berg450

Well-Known Member
Hello
Anyone of you has any experience with an additionally built coolant level sensor? I have already red some posts about using sensor in the upper coolant pipe (where the bleed screw is) and also to build a sensor in the expansion tank.
Some people said that the sensor in the bleed screw is not the best way as it gives alarm signal when it is already late. My previus td5 had a sensor built in the expansion tank but I did not like it as it was only glued in and leaked under pressure.
I would like to install something as there are too many possibilities to have a leak somewhere and if I recognize it late then the engine is gone...but I do not want something which does not work on the proper way.
Ideas would be appreciated!
 
First question would be, what are you trying to measure?

1) coolant level?

2) coolant temperature while running?

Aftermarket gauges are readily available with senders that just need drilled and tapped into place somewhere that takes your fancy, you could even go so far as to use dual gauge pod and fit an oil pressure gauge too ;)

Not sure if the old RRC expansion tank cap fits a Td5? but they are still available for low coolant level senders.

https://www.ebay.co.uk/p/Durite-12-...Temperature-Gauge/2268562607?iid=121830037703

s-l1600 (2).jpg
 
Coolant level sensor in a TD5, many have used a BMW coolant tank , it is almost identical but has a sensor fitted., then you just need to decide how to fit a warnign lamp.

Cheers
 
Aftermarket gauges are readily available with senders that just need drilled and tapped into place somewhere that takes your fancy, you could even go so far as to use dual gauge pod and fit an oil pressure gauge too ;)
IMO if you want two gauges an EGT one would be more usefull than oil pressure, the easy way is to fit the probe in the EGR blanking plate which is not the best i know but it warns you if there is some management issue cos the injectors are compensating for each other so even if the 5'th's EGT goes higher it will be visible on the 1'st one too that's how i have them, a universal A pillar pod like this for RHD https://www.ebay.ie/itm/2-52mm-Pill...425718?hash=item41bae4b7f6:g:-FUAAOSwUKxYZnfZ needs just very little adjustment inside and at the bottom with angle grinder to fit well
my sensors.jpg

Gauges relocated.jpg
 
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First question would be, what are you trying to measure?

1) coolant level?

2) coolant temperature while running?

Aftermarket gauges are readily available with senders that just need drilled and tapped into place somewhere that takes your fancy, you could even go so far as to use dual gauge pod and fit an oil pressure gauge too ;)

Not sure if the old RRC expansion tank cap fits a Td5? but they are still available for low coolant level senders.

https://www.ebay.co.uk/p/Durite-12-...Temperature-Gauge/2268562607?iid=121830037703

View attachment 156236
I want to check coolant level. In case of a quick coolant loss it could be late when you recognise that the temp goes up (I think).
 
You can get small float sensors that push into a hole you drill and as you tighten the nut the rubber swells and seals.

I like the BMW tank suggestion.
 
1st update:
I have found a good quality sensor (local not from China), which, according to its spec, almost 100% sure that will do the job. I will get it within1-2 weeks and install.
I attach the application example just for your information. As you can see one of its application is to detect liquid in plastic bottle. If the thickness is less than 4mm the sensitivity can be set to detect only the liqued and give signal in case of low level.
XT218A1PAL2
upload_2018-9-12_14-18-9.png
 
Coolant level sensor in a TD5, many have used a BMW coolant tank , it is almost identical but has a sensor fitted., then you just need to decide how to fit a warnign lamp.
Cheers
Any suggestion on which coolant tank? Had a quick trawl on the xbay and couldnt see one that would fit current mounting and pipes - did I miss one?
 
New on the forum, out here in Oz we fit these devices to our vehicles : Engine SaverĀ® Try their website http://www.enginesaver.com.au/ and send an email if interested.
I'm not affiliated with them in any way, just use the product in my D2 having previously cooked my D1 due to split hose but no indication on the temp. gauge and large cloud of steam.
Hope this helps anyone interested
Bruce
 
New on the forum, out here in Oz we fit these devices to our vehicles : Engine SaverĀ® Try their website http://www.enginesaver.com.au/ and send an email if interested.
I'm not affiliated with them in any way, just use the product in my D2 having previously cooked my D1 due to split hose but no indication on the temp. gauge and large cloud of steam.
Hope this helps anyone interested
Bruce
In case of td5 the sensor is in the air bleed hole on the top hose, right? Is it checking temperature or detecting fluid on an other way?
In case of sudden coolant loss, while the engine is running and the pump is pumping coolant through the top pipe, is the top hose the right place the detect issue?
 
Not sure now, but iirc it may be the BMW E30 325i one. But no guarantees.

Cheers
That specific BMW expansion tank is from the 1990 325i.
For Thor V8 owners who are reading this, this tank won't work for your V8. That BMW tank doesn't have the connection port for the V8 heater plate hose.
 
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In case of sudden coolant loss, while the engine is running and the pump is pumping coolant through the top pipe, is the top hose the right place the detect issue?
Good question and IMO you are right, if the coolant drops while driving the tank will be empty way before the top hose gets empty... i say that a tank level sensor corroborated with coolant temp gauge is the best setup for that... the coolant temp gauge is the first on the list though cos if the coolant goes low the temp will start rising, for those who are claiming that the temp sensor must be in coolant to work i recommend a test as to blow on it with a hairdrier and watch the gauge.... so it will work in steam as well as in coolant or air, on those vehicles which are showing the real coolant level on the dash with linear gauges the gauge will drop for a very short time untill steam builds up but on the D2 which has a gauge in stages(at middle between 70 - 120*C) on a sudden coolant loss the temp of the air in the elbow will not drop below 70*C as to make the gauge to drop from the middle while in short time the steam's temp will be higher..... without any coolant level sensor last time when i lost coolant i saw that on the gauge cos the temp went above 105*C without any extra load or logical reason so i stopped and checked.
 
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Good question and IMO you are right, if the coolant drops while driving the tank will be empty way before the top hose gets empty... i say that a tank level sensor corroborated with coolant temp gauge is the best setup for that... the coolant temp gauge is the first on the list though cos if the coolant goes low the temp will start rising, for those who are claiming that the temp sensor must be in coolant to work i recommend a test as to blow on it with a hairdrier and watch the gauge.... so it will work in steam as well as in coolant or air, on those vehicles which are showing the real coolant level on the dash with linear gauges the gauge will drop for a very short time untill steam builds up but on the D2 which has a gauge in stages(at middle between 70 - 120*C) on a sudden coolant loss the temp of the air in the elbow will not drop below 70*C as to make the gauge to drop from the middle while in short time the steam's temp will be higher..... without any coolant level sensor last time when i lost coolant i saw that on the gauge cos the temp went above 105*C without any extra load or logical reason so i stopped and checked.
So the best way is to fit an additional temp sensor (not rely on the factory one) and a level sensor for the expansion tank.
 
That specific BMW expansion tank is from the 1990 325i.
It won't work if anyone has a V8 though. That tank doesn't have the connection port for the V8 heater plate hose.

I never said it did....or implied it did ;).......OP stated TD5 in his post and So did I in my reply.

Cheers
 
So the best way is to fit an additional temp sensor (not rely on the factory one) and a level sensor for the expansion tank.
That's the best in my opinion but it might not be in other's ... though the additional coolant temp gauge is the most important cos the factory gauge stays at the middle between 70 - 120*C
 

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