Temperature Sender Unit install

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mike
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Temperature Sender Unit install

Post by mike » Sun Oct 03, 2021 4:55 pm

Hi all - new 2.0l bongo owner here, coming up on our first issue. Our temp gauge was acting out yesterday - wasn't working, then it was back to normal reading, then back off etc. When I had a look around the engine I noticed the temp sender unit appeared to be pretty badly corroded, the flange ended up breaking off with hardly more than a wiggle of the wire :(

My questions are;
Does the coolant need to be drained to install the new unit?
Should the new one be installed to a specific torque setting?

I should say that I've been searching around for these answers for the better part of the morning but haven't found them. Many thanks
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g8dhe
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Re: Temperature Sender Unit install

Post by g8dhe » Sun Oct 03, 2021 5:19 pm

There are two sensors, one drives the display gauge alone and the other drives the ECU. If the display is acting up then obviously its that sensor that needs attention but you might be getting confused as they are in close proximity on the 2l!
18-510 (two wire sensor) is the ECU and 18-840C drives the display (single wire) see the mech parts diagram here http://www.lushprojects.com/bongopartsm ... mgno=.html

Normally for the coolant system and its sensors then torque settings are by hand its not under massive pressure in the system.
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Re: Temperature Sender Unit install

Post by rita » Mon Oct 04, 2021 12:12 am

g8dhe wrote: Sun Oct 03, 2021 5:19 pm There are two sensors, one drives the display gauge alone and the other drives the ECU. If the display is acting up then obviously its that sensor that needs attention but you might be getting confused as they are in close proximity on the 2l!
18-510 (two wire sensor) is the ECU and 18-840C drives the display (single wire) see the mech parts diagram here http://www.lushprojects.com/bongopartsm ... mgno=.html

Normally for the coolant system and its sensors then torque settings are by hand its not under massive pressure in the system.

??
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Re: Temperature Sender Unit install

Post by g8dhe » Mon Oct 04, 2021 8:53 am

Oops did I get them reversed ? Looks like it 18-510 is the single wire sensor for the display and the 18-840C is the two wire for the ECU!
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mike
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Re: Temperature Sender Unit install

Post by mike » Mon Oct 04, 2021 8:59 am

Thanks for the diagram, it's connected via a single green wire on mine.

Sorry for the repeated newb questions, is this something that I can install without needing to drain the coolant?
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Re: Temperature Sender Unit install

Post by g8dhe » Mon Oct 04, 2021 9:24 am

As your a 2l then whilst you will loose some coolant, provided you top up afterwards then the 2l will self bleed anyway, unlike the diesel or V6.
Just have the new sensor ready to go in when you unscrew the old, and you ought not to loose too much, especially if you leave the caps on the de-gassing tank in place!
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Re: Temperature Sender Unit install

Post by mike » Mon Oct 04, 2021 3:48 pm

Thanks, I really appreciate it!
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Re: Temperature Sender Unit install

Post by hawko » Sun Apr 24, 2022 1:49 pm

Hi there,

Full on newb with bongos and first post here :)

Just recently got a bongo 2.0L myself, and i think i have the same issue, I've seen the gauge move only once in the couple of weeks I've had it.

So sounds like hopefully just the same fix needed?
I had a look over the diagrams linked, but reading those is totally new to me too, and although i found the part on there with the provided part numbers, i couldn't work out where that actually would be in the engine bay. Any chance of a picture so i can see where it is i need to check?

Hope you can help,
Thanks!
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Re: Temperature Sender Unit install

Post by g8dhe » Sun Apr 24, 2022 2:06 pm

If you have only just bought it then there is always the question of "Is there a thermostat fitted ?" especially if you say it does move on occasions! Its a quite well known weeze to remove the thermostat to hide overheating problems :-(
If it was brought as a commercial deal then take it back straight away and ask them to check Thermostat/sensor.
If it was a private deal then you have no come back :-(
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Re: Temperature Sender Unit install

Post by hawko » Sun Apr 24, 2022 2:43 pm

Thanks a lot for the quick reply! :D

Ahh ok fair point, it was bought privately so no recourse there really, although the seller was a good guy and I'm still in contact if needed so. If theres one there, maybe it's just faulty potentially?

So where would i go looking to check first there is actually a thermostat fitted?

Then after that, the sensors discussed?

I need pointers on the locations in engine bay essentially to go check them, but i'd like to look all aspects over to check condition etc and then go from there i guess.

Cheers!
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Re: Temperature Sender Unit install

Post by g8dhe » Sun Apr 24, 2022 9:36 pm

In that case you will need to study the mech. Diagrams for your year and engine http://www.lushprojects.com/bongopartsmk2/
As a starter!
The thermostat is on the front of the engine, you will also obviously need to replace the coolant as it will be lost, the 2l is the easiest to drain and refill, as unlike the other engines it will self bleed any air left in the coolant system, however it still needs some care doing! The sensors are also mounted near the thermostat, one for the display the other for the ECU.
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hawko
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Re: Temperature Sender Unit install

Post by hawko » Wed Sep 14, 2022 10:19 pm

Well i got the parts for this and have only gotten so far with it, but i just wanted to check what the verdict would be in terms of MOT, would i need to get this all sorted and working for it to pass you think? Not sure if they check dash stuff so figured I'd just ask since its only a few months away :)

I did check taking the gauge to ground makes it move in the dash so i know that works atleast, and swapping the top sensor out didnt change things, so that wasnt at fault atleast. Just need to get the rest of the bits done when i have the time to really.
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Re: Temperature Sender Unit install

Post by TheLongRoad » Thu Sep 15, 2022 6:28 pm

The MOT doesn’t cover the temp gauge. They check warning lights go on and off as appropriate.
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