www.gt4dc.co.uk
Maintain, Modify and DRIVE your GT-Four


It is currently Sat Jun 23, 2018 10:55 pm




Post new topic Reply to topic  [ 17 posts ]  Go to page 1, 2  Next
Author Message
PostPosted: Sat Jul 08, 2017 3:09 pm 
Offline
New Poster

Joined: Wed Apr 05, 2006 12:47 pm
Posts: 28
Location: south wales
Car Model: None
Hi need some help with a over heating/fan issue on a ST205
i belive the problem is the fans as when driving the cars temps are fine
if the car is stationary in traffic the temps rise quite sharply

i know there are set things to check this, so id like someone to go through these step by step
im no mechanic but im competent at fixing things, so bare that in mind with any replys
as i would need basic instructions, including the location on any sensors that need un-plugging/checking

thanks in advance


Top
 Profile  
 
PostPosted: Sat Jul 15, 2017 2:38 pm 
Offline
New Poster

Joined: Wed Apr 05, 2006 12:47 pm
Posts: 28
Location: south wales
Car Model: None
know one at all got any advise or help?


Top
 Profile  
 
PostPosted: Sat Jul 15, 2017 3:22 pm 
Offline
Club Staff
User avatar

Joined: Wed Jul 13, 2005 12:14 am
Posts: 3222
Location: Camberley, Surrey
Car Model: ST205
Are the fans actually running? If you leave the car idling do they come on after a while?

_________________
GT4DC Events Co-ordinator
1996 ST205 UK


Top
 Profile  
 
PostPosted: Sun Jul 16, 2017 9:12 pm 
Offline
Group B
User avatar

Joined: Sat Sep 02, 2006 3:13 pm
Posts: 3599
Location: Bournemouth
Car Model: None
For some reason I missed this in the view active topics list until today.

To test the fan system, unplug the fan switch on the bottom of the radiator and the fans should run all the time with ignition on (The switch is normally closed and opens when hot).

It does sound most like fans not working, but there are other possibilities. If the heater goes cold when idling / overheating check the following:
- It's not unknown for the water pump impeller to become detached from the shaft leading to poor circulation.
- Check the coolant is full in the radiator (not the overflow tank). Headgasket failure is rare on the 205 but cracked blocks aren't unknown. If it keeps blowing coolant out then it could be a sign.

_________________
If at first you don't suck seed, try drier grain.

Image


Top
 Profile  
 
PostPosted: Sun Sep 10, 2017 12:30 pm 
Offline
New Poster

Joined: Wed Apr 05, 2006 12:47 pm
Posts: 28
Location: south wales
Car Model: None
sorry for the delay as ive been away working im back now so now able to except help!

basically as asked, the fans are non functional, meaning they do not come on at all
is this a fan issue or could id be sensor related?
are both fans connected? as in, if one fails the other will not work also?

my main concern is diagnosing the problem correctly, so i can replace the parts that need replacing
and not working my way through parts that (might) be faulty

so i appreciate any/all help and advise


Top
 Profile  
 
PostPosted: Sun Sep 10, 2017 3:42 pm 
Offline
Club Staff
User avatar

Joined: Wed Jul 13, 2005 12:14 am
Posts: 3222
Location: Camberley, Surrey
Car Model: ST205
Nibbles will be able to advise better but I would imagine the first step is to establish if this is a mechanical or an electrical problem.

Get the multimeter out and a spare car battery - see if you can power up the fans via the disconnected plug. One of the fans only normally runs when the AC is on as far as I remember.

_________________
GT4DC Events Co-ordinator
1996 ST205 UK


Top
 Profile  
 
PostPosted: Sun Sep 10, 2017 4:25 pm 
Offline
New Poster

Joined: Wed Apr 05, 2006 12:47 pm
Posts: 28
Location: south wales
Car Model: None
Thanks, maybe worth a mention with regards to the fans, ive had the AC removed sometime ago
are you saying that only one of the fans actually keeps the Rad cool? or have i missunderstood


as far as sensors go, id have to have exact location, to make sure im checking the right one
i believe its lower bottom right of the rad fans (facing the car)?

or is this in the relay


Top
 Profile  
 
PostPosted: Wed Sep 13, 2017 1:49 am 
Offline
Group B
User avatar

Joined: Sat Sep 02, 2006 3:13 pm
Posts: 3599
Location: Bournemouth
Car Model: None
The sensor that runs the fans is on the bottom tank of the rad nect tp the exit hose. Unplugging this should make the fans run constant with ignition on as this feeds a normally closed relay.

There is also a pressure switch on the aircon plumbing near the diagnostic connector which activates a fan if disconnrcted, It's possible this was removed with the aircon then the fans disabled to stop them running constantly.

Anyway, try unplugging the sensor to confirm whether ir's a sensor issue.

_________________
If at first you don't suck seed, try drier grain.

Image


Top
 Profile  
 
PostPosted: Wed Sep 13, 2017 9:25 pm 
Offline
New Poster

Joined: Wed Apr 05, 2006 12:47 pm
Posts: 28
Location: south wales
Car Model: None
Big thanks for the info, with regards to the Air con

this was removed quite some time ago, the Fan issue is only recent

i will check advised over the weekend and report back on monday


Top
 Profile  
 
PostPosted: Fri Feb 09, 2018 7:57 pm 
Offline
New Poster

Joined: Wed Apr 05, 2006 12:47 pm
Posts: 28
Location: south wales
Car Model: None
Sirius wrote:
Nibbles will be able to advise better but I would imagine the first step is to establish if this is a mechanical or an electrical problem.

Get the multimeter out and a spare car battery - see if you can power up the fans via the disconnected plug. One of the fans only normally runs when the AC is on as far as I remember.


have done the fan test, connected both fans to battery and both fans do run
im assuming that its a fuse or possible sensor issue, what to try next?


Top
 Profile  
 
PostPosted: Sat Feb 10, 2018 4:00 pm 
Offline
New Poster

Joined: Wed Apr 05, 2006 12:47 pm
Posts: 28
Location: south wales
Car Model: None
have also disconnected the lower rad sensor as advised

both fans do run constant, so fans are all good

is this just a replacement of the sensor in the rad (as seems)?
or maybe fuse issues? I can get these checked but would need to know what
fan fuses to check and exactly what to check for (I wont be doing this, so need full instructions)


few questions before I get any reply's, will any celica 6 gen rad sensor do or is it ST205 specific
as i don't have the part numbers to cross reference, also is the sensor a screw-in type
or will it need some form of sealing as in Plumbing tape

also a used item good enough if working or should I buy new?

would be great to have some help with this now/over the weekend as ive got the time
and the car is up on stands, although I know the rugby's on later


Top
 Profile  
 
PostPosted: Sun Feb 11, 2018 12:11 am 
Offline
Group B
User avatar

Joined: Sat Sep 02, 2006 3:13 pm
Posts: 3599
Location: Bournemouth
Car Model: None
If the fans run when the sensor is unplugged, then there is nothing wrong with the electrical part except for the sensor itself.

It is possible the sensor is also ok, and the problem is a lack of water circulation at low speed.meaning the bottom of the radiator stays cooler. If you put the heater on full and see if it goes cold when idling for a period, this would indicate a water pump problem or a low coolant level. You could also try feeling the temperature of the bottom radiator tank when idling, or better still measuring if you have an IR surface temperature meter or a thermocouple.

If you change the sensor, from memory coolant will escape while it is out so do it with the engine cold and make sure pressure is released first. With care, you should be able to quickly swap them without losing a huge amount of coolant.

_________________
If at first you don't suck seed, try drier grain.

Image


Top
 Profile  
 
PostPosted: Sun Feb 11, 2018 12:45 am 
Offline
New Poster

Joined: Wed Apr 05, 2006 12:47 pm
Posts: 28
Location: south wales
Car Model: None
Thanks for the reply, with regards to you questions
I don't have any problems with the heaters, also the rad does (warm up) to operating temperature all over
I know it cant be ruled out, but the water pump is also quite new 10k miles

I did have a issue with the coolant level dropping under the marker on the (bottle/tank) so maybe this
has caused a failure in the sensor?

also per my last post, is the sensor ST205 specific? or will any 6 gen part do

ive recently flushed the coolant in the rad, so this can be re-done when fitting the replacement sensor


Top
 Profile  
 
PostPosted: Sun Feb 11, 2018 10:37 am 
Offline
Group B
User avatar

Joined: Sat Sep 02, 2006 3:13 pm
Posts: 3599
Location: Bournemouth
Car Model: None
I'd be very surprised if the GT4 sensor is different but I can't say for certain.

If it were me, I'd be ringing TCB to order a new one, then it will be right. www.tcbparts.co.uk

_________________
If at first you don't suck seed, try drier grain.

Image


Top
 Profile  
 
PostPosted: Sun Feb 11, 2018 1:00 pm 
Offline
New Poster

Joined: Wed Apr 05, 2006 12:47 pm
Posts: 28
Location: south wales
Car Model: None
Nibbles wrote:
I'd be very surprised if the GT4 sensor is different but I can't say for certain.

If it were me, I'd be ringing TCB to order a new one, then it will be right. http://www.tcbparts.co.uk


Thanks, the sensor does seem to be the route of the problem

unfortunately having a serious issue with buying non fitting brake parts from TCB
and my dealings with Paul, I vowed never to spend another penny there, which is a shame
as ive spend ££££ with them in the past and always found trevors service to be 100%

so ill be looking elsewhere


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 17 posts ]  Go to page 1, 2  Next


Who is online

Users browsing this forum: No registered users and 6 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group