Mark the external thread using a marker pen so you can get the orientation correct as you tighten the nut

Fitted the range rover float switch to my 300tdi defender just a pointer for anyone fitting 1 of these, on the dash warning lights there is an unused transmission temperature warning light (looks like a cog with a thermometer in the middle) this will give you a nice stock finish inside the car would recommend this mod to everyone its so easy

Super idea. I check my level on a regular basis but this is worth doing in case of a sudden leak developing.

5:58 - "Is someone stealing your Defender?" - "No, no, just a coolant leak!"

It’s getting like Blue Peter on here just lately,I’ll order some sticky back plastic and get Jackie to save the tube out of the toilet rolls and the egg boxes for your next video .

Keeping it simple as always Mike! Another video to save.👍👍👍👍

What a brilliant idea 👍

What a great idea! So simple - making Land Rovers better!

My 90 turbo diesel had the sensor cap fitted, and a plain red indicator popped through the dash when it had a defender 200tdi dropped in as part of some sort of upgrade programme in the mid 1990s via LR. Great idea to use off the shelf bits, I'll be fitting similar to my other vehicles I'm sure, thanks!

Just doing this to my 90 thanks for the idea fitted a buzzer led to dash

Mike, on my 300Tdi I have fitted the same switch exactly as you showed with the exception that mine has a "self check" that the alarm is functioning, it has a relay in the circuit that earths through the oil pressure switch when the ignition is first turned on, this activates the alarm until oil pressure is established, I have a buzzer audible alarm plus a large orange light in dash centre between oil pressure and capillary type temperature gauge. Once the engine is running, if the alarm sounds, it means either oil pressure failure or loss of coolant. It has worked well for many years.

To make sure the switch is dead upright put a marker pen on the threads to ensure it doesnt spin when tightening. Great idea!

Thank you sincerely. Definitely getting that.

Thanks so much for this video Mike. I have been looking for something like this switch for ages, I always keep a look-out at all my gauges in particular when I'm on the motorway but it only takes a few minutes for an ally head to get damaged. The old Bedford TK's had a sensor on the header tank but they are not around in scrapyards these day's to get one off. So !! now I know what my next job is, and it can be done during the winter and it is so cheap and simple,,,, perfect. Once again , many thanks from Yorkshire Rob. Please keep these video's coming .

Super idea! Top marks!

Great idea just saved me from getting on of the kits that cost loads

Another great Top Tip, Mike. Thanks a bunch. I have those kind of switches at work on a plate developer and I might give it a go. Edit: There are also versions that work vertically, though it might be a little more finnicky to get the right height.

Super video Mike ,thanks

On AliExpress you can get the floating sensor/switch for less than $1 and an LED with buzzer for same. That's a less than $2 solution. Wow. I've been looking for an affordable coolant level alarm and now I have it. Add another that is turned the other way round as you had done before and it will function for "too much coolant" or whatever use case fits.

did mine works brilliant great idea

Hi. I think it is a great idea. Definitely I'll do one for my S3. Once I've installed one on a gasoline tank on a boat. a marine dedicated kit with a gauge and the float, (can be connected to a fuel gauge or a water one). Here in Sweden cost about 65 us dollars. Thanks for the great tip and the great vids.

We use exact same switch in the water tanks on roadsweepers stops the water pumps running dry👍

Nice and simple - but clever idea!

Thanks! Great idea!

Genius. What a good idea.

Brilliant information

Great idea Mike 👍👍👍👍

Excellent report squadron leader..top of the pops .. and we all do like a nice clinch ..😎😁pip pips

Your a bloody genius, keep them coming, great!

I did that as well since ghe range rover one is not good for 24v but i used a stainless one :)

I got one of this attached on the outside of the coolant tank and a small buzzer. CQRobot Non-Contact Water/Liquid Level Sensor, pretty cool device.

I just installed one of these on my Range Rover Classic. The "special" electronic cap on the overflow tank had failed. On the classic, the float needs to "drop" (flipped the other way around, like you had it in your first attempt apparently. When installed correctly, in the Classic, the switch needs to be closed when the coolant level is correct. The light on the dash comes on when the circuit is broken, coolant level drops) in order to work with the existing wiring in the Classic. It was still very straight forward. Drilled the hole in the expansion tank, popped in the float switch, put some connectors on the ends of the float switch, and plugged it right into where the overflow tank cap connectors went. Your videos are great and amazingly helpful!! Keep them coming.

Brilliant

Quality 👍

Great video and great and simple solution for a problem that can become a big mess. Not long ago a silicon end cap broke on my Disco TD5 and I detected the fail from the inside of the car because of the coolant smell. Anyway, the circuit was almost empty and I really don't know how did I manage not to blow the gasket!! Thank you Mike!!

On the 200TDi defender main loom (bulkhead) there is a slate/red wire on the main connector that hooks up to the chassis loom ( it has no connection on it) . This would normally be used for the gear box temp switch, as it's not used an pretty much all defenders it would be a good warning light to hook it up to on the dash

That's a good idea my 1994 Peugeot 405 TD has a level switch built into the radiator which has come in very use full for cracked plastic water housing's on the engine!

Great little stitch in time Mike. By the time most people realise their engine is overheating, the head gasket has already been damaged. Good video. Enjoyed it.

Great videos!! 👌

A great gadget, Mike! I appreciate. But I know these kind of float switches are designed to put them in from the outside. You actually don't need to pull it with the wires from the inside. ;-)

Excellent

Hi there great video and very interesting I would like to say though that plastic tanks split regularly so even with the alarm you still will be stranded.. go with the aluminium tank and range rover cap that way you will be covering both angles.. great video and carry on making them 4x4 overland John Desert specialist

Perfect timing! I’ve been looking at doing something like this for a while. Thanks Mike. Just a quick note to UK viewers, Amazon have these in black but they show two types, one with the top hat style washer and one with a conventional washer.

Great to see good old British shed engineering

Excellent tip about the float switch. If only I had one before the block, rear core plug failed. New head now. I installed a Muirhead coolant level module. Fitted two stainless steel bolts with large washers and neoprene rubber washers (probes), either side of that cross piece in the tank. The module sends an AC signal between the two probes. Light on dash and a small buzzer. The neat thing is it does a self test when the ignition is turned on, ie., light and buzzers. No wounder the tanks fail at the seam because they balloon up under pressure and the heat/cold cycles. Nice demo. Remarkable glue between the two halves of the tank.

Just last night reading about a chap I no cooling problems long way from home, Romainia took 7 weeks to deliver his 110 back to UK! That simple idea would of solved that ,brilliant.

I fitted the Range Rover expansion cap with the float switch to my D1, there’s a low coolant alarm kit on eBay which I have found to work really well. The other thing I have is the Fourby 4x4 clock, this is set up to give me coolant temperature via a probe in the top of the cylinder head. That way I can accurately monitor water temperature and I know if the level is low 👍🏻

Awesome! Patent pending? Lol. Thanks for the time expended. 👍🏻🙏🏽🙏🏽😷😷🦘🦘

Great idea and video Mike, just a warning to others I see yours is rated upto 150°c, which is good, similar cheaper ones on ebay I looked at were only rated to 60°c which is not, if anyone is thinking of buying one.

Hi Mike, I had the same set up on my 300Tdi and I found that the switch would "perish" every 5 years or so, so I carried a spare in the cubby. I've since gone to the RRC Cap with a double throw relay to make the buzzer work simply. Just some advice on fitting the float switch, put it to the front of the tank instead of the back, that way your alarm won't sound under heavy braking or when going down very steep hills.

Escort mk3 used to have them in the engine coolant bottles and a logon the dash if the water went below the level

Same principle used in commercial buildings on water tanks for high / low warning levels 👍

Super idea! Im actualy driving td5 but will build series 3 with 300tdi engine.

Hi Mike 🤔 great idea 🤔upside down 😂 will work in Australia 😁😁😁 only kidding 😁 well it' is happy Thursday 🍺🍺🍺🍷🍷🍷 keep safe and say well 👍 oh and it's snowing ❄️ over here 👍👍👍🇬🇧🇬🇧🇬🇧

Cheap and easy way to avoid heartbreak mike !

Just ordered mine Mike! 2€ from ebay. Just las week I had a problem with the waterpump belt, the temperature raised ... and the level went down. Thanks for sharing all your knowledge👍

As a RRC owner for many years I feel quite smug, it saved my old VM a few times and now I have a 300 tdi which as you said Mike can have low coolant problems I have left it on, the original switch does fall apart sometimes so when it does and it will I will replace it with one like yours.

In the UK these level switches are used on IMI / Baxi Potterton Powermax boilers. They should be ok to use up to approx 4 bar pressure and around 140°C. They are obtainable via eBay, although they can be expensive over here.

An extra tank just for jamesons? They could also be used as wading sensors hooked up to leds on a defender diagram plate fixed to the dashboard:)

Hi Mike the switches only cost £3.45 on ebay UK and they come in black

That’s such a good idea! I’m going to do this on my td5, although the tank is rounded. Would have saved me a head gasket!

Even cheaper on ebay got two for £6.......You are a star my man and like the comment below on my td5 would have saved me a cylinder head.

Great video as usual..I’ve been a sub for some time now and really enjoy your channel. I’ve a 2003 disco 2. V 8 4.6L Bosch petrol . SE 7. 96k. No I’ve had it 10 years but only use it in Portugal every summer, when the weather is around 27-30 degrees. I’ve been listening to your advice about overheating and head gasket repairs as well as all the other blogs about it. Some advise I should replace the thermostat to the TD 5 stat because it allows more coolant through, other Recommend fitting a Cumputer to the ecu to monitor heating. My question is , What is your advise on preventing overheating?. Ie what should I fit. Your opinion would be greatly appreciated. Keep up the great videos. P.

I know I'm late to the party, but I'd like to suggest an improvement to your circuit. Reversing the polarity to the switch would be safer, if there's a short circuit the warning would activate rather than blow the fuse (which may not be discovered), rendering the system useless. Keep up the good work!

This is one of those simple ideas that everybody slaps their foreheads when told and wonder 'why i didn't think of that!' Like you i would have installed the switch N/C with the float falling with the coolant level... The annoying thing is i've used these for the same reason on other machines at work in the past, and in EVERY case had to use relay as i installed them all the 'wrong' way!

Added to my Amazon wish list. On my P38 I added an aluminum adapter to the lower radiator hose which has a port for a temperature sensor. I bought an Autometer temperature gauge and sensor. Wired it all up and mounted the gauge on the dash to the left of the steering wheel where it is easily visible. Now I know my normal running temperature, 180 degrees F. Going up by 10 degrees doesn't even register on the dash gauge.

Fantastic!!! Would you be able to do a full install in a vehicle to be able to see how to properly do the wiring?

Believe me or not, but that's exactly what I did a year ago, just after my cylinder head broke because of the loss of coolant. Funny that with the same type of switch, mounted just a little bit lower in the tank. So look's familiar :) But the only problem is that the buzzer I've attached scares me sometimes. It does't activate while crossing any bumps, but it does while driving around a tight curve left, because all coolant has enough time to move to the right. I've got used to this sound, especially that it confirms that the system still works. But I have the Idea to attach inside the tank some flexible plastic wall to slow down the movement of my coolant. But I'm just too lazy to do it :)

The only problem is when the water level gets a little low the motion of the vehicle will cause a pulsing alarm as the float bounces up and down with the motion of the vehicle, you could incorporate a relay that that latches on when activated giving a permanent power supply to a warning neon, you would need a reset button to break the latch after topping the water up or wire it so turning the engine off kills the power breaking the latch; both would work. Other than that a good idea.

That's good warning can you fit in series to your low brake fluid warning Mike

Great if you live in Holland on the flats.... going to be going on and off if you live in the hills. 😁 So think a light rather than a alarm would be better. Great idea though. 👍

Love your videos Mike. But this one made me need the bathroom.

Hi Mike, Thanks for the video, great idea! Do you think this switch would fit in the 19j metal style expansion tank as well?

“It’s all mucky now, cos I’ve had it in and out that many times “ Ooer ,missus

I've fitted mine but have noticed its rated to 60c i have sourced a stainless one that is a direct replacement if it fails

I always enjoy your videos and as a newbie to Land Rover and Defenders in particular, I’ll check if my 2011 have such a warning device. If not I’ll implement your great idea. I do have a comment and a suggestion. Not knowing the difference in diameter, would it not be ok to make the hole slightly bigger to allow fitting the switch from the outside ? The silicone seal and collar seem to be the same diameter. Suggestion. Mark the threaded part with the correct switch position up. Either by marker pen or a notch.

Watched 1/2 doz of videos. Like your common sense & keeping it simple! I've been looking for Defender 110's, 1988, 1992; 200TDI imported from England, no emissions. Any red flags to watch for? Watching from Payson,Utah.

I bought a transparent coolant tank for my Discovery 1 so you can always see the level.

There's a nice quality float switch available from Devilsown water methanol products, self sealing and a lot easier to fit.

Great solution. If you are really paranoid you could simply loop the wire of your fuel solenoid via this switch. :-)

Also doubles up as a burglar alarm just in case anyone tries breaking in to your through the coolant system 🤣

thanks for the info on the alarm have you got a part number for that , many thanks

Hi Mike any ideas how you could make the same system work for a td5 that has a round header tank? I still hope you do a td5 to strip and rebuild like you once mentioned. Td5s are getting to the age were the owners repair them themselves and I think you would get alot of views with the amount of people online who are scared of touching them because they have a few crude sensors and an ECU.

I got one of these and I found you put the seal on wrong the seal goes on the inside as you can have the seal not quite sit right the fat lip seals the senser to the tank keeping the threads dry the way you installed it the threads can get wet and although the outside is seal the threads are not allowing it to leak out the threads installed right the pressure will push the senser into the seal keeping it sealed at higher pressures not that it will ever be under much pressure And you can buy them in black which looks a but nicer on the black tanks or black mettle tanks

Good idea Even if your alarm is a little bit surprising when you are on the road like where are the cops ? May be a flashing led ? I have the LR system but i Had recently to change the plug cause of the valve broken. The pb i have is that i swaped the engine 300 tdi by myself and then dont know if my coolant tank is at the good altitude and so don t know if the cross inside indicate the good level Whatever good video good subject very useful i think 👍

these float switches are on ebay uk in black £5-6 but check the spec's not all are rated for engine temp's,

Good example of KISS technology. However with the discussion of quality parts in mind , I suggest to go for at quality part . Also keep in mind that some switches are for Un-pressurised application , if 15PSI is regarded pressurised , I really don't know . It is a good idear , just be sure it is reliable , otherwise it can end up as another indicator light " now it works, Now it don't" and boom here goes your head. I will install a cheap one in my sprinkler , it is also annoying to run out of window washer , but hardly as mission critical.

Hi Mike, thanks for the great videos...you and the trailfitters toolbox made life with my 1st Defender a little easier...it was a steep learning curve but I have been bitten by the dirty LR bug 🤣 Can I ask what’s involved in exporting to Canada... I have a very original 200tdi 110 CSW that I am thinking of selling and am wondering if I would make more selling it for export?...

Great idea and a lot cheaper than the RR part. My only concern is you did not tilt it forward simulating a steep decent, might be an issue as the switch is at the back!

nowadays you have to have it trigger a text message to their cell phone so they can respond more immediate lol!

Brilliant, how about a ballcock sett up like in a bog and a spare header tank, instant top up 🤣🤣🤣

great research....do we know if the switch will work ok with 90deg water and antifreeze?

Hi Mike do you recommend changing the door hinges and mirror arms to stainless steel to prevent rusting in those areas?

What sort of angle (Fwd//Back) does it take for the alarm to go off? That is if u are going down a very steep hill will the float switch activate because the fluid has rushed to the front of the reservoir....

Hi Mike, brilliant as ever. Does this give you any false alarms while going uphill or going to a curve?

Hello, I Have a P38 1998 4.0 V8 GEMS. The Air-Con Pump has a Noisey Front Bearing, are They Simple Enough to Change the Bearing Please ? The System I Think is Already De-Gas'd on it's own. THANK YOU.

Would it seal properly on the TD4's spherical expansion tanks?

Hi Mike, could you do a video on the 19j type wheel bearings the ones where the axle oil lubricates the bearings? Cheers buddy

Any recommendations for a float switch like this that would survive engine coolant?

Mike, if the tank is half full when cold, how much does the level drop normally @ standard operating temp.