Series 3 V12 Running Hot

SESH · Post by **SESH** » Sat Oct 30, 2010 8:06 pm

Hi, I took the E out this afternoon for a short run as the sun was out ! :)

On getting stuck in some traffic the temperature gauge started to rise and got to about three quarters on the dial. (somewhere between normal and H.) I pulled over and opened the bonnet. With the engine running and also off (with ignition on) the electric fans both weren't running. I think that whilst I was in traffic the heat wasn't dissipating (no fans) and when running at normal road speed the air was cooling the rad. Waited 30 minutes to let it cool down and went home in free flowing traffic :D In your experience as V12 owners what is the most likely cause.

1. Fuse
2. Electric Fan Relay
3. Thermostatic Fan Switch.
4. Something else

Your thoughts and advice appreciated.

Cheers
Mike

vipergts · Post by **vipergts** » Sat Oct 30, 2010 9:54 pm

I'm not an expert except that these fans do have a habit of ceasing when/if the car is not used regularly.

They are a common problem. Might be as simple as a fuse or relay or possibly take them off and service or replace them.

Aldeburgh · Post by **Aldeburgh** » Mon Nov 01, 2010 12:13 pm

I had very much the same issue. My fans were worn out, basically ~ I tried new original-style fans but in the end I asked Harry to instal modern fans activated by a temperature probe which sits in the radiator. Good system, keeps things cool, probably the destination of choice for those not wedded to complete originality.

SESH · Post by **SESH** » Mon Nov 01, 2010 6:35 pm

Thanks for ideas.

As both fans are not running I'm guessing that it has to be a fuse, the relay or the thermostat. It would be highly unlikely to be both fans failing at the same time. Although I tend to agree that a modern alternative to keeping the temperature down would be an advantage. Will need to give it some thought.

Thanks again. Any other ideas welcome.

Cheers
Mike

D COUPE · Post by **D COUPE** » Tue Nov 02, 2010 2:02 pm

One of the things that I was going to do is sort any cooling problems.

and this was the cure. Not cheap Mike but they work really well with a new radiator.

Dave C

SESH · Post by **SESH** » Tue Nov 02, 2010 4:55 pm

Dave, that looks like a serious piece of kit!! But probably serious money, what is it and how much ?

Cheers
Mike

PeterCrespin · Post by **PeterCrespin** » Tue Nov 02, 2010 5:06 pm

Look up Mike Frank's Coolcat Corp site. He has info on which VW (Golf?) fan to install in the standard mounts as he only does Coolcat fans for the sixes IIRC.

Easy enough to jump the relay connections and/or temp switch and see if they come on.

D COUPE · Post by **D COUPE** » Tue Nov 02, 2010 5:38 pm

Hi Mick

My thoughts were if it kept them cool in California then
that was good enough for Me. www.v12s.com

The set up is avaliable a little more local now but when I was collecting parts I was there so I bought one. Hand luggage ?328!

I got it home and thought it would not be hard to replicate using good quality fans that are readily avaliable on Ebay etc etc

I also fitted a kenlowe thermo switch just so I could set the temp myself.

Works a treat in traffic on a hot sunny (rare) day.

I cant tell You how much better I feel with it on...................
This was on the top of My modification list along with a seperate gearbox cooler (auto) to take it out of the radiator so lessen the running temp.

If the V12s have a problem its HEAT so do your best its worth it

Dave C

Post by **Heuer** » Tue Nov 02, 2010 5:58 pm

As Pete suggests: http://www.coolcatcorp.com/V12Fan/V12Fans.html

e.g. http://tinyurl.com/32jfofn

e-bygum · Post by **e-bygum** » Tue Nov 02, 2010 7:32 pm

Mike
Before you start thinking about buying replacement parts let's try to find the fault.
Taking it step by step:
1. Do you have a wiring diagram?
2. Is the fan circuitry as is shown in the diagram or have modifications been made (quite common)?
3. Do the horns work? If yes then you don't have a fuse problem. Go to 4.
4. Connect a wire to Fan Relay terminal w2 and tap the other end on a good earth. Does the Fan Relay pull in? Do the fans run?
If the fans run the fault is in the circuit between Fan Relay terminal w2 and earth - either the wiring, the connections or the Otter switch.
5. Without removing the connections short the otter switch terminals together, with the ignition on the fans should run. If they run you have a faulty otter switch. If they dont run you have a wiring fault.

Let us know what you find and we can take it from there.
Pete

SESH · Post by **SESH** » Tue Nov 02, 2010 7:46 pm

Thanks guys really useful stuff.

Will try the suggested route first, but upgrade certainly worth thinking about. The fans were running ok until a couple of days ago. Also, and I don't know if this is a coincidence, but the main beam is not working and that was working before! Maybe the same fuse?

Will let you know how I get on.

Cheers
Mike

SESH · Post by **SESH** » Wed Nov 03, 2010 1:26 pm

Problem located I think.

The horns don't work. I get a clicking from the relay but no sound so I am assuming that it must be the inline fuse for the horn/fan circuit.

Can anyone tell me where to find the fuse and what Ampage should it be.

Thanks for all your help so far.

Cheers
Mike

e-bygum · Post by **e-bygum** » Wed Nov 03, 2010 1:41 pm

SESH wrote:Problem located I think.

The horns don't work. I get a clicking from the relay but no sound so I am assuming that it must be the inline fuse for the horn/fan circuit.

Can anyone tell me where to find the fuse and what Ampage should it be.

Thanks for all your help so far.

Cheers
Mike

The line fuse is on the top of the right hand side engine frame. I'm not sure of the amperage but think it is 35A.
You really should get a manual if you intend working on the car yourself.

SESH · Post by **SESH** » Wed Nov 03, 2010 4:02 pm

Hi Pete,
Thanks for your help.
I have got a parts and service manual although it's on CD.
Trouble is trying to find the relevant page and diagram !!!

Cheers
Mike

SESH · Post by **SESH** » Wed Nov 03, 2010 11:55 pm

Hi again, sorry to be a pain but I am struggling to find the online fuse for the horn and fan relays. The only inline fuse I can find is just above the battery and it has a fairly thick brown wire going in and out. Can't see any others. Have looked on the top frame and other than the harness block connectors there are no signs of an inline fuse.

Mike

e-bygum · Post by **e-bygum** » Thu Nov 04, 2010 11:04 am

Mike
That's the one, sticking out of the loom with a couple of inches of brown cable on each end on top of the right hand side engine frame. Push the ends together against spring pressure to release the glass fuse.

SESH · Post by **SESH** » Thu Nov 04, 2010 10:54 pm

e-bygum wrote:Mike
That's the one, sticking out of the loom with a couple of inches of brown cable on each end on top of the right hand side engine frame. Push the ends together against spring pressure to release the glass fuse.

Thanks Pete, think we have the problem solved. Fuse replaced and horns working. I haven't run it up to temp yet to test the fans, but as the fuse is on the same circuit it has to be the answer. Only concern is that when I took the old fuse out (it had blown) someone had put a 50 amp fuse in there and it had still blown. I replaced it with a 35 amp fuse. Only hope I haven't got a wiring issue somewhere, time will tell.

Thanks again to all who offered assistance.

Mike

e-bygum · Post by **e-bygum** » Thu Nov 04, 2010 11:30 pm

Mike
If one or both fans are seized/hard to turn they will pull excess current which could be the cause of the blown fuse. Try spinning the fans by hand, they should be very free running. Make sure that everything is off while you have your hands in there and that there is no way the fans can switch on.
I personally would short out the otter switch to test the fans in preference to running the engine.

As I said, I'm not sure of the fuse value. It is possible that it should be 50A.

SESH · Post by **SESH** » Sat Nov 06, 2010 9:00 pm

Fans turning freely. Took it out for a run this afternoon fans working and cutting as they should. Checked the book and it says 35 Amp in the inline fuse holder for horn and fan. Will monitor situation. Still quite interested in that coolcats design using the Volkswagen fans with a two speed setting. Think that the high speed setting can be wired up to the dormant panel switch (heated rear window). Would give peace of mind in the summer.

Thanks for all your help.

Cheers
Mike

SESH · Post by **SESH** » Fri Dec 31, 2010 1:39 pm

Hi, going to go the coolcats route and install the two VW twin speed fans. I've now got the fans (new) bought on ebay for ?27.99 each. The procedure looks reasonably straight forward plus you then have the luxury of increasing the airflow in slow traffic when needed with a manual override switch wired to the current redundant panel switch on the OTS. This is the heated rear window switch on the FHC. Mike

Link:
BBcode:
HTML:
	Hide post links

Link:
BBcode:
HTML:
	Hide post links

Link:
BBcode:
HTML:
	Hide post links

Link:
BBcode:
HTML:
	Hide post links

Link:
BBcode:
HTML:
	Hide post links

The 'E' Type Forum

Series 3 V12 Running Hot

#1 Series 3 V12 Running Hot

#2

#3

#4

#5 the cure

#6

#7

#8

#9

#10

#11

#12

#13

#14

#15

#16

#17

#18

#19

#20