Fitting Charge Pressure Guage kit to KAD42

the VDO one i ordered does not tame a molex, its much smaller and by the looks of it specific to VDO
my other new VDO gauges also came standard with the same small plugs :)

the VDO gear is very sensitive to incorrect polarity, you can guess how i know, check 3x b4 you connect it
they are 'protected' against incorrect polarity for a few mins, after that they burn out, can't be that difficult to build in long term protection ?
 
Barbecue remote engine temp display.

Apologies for the delay. Finally got around today to installing the Barbecue remote temperature sensor system as mentioned back in the spring. Modified the supplied stainless steel probes by soldering on the 100K ohm NTC sensors from Ebay. After a lot of thought in the end I decided to embed the tiny sensors in Araldite Rapid epoxy in the top most plug in the turbo charger.

This gives a very easy install on my boat and the wires are well away from the belts and chargers on the front of the engine. Also the turbos are the hottest component in the cooling system so any temp issues will show up there first. If the sensors break I can just ping them out with a small screwdriver. On a KA(M)D 300 the temperature sensor for the ECU is very close by in the exhaust manifold cooling system, so top of turbo seems a sensible location.

sensor in the turbo casing plug
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the remote sender unit mounted in the engine bay - a particularly high quality installation I think you will all agree
LrPQbQC.jpg


the remote display panel - food = port, barbecue = starboard. I haven't decided on its permanent position just jet (as I suspect it will not survive the sea air for very long)
ShDMbwj.jpg


As you can see it works really well. I cross checked the turbo exterior temp with an IR thermometer and also checked the thermostat housing. At 3200rpm all temps were within a degree of each other @ 80 degs C. The picture shows temps back in the harbour and its all cooling down a bit.

Installation time about 40 mins, cost @ £35. It all runs of AAA batteries so easy to run and no other wiring required.
 
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If the turbo external temp is noticeably higher there could be air in the turbo cooling circuit. To check, slacken the banjo bolt on the pipe that goes back to the expansion tank and check antifreeze mix comes out.
However depending on the air circulation around the turbo, measurement error with IR thermometer etc, I don't think that @ 5 degrees more matters if the main engine is @ 80 - 85 degs C.
I have put black insulation tape on the various engine parts to get a hopefully a more precise IR reading too.
 
'If the turbo external temp is noticeably higher there could be air in the turbo cooling circuit. To check, slacken the banjo bolt on the pipe that goes back to the expansion tank and check antifreeze mix comes out.'

with the engine running ?

yes that's probably a good idea in case there is a bubble that's stuck, the water flow might shift it - however do it cool not hot.
what temp difference are you getting and how are you measuring it?
 
As you can see it works really well. I cross checked the turbo exterior temp with an IR thermometer and also checked the thermostat housing. At 3200rpm all temps were within a degree of each other @ 80 degs C. The picture shows temps back in the harbour and its all cooling down a bit.

Installation time about 40 mins, cost @ £35. It all runs of AAA batteries so easy to run and no other wiring required.

K,

nice install, but I guess what you do get is general coolant temp in these two gauges and not EGT or anything close to it, right?
so it's more of a seawater coolant warning thing (blocked intake, shreaded impeller)

I can see the thermocouple surviving nicely in epoxy there, not sure about the sender in the bilges though :rolleyes:

cheers

V.
 
K,

nice install, but I guess what you do get is general coolant temp in these two gauges and not EGT or anything close to it, right?
so it's more of a seawater coolant warning thing (blocked intake, shreaded impeller)

I can see the thermocouple surviving nicely in epoxy there, not sure about the sender in the bilges though :rolleyes:

cheers

V.

No it definitely doesn't measure EGT - the core plugs in the turbo close off the fresh water cooling so the plug/sensor is surrounded by antifreeze circulating around the engine. The kit is obviously cheap stuff of ebay and I don't expect it to last long - it's just a bit of fun inspired by FARSCO using tyre pressure sensors to measure boost pressure. I want to know engine temps on the flybridge as there is only a rev counter and the alarm warning panel. This is a very easy and cheap temporary solution.

However back to EGT measurement. I have been measuring all sorts of temps over the summer with my IR thermometer. Particularly the pipe from the turbo to the charge air cooler. In the picture below you can see a band of black tape on tube from the turbo to the charge air cooler. Just above the gearbox cooler. This point is where I measure turbo air temperature.

PP3uvtA.jpg


I have established that with a clean hull, calm sea, at 18 knots my engines are doing 3200rpm, 85 l/hour and that black tape is at 130 degs C. Comparing that fuel burn and engine speed to the volvo prop demand curve my engines are doing pretty much exactly as volvo predict. With a clean hull etc both engines hit 3800 rpm again as volvo expect.

So I now know that if the engines are at 3200rpm the air coming out of the turbo with ideal conditions is 130 C. Ideally both engines should read the same. (they do) I now know that my engines in this mode of operation are well with in the volvo spec so should burble away quite happily.

Now its September the hull is getting fuzzy and the turbo air temp is now at 134 C and fuel burn is slightly worse.
I was also able to determine a fuel consumption difference/problem between engines a few weeks ago when the starboard engine was starting to use more fuel going by the fuel gauges (not brilliant gauges, but good enough to indicate something amiss)
I measured the turbo air temps. Port was 110 C, Starboard was 140 C so starboard was working harder and was using more fuel.
New air filters cured the problem both engines back to @ 130 and fuel burn equal again. Looking at the air filters I couldn't tell the difference but the engines could.

EGT temperature is related to engine load, more fuel burnt, faster/hotter turbos = higher EGT
Turbo air temperature is determined by how hard the engines are working
So by knowing what the turbo air temp is under normal conditions I can infer EGT temp is OK from the volvo prop demand curve. As engine loads rise with fouling etc I can see the increase in work and therefore EGT by observing turbo air temp and decide if/when I am pushing it too hard / time for a hull clean etc /identify fuel and air filter issues developing.

A very useful temperature to know and much easier to measure than EGT directly.
I might do something more professional over the winter to display engine temp and turbo air temp at the flybridge.
 
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Buy another bbq kit...one per engine

Food.....turbo coolant temp

BBQ.....remove one of the blanking bolts from the intake manifold, drill a small hole for the probe, epoxy it In place....sorted.

It’s only measuring air temp after the intercooler and has to be strong enough for what....2 bar max? :D

If you want before the intercooler....there’s a blanking bolt on the back side of the intercooler housing facing the engine (top right in you picture) but it’s smaller bolt. Ask how I know....found it in the bilge and thought where’s that from. Boost was down :):):)

If it doesn’t work out.....new bolt.
 
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Thanks for the info on the amazon site. I will get one and see if I can make it a bit more rugged to endure sea air.
that should work really well. I have been out today on the boat checking that I can read my iphone display if it's dark text on a white background. Yes I can so that's my winter project sorted.

re: engine bay - thanks, it's why I chose this boat, everything else for me was secondary. It just makes everything really really easy.
 
I don't know lots of variables involved. Try it and see what you get. Probably similar but I suspect you will be going faster at 3200rpm
 
I'm trying to find where I read what the air temp should be after the CAC / intercooler. Can anyone point me in the right direction or advise?
 
I'm trying to find where I read what the air temp should be after the CAC / intercooler. Can anyone point me in the right direction or advise?

no, but definitely nowhere near the values K is getting!
iirc my turbocharged highly modified car (ok petrol) wouldn't tolerate temps over 50-55C

For that you should try to add a proper probe and measure inside and not the body.
I know it cannot be done on the turbo, and looks like there's no elbow on your engines so no space of single walled exhaust gasses only tube to drill and tap :(

I think you can only use it the way K explained, as a good alternative measure of engine temp, not inlet air temp, not EGT, nothing.
I'm struggling a lot with time as I have a couple of deadlines to deal by Fri, if I find a few mins, I'll point to the k-type thermocouples I bought and proved good quality for you to test (assuming the box reads them). I'd previously bought some crappy k-type ones that were simply a waste of time (not money though, they were peanuts....)

cheers

V.
 
I measured the inlet manifold after the intercooler at 60 deg Celsius. The turbo to intercooler at 127 Celsius. So a nearly 70C drop. Ambient temps in the engine room about 35C, Sea Water about 15C and air temp about 18C.
I seem to recall somewhere that the inlet temps should be no more that about 20C ??? above ambient but not sure if that is engine room ambient temps or outside ambient temps.
 
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