D2-55B Temperature sender screw thread

[buttonfreebie]

Does anyone know the thread of the temperature sender. I only have the alarm panel without gauges and want to fit gauges and new dual senders. The oil sender I am fairly confident is 1/8 th NPT and think the temperature sender is 5/8th but not certain.

[PEA-JAY]

I installed a VDO water temperature 50mm instrument and it shares the existing water remprature alarm sender unit. Both work perfectly on my D2.55C
Raph.

[buttonfreebie]

My engine is the D2-55B and I suspect the sender only has an alarm contact. Can anyone confirm please
Graham

[Salty]

Your original temperature alarm sender should be in a pocket such that you can take it out of the pocket without losing any cooling water. Suggest you take it to your nearest motor factor store, and ask one of the assistants there if they can identify or just simply match it to a new sender unit that will work with your temperature gauge.
Even if it's not in a pocket, the amount of cooling water you'd lose is no big deal so long as you are not motoring anywhere, just top it up after the fitting has been replaced.

[geoff]

On my md22l I have installed a simple water flow sensor in the raw water line after the pump to warn of blockage or muppet me failing to turn on the water . Very cheap to buy [RS components ] and easy to fit . Geoff

[MarkTheBike]

Hi Geoff

That's a good idea, which one did you use? I've looked at the RS site and there's hundreds!

Cheers

[geoff]

Hi Mark, I will have a look on the site and try to let you know ,failing that I will be down at the boat on Thursday and will get the gen off the unit.  Geoff

[PEA-JAY]

Sorry, perhaps I wasn't clear. If installing a water temperature gauge You do not need a new water sender unit if you opt to install a VDO gauge. The existing sender unit will suffice.  All you have to do is to fit a second electric cable (I placed the joint inside the black box) and take it directly to the VDO gauge. I have tried this and it's been working for two seasons without fault. When you add an oil pressure gauge then yes you need to replace the sender unit with one that Has two contacts. The new sender unit and the gauge need to be calibrated identically, best scale is 0 - 5 bar. See images. I hope this helps!
Raph

[buttonfreebie]

Hi Raph
Thanks for further info and the photos.  I will check it out before buying a new temp sender. I plan to install the gauges as you have as I have the same panel arrangement  Did you use a hole saw for the Gauge cut outs
Graham

[PEA-JAY]

I did, but remember you're cutting into thin plastic, so it's risky. The heat might melt the panel and you will end up with a hole much larger than you wish! If you're unsure better go with chain holes and a file.

[geoff]

Mark , the unit is RS 257-082 .  it is shown on the site ,same as mine but twice the price ,still I bought mine about 15years ago. Geoff