cooling fan 1997 smiley face

[Chug]

IIRC there is some resistor/relay type thing either on the passenger side of the radiator or fitted close to it, we didn't have any diagrams and couldn't figure the wiring out and we ended up fitting a different fan that was wired through the switch on the thermostat

[Diddymus]

Update.... I took the old temperature sensor along with the brass bush that it screwed into Arggghhhh. I used epoxy two part resin to stick the bush back in as the plastic threads were no longer viable (Dam it) anyway new sensor in , no leaks from the bush so far (fingers crossed) ran the engine up to temp and a bit more and the fan still didn't kick in until I removed the harness connector from the sensor then 5 seconds later the fan started...really can't work this out?? pluged it back in and the fan stopped. Could it be something to do with the associated PCM (power control module)
Any ideas would be much appreciated and thanks for all your input so far.
David

[Frag]

Fan is controlled by PCM,unplugging the sensor makes it open circuit.
PCM then runs the fan as a safety contingency.

[Diddymus]

Good morning and thanks FRAG for confirming what I was thinking, so do you think there is a problem with the PCM ?

[Frag]

Not necessarily,
Cooling fan won’t kick it till top end of temp guage,without looking I’d say around 104/108 degrees.
(Thermostat usually opens at 88)
The fact fan kicks in with sensor unplugged,suggests wiring,PCM ,relays and fan are all ok.

It should be 2 speed,running low to start,then high speed if temp still climbs.
Have you tried it since replacing coolant temp sensor ?
Checked both the fuses for high and low speed ?

Is it actually as hot as you think or is guage reading incorrect?
You said you suspect there’s no thermostat fitted,is that still the case or have you now fitted one ?

[Diddymus]

Thanks for you prompt answer FRAG

So I haven't had the thermostat housing off to check the if there is a stat fitted but I do have a new one to fit.

When I take the connector of the sensor then after about 5 secs (give or take) I see the fan start and after a few more seconds it speed up a little more, so I assume anything to do with the fan is in tacked and working then.

I have run the engine up to temp and beyond the normal just past the white indictor for normal ends but not to the red mark on the scale briefly but the fan still didn't come on. maybe I didn't let it go far enough to the red section.

So I will open the stat housing and put one in and run it up to temp again. The reason I suspect there is no stat or its not working is it always runs cold (the temp needle lifts just on scale) when I'm driving around, however when left to idle(say waiting at lights or traffic que then the temp start to increase but as soon as I start driving again it goes back to cold on the temp gauge.

I really appreciate your knowledge and advice.
Regards
David

[Frag]

Certainly sounds like there’s no thermostat in there,or it’s stuck open.
Worth fixing for engine wear,driveability and economy.
The PCM makes all its fuelling and ignition timing calculations based on coolant temp (along with all other input sensors)
And also,every cold start to past 70degrees classes as a ‘drive cycle’ for the adaptive learns of the PCM
So if yours runs cold or never gets above that,it will have knock on effect.

If the fan picks up in speed,that also means both low and high speed relays and fuses are also ok.

Ideally,the right diag machine would test all these things,and you could datalog coolant temp etc:
Fords machine for the ‘95 transit would be FDS 2000.
I’m not sure if anything else newer,even at a Ford dealer will work now on a smiley.

I doubt PCM has failed,they rarely go wrong,and on a pcm that age EEC 5 I think,
A sign of failures/safe mode is constantly running cooling fan,fixed ignition timing
And I think fuel pump would run constant with ignition on also.

[Frag]

You may also find these threads of use;
viewtopic.php?f=10&t=200537&p=1696502#p1696502

viewtopic.php?f=4&t=201059&p=1698077#p1698077

[Diddymus]

Hi Frag , thanks again for this. This is where I'm up to. I took the thermostat housing off and found that the only thing in there was a circular rung with no mechanism (See Pic ) so I took it out and replaced it with a new stat. The engine warms up much better and stays (see pic of temp gauge in cab) doesn't get much hotter and the stat is opening and closing. but the fan still doesn't come on unless I take the connector of the sensor? I haven't run the engine to the red meltdown indicator on the gauge in the cab yet. The outside temp (Ambient) is 7 deg today so took it for a run and the gauge doesn't go much past what the pic shows though I haven't been stuck in traffic or wait long at lights.
I also took a pic of a green lead with connector and can see anywhere for it to connect? I was wondering what this was? anything to do with my issue??? I don't know just clutching at straws here??
Where would I get a fault code reader like you suggested ?
I guess because I haven't yet seen the fan actuate when temp is high I worry it won't work when outside temp is in 20s I'm stuck in a jam and the heat is in the red.

I hope I'm making some sort of sense to you.
Thanks again for your help
David

[Frag]

So the middle had definitely been chopped out of the thermostat.

I wouldn’t worry about that connector,it’s either for something on a different spec vehicle,or some had an ignition suppressor I think on a 1 wire connector.

I’m thinking you may have a faulty temp sensor for the guage.
I’ve never seen a smiley transit temp guage,sit anywhere but straight up the middle when at normal operating temp,so pointing at the ‘R’ in normal.

Also,someone has ‘doctored’ the red section of the temp guage,if you look closely,someone has painted the red block making it smaller,or just completely re-done it …!!!
It should be symmetrical to the white / cold section.

Then I’d expect cooling fan to kick in at the end of the ‘normal’ section / start of the red.
Maybe your guage is just innacurate / overreading, ?
Is that why previous owner ‘modified’ the thermostat ….

So ,cooling fan may be working perfectly,but you’d have to be brave to run it up guage to find out,as it’s showing much hotter than true,it’ll likely be past the red before fan cuts in.
You could do with either a code reader of some sort that can read coolant temp (which will be from PCM)
Or
One of those infra red temp guns ?

[Chug]

I agree it should sit on the R or thereabouts, and the fan should kick in before it gets to the end of the M to keep it around the R, and with a new thermostat fitted we can assume that is working properly ( did you notice if it had a temp stamped on it? ) they are usually in the 88 -92C range, which will be around R on the gauge, so the fault is most likely the temp sensor reading wrong, but this still doesn't explain your fan problem, because where your gauge is sitting past the L it should be on full speed trying to cool back to the R on the gauge.

I've had these engines in the red many times without issue, so I would run it and keep an eye under the bonnet (you can smell/feel when it is getting really hot and switch off) and see if the fan does eventually kick in.

[MinorMatt]

Why not plug the temp sensor you removed in to the harness (loose, not bolted in) and run the engine. Heat the sensor up (boiling kettle etc to start with) and see if the fan kicks in? If (as frag says it won't kick in until 104/108ish degrees you may want to remove from the water and then use a small propane flame/Similar to top it up a bit? If you melt it and the fan hasn't come on you know there is an issue?

Alternatively, now you have put the thermostat in, just drive it and don't worry unless the temp starts showing above the normal marking?

[Diddymus]

Good afternoon everyone So I got my Foxwell Proscan connected to the ODB port located in the fuse compartment( please note this port is not ODBII compliant) but the socket is the same and my scanner has a number of protocols to choose from. Scanner eventually talking to the PCM and I set up live data reporting and as Frag said the temp indicator is reading way high. Stat opened at 88 degree's and and fan kick in at 102 degree's. So my problem was butchered thermostat , faulty coolant temp sensor and looking like gauge and or temp sensor not working to spec. Might try and get a new temp sensor but not in a rush now as all working (except cab gauge lol)

I really appreciate all the advice and suggestion from you all so a big thank you to all the forum members who were so generous with there time and expertise.
Regards
David
PS if you want the make and model of my scanner just let me know