robt964

Does anybody know what thread size/pitch is used on these sensors?

Oil temp started over heating today. Completed all the usual debugging and appears to be that ridiculous PITA over completed CCU at fault. It starts the cooling fan when it should, but only allows it to run for about 2 seconds!

Anyway going to remove the CCU from the equation by fitting one of these if the thread permits.

https://www.merlinmotorsport.co.uk/s...fan-controller

Just need to know what the thread size is....

robt964

Ok, so I got off the sofa and pulled the sensor out. It's M14

Vandit

Where was the gauge indicating when said overheating happened? The car is setup to kick the fans on until it's like 9:30-10:00 and it's only for a couple of seconds as you describe, because it brings the temp down enough to disengage.

I did the resistor mod to bring down that engagement point to something I felt better about when sitting in traffic.

robt964

It was around there, yes. The fan only spins for about 2 secs, no way long enough to make any difference and the temperature continued to rise.

I don't mind eliminating the CCU from this task as I eventually want to be rid of it.

By reading a pelican thread it looks like the fan low speed kicks in at 100c/212f so there are two options to solve this.

Either a standard M14 100c-95c rad switch triggering a relay for the fan

Or

just use the adjustable M14 device here and have the ability to tweak the temp if necessary

robt964

Opted for the adjustable one. Will keep you all posted with how I get on

robt964

Thought I'd update this since I mentioned it on another thread.
I've had the part fitted for a few weeks now and very happy with it. You can precisely set exactly when you want the cooling fan to kick in, so I've set it a little lower than stock. I took the wheel arch liner out and drove the car about until hot. I then parked up letting the engine idle. When the needle reached a point that I'd like the fan to come on, I just leaned under the arch and set the adjuster with a small screwdriver so the fan kicked in.

No need for the dual speed resistor now as the fan is a simple on/off. I don't like messy visible wiring so I didn't use the supplied loom. Instead, I cut the loom about 10 inches from the sensor and fitted the male half of a waterproof 3-way Junior-power connector.

As the CCU would be relieved of its oil temp duties, the wires coming down to the temp sensor could be reused. These two wires together with a ground were soldered to the female half of the 3 way connector. The other end of these wires pop out at the connector on the body of the hvac just behind the fuse box. I disconnected them from here and fed them into the fuse box. The 2 or 3 wires which the CCU uses to drive/monitor the stock fan relay also come from this connector. They too must be removed.

Lastly, the 2 temp sender wires I'd just fed through to the fuse box were connected to the appropriate relay pins and a regular relay dropped in the slot to replace the stock dual action one. Job done and you'd never know to look at it

Happy to draw up a schematic if anybody fancies doing the same and needs it.

jstyer

I'll take a schematic!

robt964

Cool, I'll draw one up over xmas and post it here.

robt964

You can have a bit now This is the initial state of the wiring we'll alter.

(From Porsche 911 Carrera 2/4 Model 90 Sheet 3)

swftiii

Any pics of the install, I may be interested in this too as I have been unable to fix the automatic fan functionality.

Any other functions impacted from the CCU?

Thanks,
-Skip

Dick964

Hi Rob,

the link to the Amazon page shows an air vest.
Do you have a current pic or another link ?

I'm really intrested to do this update cause everything is working well but I feel the fan comes in to late.

Dick964

robt964

Here Partno EFCM14

Dick964

Ok ! Thanks Rob !

964George

Hey Rob
Did you ever get around to doing a step by step process?
Any pics?

9elevens

Hi,

Has anyone else done this modification? Can anyone comment on whether it works? The sensor looks much smaller in length will this affect oil flow?

Cheers