panels but repairs can be done by moving the fan fuse to a separate fuse holder and VW makes holders that attach to the end of the panel.

Mark

Blix wrote: could someone please break down the differences in the 3 different radiator fan switches that come up when I search on Bus Depot. Here are the different titles/descriptions for the different switches that will fit my van.

Radiator Fan Switch

95-90c

Raditor Fan Switch

3-point, low temp version, 75-70/82-77c

Radiator Fan Switch

Stock, 3-point, 85-74/93-82c

Thanks for the info everyone! 8)

Thanks for the excellent reply crazyvwvanman. Which switch would you get if you were me? I am thinking the 1st one listed 95-90 would be the default and best way to go, would you recommend running the 3rd one listed (stock, 3 point, 85-74/93-82)?

Mon Aug 31, 2009 11:39 am

I use the 2.1 version 3 point 85-74/93-82 switch, in all models.

Mark

Blix wrote: crazyvwvanman wrote: Two different switches were used on waterboxers, with the 1.9 switch running at higher radiator temps than the later 2.1 switch. The 3rd much lower temp switch is from a different VW/Audi vehicle...............

Thanks for the excellent reply crazyvwvanman. Which switch would you get if you were me? I am thinking the 1st one listed 95-90 would be the default and best way to go, would you recommend running the 3rd one listed (stock, 3 point, 85-74/93-82)?

Mon Jul 14, 2014 1:16 pm

Wildthings wrote: Have the system at least moderately cool and make sure the pressure is relieved by loosening and retightening the cap. Make sure the gasket is in place on the new switch and then unscrew the old making sure the gasket comes off with it. Quickly insert and tighten the new one so you loose little coolant in the process.

Run and replenish coolant any lost coolant. Bleed if you think you need to.

If you are running a stock 87° thermostat, you may be happier with a XXX-75 fan switch.

Ok Im giving CPR to this thread because I have a question about getting the old switch out... I keep looking for what tool was used to loosen and then tighten the radiator fan switch...

Is it that simple that no one mentions it?

Mon Jul 14, 2014 1:21 pm

anyone know which switch for a totally stock 82 1.6NA diesel?
(yeah I know it's slow...)

I'm about to tear into the cooling system and would like to get the right one!
Jeff

Mon Jul 14, 2014 1:30 pm

Neptuno wrote:
Ok Im giving CPR to this thread because I have a question about getting the old switch out... I keep looking for what tool was used to loosen and then tighten the radiator fan switch...

Is it that simple that no one mentions it?

I can't remember if I used a deep socket, box or open end wrench, but it was nothing special. It should be obvious when you need to do it, straight forward and simple.

Mon Jul 14, 2014 1:38 pm

PDXWesty wrote: Neptuno wrote:
Ok Im giving CPR to this thread because I have a question about getting the old switch out... I keep looking for what tool was used to loosen and then tighten the radiator fan switch...

Is it that simple that no one mentions it?

I can't remember if I used a deep socket, box or open end wrench, but it was nothing special. It should be obvious when you need to do it, straight forward and simple.

Maybe the reason Im searching is that mine is an 85 and that the switch sits low on the drivers side of the vanagon like this one

Mon Jul 14, 2014 2:19 pm

Get a deep 30mmm socket or a deep 1 1/4" socket.

Mark

Mon Jul 14, 2014 2:28 pm

crazyvwvanman wrote: Since high speed also disables the A/C people with those years may have no A/C a lot in hot weather.

Hmmm...
I noticed recently a couple of things that really make a difference in the A/C running.

I normally wear a bra on front with the Big Tube bumpers and have a winch blocking the airflow to the radiator.

Taking off the bra made a difference in air flow. It ran a little cooler.
Moving the winch to the rear receiver also made a difference in cooling.

The biggest thing I noticed is once the high speed fan kicked in the whole system ran very cool. The air conditioner would blow colder air than when you were on the highway and you could see it on the temp gauge. It would run down in the 170-180 range when shot with an IR gun on the radiator.

So for some reason mine still cycles and runs the compressor even with the fan on stage 2? :idea: Bra-less seems to be the way to go when it is hot!

Mon Jul 14, 2014 2:32 pm

Your van has 3 fan speeds. The rad fan speed #2 is turned on by the A/C when freon pressure is high and yes max A/C should then be available. Speed #2 is pretty high and loud. The highest fan speed #3 is turned on by the radiator temp switch when the radiator is too hot. Then the A/C compressor clutch is also disabled.

Vanagons have radiator fans with 2 fan speeds triggered by 2 temp switches in the radiator, low and high. Most use a dual switch with 3 wires to it. Early vans used 2 separate temp switches. 86+ with A/C have a middle fan speed that is only controlled by the A/C.

Mark

Syncro Jael wrote: crazyvwvanman wrote: Since high speed also disables the A/C people with those years may have no A/C a lot in hot weather.

Hmmm...
I noticed recently a couple of things that really make a difference in the A/C running.

I normally wear a bra on front with the Big Tube bumpers and have a winch blocking the airflow to the radiator.

Taking off the bra made a difference in air flow. It ran a little cooler.
Moving the winch to the rear receiver also made a difference in cooling.

The biggest thing I noticed is once the high speed fan kicked in the whole system ran very cool. The air conditioner would blow colder air than when you were on the highway and you could see it on the temp gauge. It would run down in the 170-180 range when shot with an IR gun on the radiator.

So for some reason mine still cycles and runs the compressor even with the fan on stage 2? :idea: Bra-less seems to be the way to go when it is hot!

Mon Jul 14, 2014 7:26 pm

I found these switches and part numbers:

1. Operating temps 75/82C Product Code: 251.959.481.75 (167º/185º F)

2. Operating temps 85/93C Product Code: 251.959.481K (185º/199º F)

3. Operating temps 95/102C Product Code: 951.606.481.00 (203º/216º F)

These were on Pelican Parts for Porsches, but the part number 251.959.481K is identical to the one I just purchased from Van Cafe for a 1987 Syncro. Low speed on at 185º / High on at 199º :?:

So at what temp does the REALLY HIGH speed come on? Or am I just all screwed up now :shock:

http://www.paragon-products.com/Radiator-Fan-Switch-p/251.959.481k.htm

Mon Jul 14, 2014 7:40 pm

Syncro Jael wrote: I found these switches and part numbers:

1. Operating temps 75/82C Product Code: 251.959.481.75 (167º/185º F)

2. Operating temps 85/93C Product Code: 251.959.481K (185º/199º F)

3. Operating temps 95/102C Product Code: 951.606.481.00 (203º/216º F)

These were on Pelican Parts for Porsches, but the part number 251.959.481K is identical to the one I just purchased from Van Cafe for a 1987 Syncro. Low speed on at 185º / High on at 199º :?:

So at what temp does the REALLY HIGH speed come on? Or am I just all screwed up now :shock:

http://www.paragon-products.com/Radiator-Fan-Switch-p/251.959.481k.htm

The switches have only two speeds low and high, the middle speed comes on with the AC IIRC.

Mon Aug 04, 2014 10:56 am

crazyvwvanman wrote: Get a deep 30mmm socket or a deep 1 1/4" socket.

Mark

Does it gush a lot once its out? not knowing that is keeping me from doing this