Fitting TM4 and Coolant Alarm to 2L petrol

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mitchelln
Bongolier
Posts: 188
Joined: Wed Jun 21, 2017 12:39 pm
Location: Dorset

Fitting TM4 and Coolant Alarm to 2L petrol

Post by mitchelln » Sun Aug 06, 2017 11:20 am

I've got the TM4 engine monitor and coolant alarm fitted to my 2L petrol.

All pretty straight forward. Scary part was drilling into the header tank to fit the screw "sensor". Got wetter than expected ;) I waited a few weeks after changing the coolant as I'd read on this forum that you get false alarms if you fit it with brand new red coolant.

The only other challenge was finding somewhere on the engine to fit the TM4's temperature thermistor. Lot's of knowledge out there for the diesel, not so for the petrol!

Here are some pics:

Header tank screw. The wire is fed back into the cab via the existing wiring seal behind the header tank.
Image

TM4 temperature sensor mounted on the engine. The wire feeds back via the existing wiring loom grommet on drivers side:
Image

Module in place in the large cubby in front of the gear shifter. This still leaves plenty of room in the cubby for storage. I had to (carefully) drill a hole for the wire and used a rubber gasket. Oops, pencil centre mark still there ;)
Image

The engine temperature read out seems accurate. Typically shows 88-90 when running, which is the thermostat operating temp (handy for spotting if it sticks again!). Fan kicks in precisely at 92 degrees. Never see it go above 94 so far, even in standstill traffic. Alarm threshold is set to 100 degrees.
I like the way it automatically lights up in low light with a nice gentle glow.

The only thing that is a little annoying is the coolant alarm part goes off very loudly for about 4 seconds every time I start the engine. It peters out with a plaintive squeal and stops. Is this normal?

It's also very loud. I might open it up and insert a resistor on the buzzer to drop the volume a bit.

Hope 2L owners find this useful.
Last edited by mitchelln on Sun Aug 06, 2017 11:46 am, edited 5 times in total.
Black Aero City Runner 2L petrol with full side conversion
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g8dhe
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Re: Fitting TM4 and Coolant Alarm to 2L petrol

Post by g8dhe » Sun Aug 06, 2017 11:32 am

The alarm at switch on is the self-test I believe!
Geoff
2001 Aero V6, AFT, full side conversion.
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mitchelln
Bongolier
Posts: 188
Joined: Wed Jun 21, 2017 12:39 pm
Location: Dorset

Re: Fitting TM4 and Coolant Alarm to 2L petrol

Post by mitchelln » Sun Aug 06, 2017 11:38 am

Okay. Thanks for that. Glad it's normal behaviour!

It'll be fine once I drop the volume a bit :)

I feel much happier now I'm fully protected from cooling issues going unnoticed until it becomes serious.
Black Aero City Runner 2L petrol with full side conversion
mitchelln
Bongolier
Posts: 188
Joined: Wed Jun 21, 2017 12:39 pm
Location: Dorset

Re: Fitting TM4 and Coolant Alarm to 2L petrol

Post by mitchelln » Sun Aug 06, 2017 12:38 pm

Forget to say, the module is powered via a piggy back fuse holder. Those things are a godsend :)
Black Aero City Runner 2L petrol with full side conversion
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