Topic: Fans cutting in late (Read 2836 times)

Webby the Bear · « **on:** 19 January 2020, 15:38:51 »

Afternoon guys

So car overheating issue was solved, i thought, by stat replacement.

Drove somewhere yesterday and temp kept creeping up. Temp only started coming down at just before the red zone. Driving was just town speeds.

Having owned my omega for years I know fan has always kicked in at about 95 on the gauge. So why is it now going near the red before cooling down?

STEMO · « **Reply #1 on:** 19 January 2020, 15:40:13 »

Quote from: Webby the Bear on 19 January 2020, 15:38:51

Afternoon guys

So car overheating issue was solved, i thought, by stat replacement.

Drove somewhere yesterday and temp kept creeping up. Temp only started coming down at just before the red zone. Driving was just town speeds.

Having owned my omega for years I know fan has always kicked in at about 95 on the gauge. So why is it now going near the red before cooling down?

Ermmmm....because it's an old, clapped out heap of rust? $:-\$

Webby the Bear · « **Reply #2 on:** 19 January 2020, 16:31:51 »

🤣🤣🤣 thanks for that Steve.

Any useful suggestions?

dave the builder · « **Reply #3 on:** 19 January 2020, 17:45:09 »

Can't rule out the brand new stat being faulty
I've had that before
replace a working stat with a new one ,because "maintenance"

to end up with problems

Doctor Gollum · « **Reply #4 on:** 19 January 2020, 18:00:03 »

Are the fans working correctly? Likewise the aircon...

Webby the Bear · « **Reply #5 on:** 19 January 2020, 19:30:54 »

Can’t see it being the stat. It’s exhibiting same symptoms as before stat change. And I also boiled it in the kettle before I fitted it and it opened no problem.

Air con doesn’t work. Something for the future. So I have it on eco. Next step testing fans? Is it any other setup than Ecu sends power to fans at given temp from temp sensor?

Doctor Gollum · « **Reply #6 on:** 19 January 2020, 19:56:39 »

The aircon system via relays and the two thermo switches on the rad. And the ecu from the ecu temp sender. Each can override the others.

Webby the Bear · « **Reply #7 on:** 19 January 2020, 21:23:36 »

Hmmm. So where to go from here?

dave the builder · « **Reply #8 on:** 19 January 2020, 21:30:59 »

there's a good guide on how to test the fans

Webby the Bear · « **Reply #9 on:** 20 January 2020, 08:31:27 »

thanks Dave. Is the issue not the fans being told to turn on or I’d overheat every time?

Doctor Gollum · « **Reply #10 on:** 20 January 2020, 08:35:49 »

Quote from: Webby the Bear on 20 January 2020, 08:31:27

thanks Dave. Is the issue not the fans being told to turn on or I’d overheat every time?

Perhaps, but you need to establish that they are actually running, hence the test... eg not running at slow speed will cause it to warm up before the ecu intervenes and throws them all on at Max

Webby the Bear · « **Reply #11 on:** 20 January 2020, 09:03:48 »

Ok I’ll have a look at the tests. Is there a thermoswitch for slow and full?

Webby the Bear · « **Reply #12 on:** 20 January 2020, 09:16:02 »

So looking at it there’s a test thing in the fuse box. I try grounding the pins that it tells you to and the fans will perform different speeds?

Doctor Gollum · « **Reply #13 on:** 20 January 2020, 09:40:44 »

Quote from: Webby the Bear on 20 January 2020, 09:16:02

So looking at it there’s a test thing in the fuse box. I try grounding the pins that it tells you to and the fans will perform different speeds?

Xactly... Or not if summat no worky

Nick W · « **Reply #14 on:** 20 January 2020, 09:56:23 »

Quote from: Webby the Bear on 20 January 2020, 09:16:02

So looking at it there’s a test thing in the fuse box. I try grounding the pins that it tells you to and the fans will perform different speeds?

start with the easy stuff:
Spin each fan by hand, and deal with any issues.
Disconnect the fans at the multiplug nearest to them, and feed each one 12v in turn.
Check the wiring and connectors to and at the fans/thermo switch/relays.
Check the relay works, either with a dedicated tester(a good use of a tenner) or by substitution.
Consider a new thermo switch. Testing them is fiddly and probably isn't worth the effort considering the cost.

Other things to consider:

Air locks
Water pump
Condition of the radiator

Webby the Bear · « **Reply #15 on:** 20 January 2020, 13:09:23 »

Nick spot on. Thanks boys

Webby the Bear · « **Reply #16 on:** 20 January 2020, 15:51:47 »

Ps is there more than one thermoswitch? I’m only seeing one on the rad...

Doctor Gollum · « **Reply #17 on:** 20 January 2020, 17:14:59 »

Should be two $:-\$

Left end of radiator looking down...

Top hose, thermo switch, thermo switch, drainplug.

Webby the Bear · « **Reply #18 on:** 20 January 2020, 19:53:57 »

Hmmm. I’ll look again tomorrow. Cheers boys 😘😘😘

Webby the Bear · « **Reply #19 on:** 21 January 2020, 17:58:56 »

As ever young DG you are bang on. 👍 I’ve got two on order. Been a nightmare getting hold of them. So the upper one is the fan switch. What’s the lower three-pin one for?

Doctor Gollum · « **Reply #20 on:** 21 January 2020, 19:50:00 »

Quote from: Webby the Bear on 21 January 2020, 17:58:56

As ever young DG you are bang on. 👍 I’ve got two on order. Been a nightmare getting hold of them. So the upper one is the fan switch. What’s the lower three-pin one for?

Switching the fans on

Upper is the cooler one, lower is the 'Oh shit we're about to melt' one

Webby the Bear · « **Reply #21 on:** 21 January 2020, 20:52:32 »

Ok thanks dg. Well they’re both getting replaced tomorrow. Cheap as chips. Fans all spin fine by hand.

News:

Author Topic: Fans cutting in late (Read 2836 times)

STEMO