100c seen twice on the temp gauge

[teenmal]

There is not a problem fitting a Coolant sensor inside the engine,it can be achieve quite simply in many ways,as a lot of peeps have stated the Doctored gauge is useless ,this is one opertunity to fit the new sensor/sender into the useless gauge position.

I really dont want to start an argument regarding this as there may be some Commercial interest on the matter.

[mitchelln]

Apologies if my posts appear to be plugging certain products. I have absolutely no affinity at all with the manufacturer!

My suggestion was based on the OP already having a TM2 with the relay output capability and the possibilities that presented. Plus I do like a technical pimping challenge

[haydn callow]

Different type of sensor and electronics.

[g8dhe]

But the coolant temperature is not the temperature of the housing!
If you turn on the scavenger fan based on coolant temperature then it will be running whilst the vehicle is moving along with airflow directed over the engine housing itself by the undertray, rather than ONLY coming on when the housing temperature has risen too much.

[mitchelln]

On mine I'm not measuring coolant temperature. It's a thermistor sensor bolted to the block. That's how the TM2 and 4's work.
So it's measuring the block temperature

Located here on my 2L petrol:


Nice diagram by the way!

[Merlot man]

Thank you all for your inputs , it's what great about this forum
By reading through it it appears that the scavenger fan control is not as important as the coolant temps so , is there a better rad available then the standard Mazda item and if so where can I get one, also is it worth while to upgrade the rad fan to a stronger one when it comes on or maybe come on a little bit sooner ?
To keep things simple I'll probibly just fit an override switch on the scavenger as has been done by some in the past
Thanks in advance
Brian

[the1andonly]

There is not a problem fitting a Coolant sensor inside the engine,it can be achieve quite simply in many ways,as a lot of peeps have stated the Doctored gauge is useless ,this is one opertunity to fit the new sensor/sender into the useless gauge position.

made me think
I use DS18 temperature sensors all over the bongo, has anyone fitted one into "the useless gauge position" and how. what diameter / thread form?
where is this?
the cpu /fan temp sensor is on drivers side. another place to monitor.

[Katka]

I have a TM4 alarm fitted set at 101 degrees. Before this years trip and up some mountains I was worried about Bongo overheating and ran through all the possibilities to add cooling, including a more efficient radiator, extra fan to cool it, manual over-ride etc. I realised I was being paranoid and just put in a 40p resistor to activate the scav fan a bit earlier so my bottom didn't roast.
Before the trip had the coolant system checked to ensure no leaks and no air in the system. Happy to report the van coped with steep hill climbing in an air temp of 34 degrees. TM4 indicated high 90's and paranoia has passed - 'til next years planned Spanish trip anyway.
Japan gets really hot and really cold so I guess Bongo was designed for anything we're likely to throw at it so long as the cooling system is working as it should.

[mikeonb4c]

I have a TM4 alarm fitted set at 101 degrees. Before this years trip and up some mountains I was worried about Bongo overheating and ran through all the possibilities to add cooling, including a more efficient radiator, extra fan to cool it, manual over-ride etc. I realised I was being paranoid and just put in a 40p resistor to activate the scav fan a bit earlier so my bottom didn't roast.
Before the trip had the coolant system checked to ensure no leaks and no air in the system. Happy to report the van coped with steep hill climbing in an air temp of 34 degrees. TM4 indicated high 90's and paranoia has passed - 'til next years planned Spanish trip anyway.
Japan gets really hot and really cold so I guess Bongo was designed for anything we're likely to throw at it so long as the cooling system is working as it should.

Great post. I fitted an over-ride switch to my scavenger fan 11 years ago for very similar reasons: I didn't want the lump contributing to hot cab temperatures except when they might be welcome, and i reckoned engine ancillary equipment longevity wouldn't mind things being a bit cooler. Any contribution to helping engine cooling generally (heat soak reduction etc) was seen just as a happy side benefit, but no subsitute for a properly working cooling system. I've stuck with a manual system as having stuff to keep me engaged on long drives helps me stay awake/alert plus the human brain is a more interesting event manager than a fixed temp trigger switch. And also, intervention is not critical by Bongo design so that automation is not a must.