Uploaded July 2017 | Updated September 2026, 1 week ago
How to fit a coolant level alarm to a car with a small shallow expansion tank like in this MG ZS. Same as the Rover 45 and probably lots of other cars. It would be easier to find a replacement later model tank that has the coolant level sensor built in, but as they are a bit expensive and not that common, I have gone down the route of fitting a level sensor to the existing tank.
It is tricky finding the right size sensor. Here is a link for the one I used:
From amazon UK: amzn.to/2sTSM31
Or on amazon USA: amzn.to/2tPKLAM
As you will see in the video I cut it down by 16mm so that it didn't touch the bonnet(hood). That would be slightly easier doing it before fitting it to the tank. It was quite easy with a small disk cutter. Cut 2 slots down the sides and one around the shaft 16mm from the top and then split it apart with a screwdriver and they break away.
In this example we use an led to indicate low water. Plenty on Amazon again:
Amazon UK: amzn.to/2tTuwCr
Amazon USA: amzn.to/2tZ1DFN
Also see my other video on fitting a water level alarm to a LANDROVER Freelander1: youtu.be/IQXcK0nf_MU
We use the same circuit introduced in that video for this project. Except we modify it to give a longer filtering time by increasing the capacitor to 10,000uF. That can be a 10v sort if the LED indicator is used. It would have to be 16v or more if a beeper is used. The circuit shown filters out signals from the sensor due to the water sloshing around the tank. It does a similar job to what the ECU does on the later model cars that include the water sensor as standard. i.e. The alarm wont come on until the sensor is giving a consistently low indication for 30 seconds or more.
Here a buying link for the 10,000uF capacitor from:
Amazon UK: amzn.to/2sOizyB
Amazon USA: amzn.to/2uRrNqn
For the buying links for the other components see the description in the above mentioned video of mine about the freelander1 alarm.
For the rubber washers mentioned here's buying links:
Amazon uk: amzn.to/2tTBpUb
Amazon usa: amzn.to/2tPt9VK
Stainless steel M10 washers:
Amazon UK: amzn.to/2sU56QL
Amazon usa: amzn.to/2sNsoN4
Now maybe I was unlucky but that sensor of mine had a small pin hole leak. I fixed it with 2k paint, which sets like a resin. Use gloves with that stuff and dont breath the fumes and read about safety precautions. The detail of the fix is shown at the end of the video in an appendix.
Subscribe to the channel for similar DIY, fixing stuff, car bits and tech reviews here:
youtube.com/subscribe_widget?p=comeinhandynow
Note, if you want to be notified of new videos click on the bell symbol on my home page.
See other videos on my channel here:
youtube.com/user/comeinhandynow
If anyone wants to show appreciation for any money savings, or just help support the channel and future videos then you now can. Use this link: paypal.me/comeinhandy
OR you can support me by using the Amazon and Ebay links to buy other stuff that you would usually buy, it will not cost you anything more, but will help this channel. e.g. Generally useful stuff:
Face mask:
Amazon UK: amzn.to/2GHE9d6
Similar ones on Amazon USA: amzn.to/2IHmip1
Eye goggles: Amazon UK: amzn.to/2IUSqos
Amazon USA: amzn.to/2GAtIXJ
Rubber disposible gloves are also useful, here's the links for
eBay USA: ebay.us/GGqmTJ
eBay UK: ebay.us/cE1BHK
Amazon UK: amzn.to/3aikbl8
Amazon USA: amzn.to/3cdwjpD
Amazon Canada: amzn.to/2Q0VHZm
Amazon Australia: amzn.to/2QlUawX
A set of precision screwdrivers:
Amazon UK: amzn.to/2W311si
Amazon USA: amzn.to/2Z322T5
Torx bits sets:
Amazon UK: amzn.to/2Pgmf48
Or Amazon USA: amzn.to/2XlOK3h
I’m on Facebook here: facebook.com/comeinhandynow
Become a Patron to get extra content or previews or sponsor here: patreon.com/user?u=31365629&fan_landing=true
The video is about my personal opinion and experience and contains no paid for product placements. No responsibility is accepted for any perceived recommendation for or against a product or feature nor any consequential damage or harm since this video is just my personal experience. You accept by watching this video that you accept any responsibility for any subsequent actions or decisions that you take.
Note on copyright / licensing: This video was created using Apple iMovie and as such any music or video content is fully licensed by their terms and conditions for free publication and distribution. See the Apple iMovie software license agreement. Additional background music free used royalty and copyright free (no copyright songs) from the following source:
AndyM -Oasis [Faded NCS Release] youtube.com/watch?v=1C-EjJHn6SY
How to fit a coolant level alarm to a car with a small shallow expansion tank like in this MG ZS. Same as the Rover 45 and probably lots of other cars. It would be easier to find a replacement later model tank that has the coolant level sensor built in, but as they are a bit expensive and not that common, I have gone down the route of fitting a level sensor to the existing tank.
It is tricky finding the right size sensor. Here is a link for the one I used:
From amazon UK: amzn.to/2sTSM31
Or on amazon USA: amzn.to/2tPKLAM
As you will see in the video I cut it down by 16mm so that it didn't touch the bonnet(hood). That would be slightly easier doing it before fitting it to the tank. It was quite easy with a small disk cutter. Cut 2 slots down the sides and one around the shaft 16mm from the top and then split it apart with a screwdriver and they break away.
In this example we use an led to indicate low water. Plenty on Amazon again:
Amazon UK: amzn.to/2tTuwCr
Amazon USA: amzn.to/2tZ1DFN
Also see my other video on fitting a water level alarm to a LANDROVER Freelander1: youtu.be/IQXcK0nf_MU
We use the same circuit introduced in that video for this project. Except we modify it to give a longer filtering time by increasing the capacitor to 10,000uF. That can be a 10v sort if the LED indicator is used. It would have to be 16v or more if a beeper is used. The circuit shown filters out signals from the sensor due to the water sloshing around the tank. It does a similar job to what the ECU does on the later model cars that include the water sensor as standard. i.e. The alarm wont come on until the sensor is giving a consistently low indication for 30 seconds or more.
Here a buying link for the 10,000uF capacitor from:
Amazon UK: amzn.to/2sOizyB
Amazon USA: amzn.to/2uRrNqn
For the buying links for the other components see the description in the above mentioned video of mine about the freelander1 alarm.
For the rubber washers mentioned here's buying links:
Amazon uk: amzn.to/2tTBpUb
Amazon usa: amzn.to/2tPt9VK
Stainless steel M10 washers:
Amazon UK: amzn.to/2sU56QL
Amazon usa: amzn.to/2sNsoN4
Now maybe I was unlucky but that sensor of mine had a small pin hole leak. I fixed it with 2k paint, which sets like a resin. Use gloves with that stuff and dont breath the fumes and read about safety precautions. The detail of the fix is shown at the end of the video in an appendix.
Subscribe to the channel for similar DIY, fixing stuff, car bits and tech reviews here:
youtube.com/subscribe_widget?p=comeinhandynow
Note, if you want to be notified of new videos click on the bell symbol on my home page.
See other videos on my channel here:
youtube.com/user/comeinhandynow
If anyone wants to show appreciation for any money savings, or just help support the channel and future videos then you now can. Use this link: paypal.me/comeinhandy
OR you can support me by using the Amazon and Ebay links to buy other stuff that you would usually buy, it will not cost you anything more, but will help this channel. e.g. Generally useful stuff:
Face mask:
Amazon UK: amzn.to/2GHE9d6
Similar ones on Amazon USA: amzn.to/2IHmip1
Eye goggles: Amazon UK: amzn.to/2IUSqos
Amazon USA: amzn.to/2GAtIXJ
Rubber disposible gloves are also useful, here's the links for
eBay USA: ebay.us/GGqmTJ
eBay UK: ebay.us/cE1BHK
Amazon UK: amzn.to/3aikbl8
Amazon USA: amzn.to/3cdwjpD
Amazon Canada: amzn.to/2Q0VHZm
Amazon Australia: amzn.to/2QlUawX
A set of precision screwdrivers:
Amazon UK: amzn.to/2W311si
Amazon USA: amzn.to/2Z322T5
Torx bits sets:
Amazon UK: amzn.to/2Pgmf48
Or Amazon USA: amzn.to/2XlOK3h
I’m on Facebook here: facebook.com/comeinhandynow
Become a Patron to get extra content or previews or sponsor here: patreon.com/user?u=31365629&fan_landing=true
The video is about my personal opinion and experience and contains no paid for product placements. No responsibility is accepted for any perceived recommendation for or against a product or feature nor any consequential damage or harm since this video is just my personal experience. You accept by watching this video that you accept any responsibility for any subsequent actions or decisions that you take.
Note on copyright / licensing: This video was created using Apple iMovie and as such any music or video content is fully licensed by their terms and conditions for free publication and distribution. See the Apple iMovie software license agreement. Additional background music free used royalty and copyright free (no copyright songs) from the following source:
AndyM -Oasis [Faded NCS Release] youtube.com/watch?v=1C-EjJHn6SY
