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Mon May 17, 2021 11:51 am

So back in October, my fan wouldn't turn on, so I jumped the plug until I got a new fan switch. When I jumped the plug, it wouldn't work on low speed, only high speed. Installed a new fan switch, and it would only work on high speed.

A couple of weeks ago, I bought a new resistor, with the understanding that it would fix the low speed issue, but the first time I took the van for a long enough drive to get up to temp, the fan didn't come on at all, and it sprung a leak.

So now the leak is fixed, but the fan doesn't turn on (coolant system is bled). It can be jumped on either low or high speed. So the question is, do I just need a new fan switch again, or is the resistor still suspect? The timing of the failures and lack of functions just seems odd...

Mon May 17, 2021 12:01 pm

In case it matter, what year is your Vanagon[ I'm assuming '86 or later due to actually having an external resistor for the fan vs my older 2 speed model with internal resistor.]

Mon May 17, 2021 12:09 pm

Have you attempted to touch the switch as the engine warms up? The switch needs to get to temp for it to work. The gauge and the switch are completely independent. You could have a circulation problem.

Mon May 17, 2021 1:52 pm

jlrftype7 wrote: In case it matter, what year is your Vanagon[ I'm assuming '86 or later due to actually having an external resistor for the fan vs my older 2 speed model with internal resistor.]
It's an '87.

I haven't tried touching the switch, but I will, that's a good idea. It would be JUST WONDERFUL to have to replace the water pump or something else after spending all day Saturday cursing at the thing while I was replacing hoses and installing SS coolant pipes (figured it was time, not related troubleshooting the fan).

Mon May 17, 2021 1:56 pm

Hybrid VW wrote: jlrftype7 wrote: In case it matter, what year is your Vanagon[ I'm assuming '86 or later due to actually having an external resistor for the fan vs my older 2 speed model with internal resistor.]
It's an '87.

I haven't tried touching the switch, but I will, that's a good idea. It would be JUST WONDERFUL to have to replace the water pump or something else after spending all day Saturday cursing at the thing while I was replacing hoses and installing SS coolant pipes (figured it was time, not related troubleshooting the fan). You could buy an Infrared Thermometer too, it's handy to point and take a reading of different areas that you're trying to diagnose for engine and coolant systems.

Amazon has lots of them...

https://www.amazon.com/s?k=infrared+thermometer&am...-doa-p_1_4

Mon May 17, 2021 2:14 pm

It’s likely not the actual water pump. Short of an infrared temp gun, you can learn a lot with your hand. I can tell you, you won’t be able to hold the rad fan switch if it is getting to its operating temp.

Mon May 17, 2021 2:52 pm

I'd have to agree with all the aboves, but I also have to ask, with all that you were 'up to' on that coolant system work, did you flush the radiator? If so, did you take a look at what came out? And my next thought starts out the same, but ends in; and you didn't replace the radiator?

Well, I have had a radiator waiting for 'that day' for a long time, so I am not disrespecting you here, just asking.

Mon May 17, 2021 3:04 pm

If your Vanagon has (or had) factory air conditioning, or if it is a syncro model, then your Vanagon has the three-speed radiator fan system. This system uses a combination of resistors and relays to allow both the rad temp switch and the AC system to switch on fan speed 1, 2 or 3. The wiring diagram for that can be found in this link:

http://faculty.ccp.edu/faculty/dreed/Campingart/vanagon/87vanagonschmatics/simple87coolingfanwac.gif

If, however, your Vanagon is not a Syncro and never had factory air conditioning, then you have the two-speed fan. This system does not use a separate resistor. The wiring diagram for that system can be found in this link:

http://faculty.ccp.edu/faculty/dreed/Campingart/va...annoac.gif

The difference between the two systems is that in the A/C or Syncro vans, the rad fan is designed and wired to permit three speeds, whereas in the rest, the rad fan only supports tow speeds and neither speed is controlled by or affected by a resistor.

Tue May 18, 2021 6:45 pm

bobbyblack wrote: I'd have to agree with all the aboves, but I also have to ask, with all that you were 'up to' on that coolant system work, did you flush the radiator? If so, did you take a look at what came out? And my next thought starts out the same, but ends in; and you didn't replace the radiator?

Well, I have had a radiator waiting for 'that day' for a long time, so I am not disrespecting you here, just asking.
Definitely feels like a flow issue. I can touch both hoses leading out of the thermostat housing towards the front of the van with no issues when the coolant is up to operating temp. Likewise, the stainless pipes feel like they barely have any temperature to them

As far as flushing the radiator, I guess I SHOULD have, but the thought didn't cross my mind. I was having SO much fun with everything else eating up my day, that I may not have had time to "finish" the project if I had R&R'ed it.

I have an appointment to drop the van off on Friday to install Powerflex bushings, so it looks like the shop is going to get a little more work than we originally planned on :wink:

Wed May 19, 2021 8:58 am

Hybrid VW wrote:
I have an appointment to drop the van off on Friday to install Powerflex bushings, so it looks like the shop is going to get a little more work than we originally planned on :wink:

Holy smokes! That sounds cool. I've done a few of my powerflex bushings, not the full job yet tho... I can't imagine what a shop would charge. "two 10 hour days" was the response from a guy who did the full job one weekend on his own. I'm sure it would take me a week.

Wed May 19, 2021 6:33 pm

bobbyblack wrote: Hybrid VW wrote:
I have an appointment to drop the van off on Friday to install Powerflex bushings, so it looks like the shop is going to get a little more work than we originally planned on :wink:

Holy smokes! That sounds cool. I've done a few of my powerflex bushings, not the full job yet tho... I can't imagine what a shop would charge. "two 10 hour days" was the response from a guy who did the full job one weekend on his own. I'm sure it would take me a week.
Yeah, I'm not really looking forward to the bill, but I've got some slop to get rid of, and I don't have the time to do the job myself right now, so....