Measure crankcase pressure

[skipperpete]

Well done , you’re making progress. The good thing is that by now , you know a lot about your boats machinery.

[ArranP]

Originally Posted by skipperpete

Well done , you’re making progress. The good thing is that by now , you know a lot about your boats machinery.

Here is a list of everything I've fixed or installed since April.
4 bilge pumps and bilge pump alarms including permenant supply circuitry
4 fresh water pumps
2 grey water sump box and pumps
2 electric toilets
1 deck washdown pump
4 electric winches / contactors / deck switches
Inverter
Electric general purpose sockets to saloon and 2 cabins
Solar panel and mppt charge controller
2 mattresses including linen quilts and pillows
1 tv
1 fridge
1 mircrowave
replaced 2 turbos
replaced 8 injectors
fixed transmission by replacing transmission filters to both STBD and PORT
replaced fuel filter
replaced 2x oil filters
fixed tender fuel pump
replaced tender battery cable
replaced tender gear shift/throttle cable
removed tender steering cable waiting for replacement cable to arrive.
installed tender automatic bilge pump
removed water maker motor/pump ordered replacement
sourced and sized replacement 48V self contained AC units.
sourced and ordered 48V battery bank.
sourced ordered and received kintic switches and led downlight drivers for ceiling lights.
sourced replacement fans.
had replacement curtains made
sourcing replacement leatherette for ceiling panels.
replacement autopilot
replacement sailbag and lazyjacks
fixed drainage problem from flybridge floor / cockpit ceiling when raining.

[ArranP]

Originally Posted by skipperpete

Pressure gauge and a tee piece with a small ball valve attached to the turbo oil pressure line. Rate of through flow can be measured by removing the cartridge drain pipe and making a dummy drain fitting with a hose into a container, don’t run it for longer than it takes to fill a one litre container.

Could disconnect from the engine block the oil return pipe put that into a 1 litre bottle, time how long it takes to fill 1 litre, then do the same on the STBD ( which is cooling fine ) and compare times.

[skipperpete]

Originally Posted by ArranP

Could disconnect from the engine block the oil return pipe put that into a 1 litre bottle, time how long it takes to fill 1 litre, then do the same on the STBD ( which is cooling fine ) and compare times.

Yes, that would work but normally the joiner in that drain line is fairly difficult to access on the average JH installation, is it better on your common rail engines?
Wow, you really have been busy, that’s an impressive list of upgrades and repairs!!

[ArranP]

Originally Posted by skipperpete

I don’t doubt that it failed,I just doubt that losing coolant flow to the turbine scroll waterjacket is the cause of yet another ( is this the second or third?) catastrophic turbo event. Did you re use any of the original turbo parts? Is the turbo lube oil flow substantial and at a high enough pressure? The axle runs on a wedge of rapidly replenished oil,..... (no contact with the bearing until shutdown and the main reason the turbo needs a 3-5 minute idle so it doesn’t melt the bearing as the heat runs out of the turbine into the now uncooled shaft).....that serves the dual purpose of cooling and lubricating.

An interesting day today.

In turns out the PORT turbo is in fact OK... the screaching noise was the tubing I had fitted from the air duct to the a turbo guage, it had burst open, that was the screaching noise rather like the noise a balloon makes when deflating.

I did find a problem with the cooling hose connection, I remedied that and now the PORT turbo is no longer overheating but keeping the same temperature as the STBD turbo.

Moving on, as I have said I have fited turbo gauges tee'd off the air ducting just on from the compressor air discharge to both the STBD and PORT engines.

The PORT side reading from the turbo guage is consistant with the Yanmar air pressure sensor at 12-14 psi, however the STBD ( that is the engin with the over fueling issue ) turbo guage shows 10psi whilst the Yanmar air pressure sensor is 4psi, so I swapped them over STBD / PORT and now the STBD engine Yanmar air pressure sensor is reading 0psi whilst the turbo guage is still 10psi ?? Not sure whats happening here, but will have to investigate further.

So it could be that the black smoke / over-fueling issue is related to this air pressure sensor not reading/getting the correct/full air pressure from the turbo.

[ArranP]

OK I have found source of the over fueling issue.

The air pressure sensor connects via an internal tube in the cylinder head through into the air manifold, this tube/hole had been covered over by a "self made" air manifold gasket, so the ECU sensor was getting no air pressure from the turbo/manifold and therefore it was restricting fuel to the engine.

Now that another gasket has been fabricated this time with a hole for the air pressure sensor, the ECU sensors is reading the correct air pressure and thus the ECU is now allowing more fuel through to power the engine.