Rad fan cooling

for questions and answers about alternative power transplants on the T25, GTi, Porsche,Subaru etc, this is the place. You must register to post but anyone can read.

Moderators: User administrators, Moderators

Post Reply
vwaddict
Registered user
Posts: 219
Joined: 20 Apr 2012, 14:22
80-90 Mem No: 0

Rad fan cooling

Post by vwaddict »

I have a water cooled t25 which was a jx but now has a AGG conversion fitted, my temperature gauge allways sits just over 3/4 even when the jx was still in it, my fan switch comes on at about 76deg so that's OK.
Is it possible that the gauge itself could be faulty? Can this happen??

I doesn't have a relay in the 2nd stage holder tucked away behind the fuse board either? Does it need this??
Air-cooled I'm ok with, water I'm newbie really...
DSC_2094.JPG
(104.13 KiB) Downloaded 203 times

Sent from my E6853 using Tapatalk
1989 devon shuttlebus with reimo interior 1.6jx

vwaddict
Registered user
Posts: 219
Joined: 20 Apr 2012, 14:22
80-90 Mem No: 0

Re: Rad fan cooling

Post by vwaddict »

It's got the 500w fan if that makes any difference...
Last edited by vwaddict on 17 Jun 2017, 23:57, edited 1 time in total.
1989 devon shuttlebus with reimo interior 1.6jx

vwaddict
Registered user
Posts: 219
Joined: 20 Apr 2012, 14:22
80-90 Mem No: 0

Re: Rad fan cooling

Post by vwaddict »

Apologies for the upside-down photo...

Sent from my E6853 using Tapatalk
1989 devon shuttlebus with reimo interior 1.6jx

pw2904
Registered user
Posts: 12
Joined: 25 Aug 2013, 22:16
80-90 Mem No: 0

Re: Rad fan cooling

Post by pw2904 »

I have a JX and mine was doing the same, it turned out to be the incorrect thermostat in mine though? Wonder if this would be the case for you too.


Sent from my iPhone using Tapatalk

vwaddict
Registered user
Posts: 219
Joined: 20 Apr 2012, 14:22
80-90 Mem No: 0

Re: Rad fan cooling

Post by vwaddict »

pw2904 wrote:I have a JX and mine was doing the same, it turned out to be the incorrect thermostat in mine though? Wonder if this would be the case for you too.


Sent from my iPhone using Tapatalk
It's possible, but their 2 different engines?

Sent from my E6853 using Tapatalk
1989 devon shuttlebus with reimo interior 1.6jx

User avatar
marlinowner
Registered user
Posts: 1530
Joined: 28 Jan 2014, 12:02
80-90 Mem No: 13646
Location: Scottish Borders

Re: Rad fan cooling

Post by marlinowner »

The temp gauge uses the temp sender on the thermostat housing, whereas the rad fan uses the temp switch on the rad, so the gauge and rad fan work independently. You may have the wrong sender fitted on the thermostat housing, the one on my Audi derived engine reads in the middle of the gauge, but if I fit my spare gauges, which come from a dg van, the temp gauge reads high.
1993 SA VW T25/T3 2.5i Microbus/homebrew camper
1981/1968 Marlin Kitcar TR6 Engine

vwaddict
Registered user
Posts: 219
Joined: 20 Apr 2012, 14:22
80-90 Mem No: 0

Re: Rad fan cooling

Post by vwaddict »

marlinowner wrote:The temp gauge uses the temp sender on the thermostat housing, whereas the rad fan uses the temp switch on the rad, so the gauge and rad fan work independently. You may have the wrong sender fitted on the thermostat housing, the one on my Audi derived engine reads in the middle of the gauge, but if I fit my spare gauges, which come from a dg van, the temp gauge reads high.
Yes I realise about the fan & gauge work independently , but what I can't understand is how both engines were reading the same?? Could it be the gauge itself? Is there any way of testing it?

Sent from my E6853 using Tapatalk
1989 devon shuttlebus with reimo interior 1.6jx

vwaddict
Registered user
Posts: 219
Joined: 20 Apr 2012, 14:22
80-90 Mem No: 0

Re: Rad fan cooling

Post by vwaddict »

Surprise surprise It turned out to be a loss of earth at the back of the gauge, thanks to the ole blue ribbon....

Thought I'd mention it Just in case anyone else has the same issues..

Sent from my E6853 using Tapatalk
1989 devon shuttlebus with reimo interior 1.6jx

Post Reply