Fitting Charge Pressure Guage kit to KAD42

the temp sensor will almost certainly be a negative temperature coefficient thermistor (NTC). Very cheap, easy to get hold off. Just a question of finding an equivalent. They are not polarity sensitive either.
 
kashurst said:
the temp sensor will almost certainly be a negative temperature coefficient thermistor (NTC). Very cheap, easy to get hold off. Just a question of finding an equivalent. They are not polarity sensitive either.
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Well....we’ve found our expert then :encouragement:

Great! I’ll see what I can find out from ThermoPro.
 
I installed Farsco's genius setup for boost pressure guages, and got the boat out today to test them. They worked perfectly, and the signal to the display on the flybridge was fine toi. Much kudos!
 
markc said:
I installed Farsco's genius setup for boost pressure guages, and got the boat out today to test them. They worked perfectly, and the signal to the display on the flybridge was fine toi. Much kudos!
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Awesome! Glad it worked....now for bbq meat kit as water temp sensors :):):)

Forgot to add....where the readings what you expected?
 
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kashurst said:
just ordered the BBQ thermometer - I will report back when I have figured out the sensors
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ThermoPro are asking their engineers for the probe specs.

They think it’s a NTC 100k ohms at +25C b=3950 and will confirm.

Means naff all to me but they have been very helpful. I think they are interested in what the crazy brits are doing :)
 
I have tested the probes that came with the thermometer today and I agree with them - can't confirm the b value but thats a very popular choice.
just ordered 5 equivalents from amazon, (£1 each including 1m leads) very popular on 3D printers apparently.
 
OK new thermistors arrived today - 100K ohm NTC with a b value of 3950 , pre soldered to 1m of tinned wire with a very nice heat shrink job done. And they were on Prime free delivery too.
https://www.amazon.co.uk/gp/product/B06Y624LZQ/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
The actual thermistor is a tiny glass bead @ 2mm in diameter so will need protecting. I will be chopping up the original stainless probes to make a protective cover and epoxying the sensors inside. However any electrically equivalent 100Kohm b = 3950, NTC should work fine as long as it is suitably protected. As I am only after indication of temperature on the engines rather than absolute accuracy, I will be attaching the sensor to the rubber hose that comes out of the top of the thermostat housing with self amalgamating tape. (spared no expense - this is a quality job after all!) In this way the electronics are not electrically connected to the engine at all so no galvanic issues and being a lazy sod, I don't have to go to the trouble of machining up a new blank plug to screw into the thermostat housing either or risk spilling any of the recently replaced, precious volvo antifreeze mix. (and if it all self destructs after a few hours well never mind)

I bought the UMI thermometer kit as it only shows the two temperatures, so I hopefully won't have to explain the pork, or beef settings (and of course the display is backlight in red to preserve night vision ;-) there must be a boaty design engineer at UMI) I will use the LCD display as Food = Port, Barbecue = Starboard, pretty obvious really.
https://www.amazon.co.uk/gp/product/B014DAVHSQ/ref=ppx_yo_dt_b_asin_title_o02_s00?ie=UTF8&psc=1

I tested the temperature readings with the new sensors and the original probes and from 18 to 100 degs C they read exactly the same as the original probe style sensors. Can't test it on the boat until the summer so as a basic EMC electrical interference test, I put the sensor and base unit in the engine bay of a car (running engine) with the sensor wires draped over the spark plug leads and fuel injector cables. Didn't seem to bother it at all
I think that was 15 minutes of arduous product development well spent so it should now be perfect, duck taped onto a KAMD 300 in an atlantic storm. :-)
 
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Sounds ace!

Glad you’ve got a setup you’re happy with.

My only thought is you are reading the external rubber hose temp rather than the coolant temp. Will it give you any real warning fast enough?
 
pretty sure it will respond fast enough. The specific heat capacity of water is about 4 times greater than rubber. So if the cooling water is heating up, the rubber will heat up just as fast. The rubber is @ 3mm thick so the surface temp will be slightly less than the internal temp. However if I wrap the sensor onto the rubber hose with amalgamating tape, the sensor is effectively submerged into the rubber hose, and not exposed to the ambient air cooling it down. Should be good enough and plenty fast enough to indicate a developing issue. And I still have the over temp sensor/alarm indicators and I know they work. (2 new impellers please!)
 
kashurst said:
pretty sure it will respond fast enough. The specific heat capacity of water is about 4 times greater than rubber. So if the cooling water is heating up, the rubber will heat up just as fast. The rubber is @ 3mm thick so the surface temp will be slightly less than the internal temp. However if I wrap the sensor onto the rubber hose with amalgamating tape, the sensor is effectively submerged into the rubber hose, and not exposed to the ambient air cooling it down. Should be good enough and plenty fast enough to indicate a developing issue. And I still have the over temp sensor/alarm indicators and I know they work. (2 new impellers please!)
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Makes sense and no new holes :)

Roll on the real test :encouragement:
 
Well the spare bolt hole in the d4 inlet manifold is not m18, don't know exactly what size it is but it could be 10mm. 12mm or 14mm.

So I couldn't fit the wireless pressure gauge. Oh well back to the drawing board.
 
You can get the 1/8 npt adapters in any M size you need.

Or get a M20 to M whatever adapter.

What size socket goes on the current blanking bolt? Although not always....I have often figured out the bolt size based on which socket went on it.

I owe you a beer!
 
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It was an Allen key head, either 6 or 8mm. I'm going to take the bolt out again and measure it, but I'm guessing it was m10.
 
Right I've measured it and I'm reasonably sure it's M12, but what I can't be sure of is the pitch, so I'm going for it being a standard coarse pitch (1,75)
 
BruceK said:
Can any electrical guru help me out here. My VDO gauges arrived and they need a Molex 334720801 connector. Great, an obsolete connector type but I managed to find some on American Fleabay.
I have no idea on how to wire the connector up. I am a purely analogue system. Which is positive, negative and signal wire(s). All my other guages only have these three and separate additional for dash light.

This is the only instruction on wiring:
9Q8barZ.jpg


This is the sender unit:
a7W8r7y.jpg
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this VDO gauge also works with above sensor
TU00-0752-5207102

color coding for the gauge, a plug with short wires attached comes with the gauge, no need to order a seperate plug
VDO color coding jpg.JPG
 
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