Measure crankcase pressure

[ArranP]

Is this blue or white smoke ?

https://photos.app.goo.gl/orbpzLJ8YdkTFf456

Video is of PORT engine WOT producing 2,700 rpm and 10-15 psi of boost. These engines 4JH110 should attain 20 psi of boost and 3,200 rpm.

I am thinking that this is white smoke and therefore will try new injectors.

This is same engine but at 2,000 rpm.

https://photos.app.goo.gl/TRmJXvXHskB29ThUA

[sinnerman]

Looks like White smoke

[sinnerman]

When I pulled my injectors on my engine, (Westerbeke/Universal 3 cylinder, no turbo), I also as you did checked the compression and additionally I adjusted the valves. All three of my injectors, when tested in the shop had issues.

One other "off the wall" test I performed, was to check the output of the injector pump. I taped plastic cups to the injector lines where they would connect to the injectors and cranked the engine over several times.

The fuel from the injector pump was collected in the cups and I compared the amount of fuel in the cups to see if all three had the same amount of fuel.

My reasoning for performing this test is that the injector pump piston springs sometimes fracture/break. This would result in less fuel /injector pressure coming out of the pump for the cylinder with a bad spring.

All three plastic cups had exactly the same amount of fuel in them so I concluded that the pump was OK.

BTW, the injectors themselves can tell you if you have too much fuel/combustion issues in that cylinder. The tips of the injectors in a properly firing cylinder have a light brown color. Injectors in a cylinder with poor combustion have black carbon on them. At least that is my experience.

My two cents.

cheers

[FPNC]

Originally Posted by ArranP

Is this blue or white smoke ?
I am thinking that this is white smoke and therefore will try new injectors.

This looks like white steam. Are you sure that you are not chasing exhaust water steam? Is there any oil slick on the water to indicate unburned oil or diesel?

[ArranP]

Originally Posted by FPNC

This looks like white steam. Are you sure that you are not chasing exhaust water steam? Is there any oil slick on the water to indicate unburned oil or diesel?

There is no slick in the water, the turbo turbine housing is at 220 degrees C when operating.

[ArranP]

Originally Posted by FPNC

This looks like white steam. Are you sure that you are not chasing exhaust water steam? Is there any oil slick on the water to indicate unburned oil or diesel?

The engine is loosing its water coolant, so this then is probably the reason for the steam, i.e. the water coolant is being lost via the turbo cooling circuit and outed through the mixing elbow as steam.

The new turbo running at 220 degree has ceased, probably due to overheating.

Therefore coolant is entering the turbo but for some reason is being lost by the turbo through the mixing elbow as steam.

I have purchased another replacement turbo but before fitting it, I should check that the coolant return line from the turbo through the heat exchanger is not blocked, if not then it must be that that particular turbo was defective prior to the overheating, by already having the coolant leak.

[skipperpete]

I’d be very surprised if the turbo failed because of overheating at 220°C, most turbo’s are not fitted with a cooling water jacket on the hot side and reach operating temps well over 500°C.......like this Mitsubishi generator.

[ArranP]

Originally Posted by skipperpete

I’d be very surprised if the turbo failed because of overheating at 220°C, most turbo’s are not fitted with a cooling water jacket on the hot side and reach operating temps well over 500°C.......like this Mitsubishi generator.

The turbo has failed, it was smoking from the exhuast turbine for 10 minutes before it gave out a screach then little to no boost once the screaching started.

[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.

[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?

It was a complete replacement, none of the parts from the old turbo were used except for the connectors and pipes / hoses.

Originally Posted by skipperpete

Is the turbo lube oil flow substantial and at a high enough pressure?

How to test ?

[Bowdrie]

Originally Posted by skipperpete

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.

Six pages, (so far,) of this thread has reinforced what I read many years ago in a design book by the late William Garden.
I'll have to paraphrase, but the bottom line was, "Nothing worse than being stuck in Mombasa with burned out turbo bearings".
There isn't any practical reason on this green earth, (or the blue sea,) that a cruising sailboat that has engines with only ~80HP needs turbos on them.

[skipperpete]

Originally Posted by ArranP

It was a complete replacement, none of the parts from the old turbo were used except for the connectors and pipes / hoses.







How to test ?

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. It’s very rare to have a turbo to fail on its first startup..... I’ve never had it happen, ever..... even with aftermarket cheapies ....and even more rare when the same engine has more than one turbo failure in only a few hours of runtime.
I suppose it’s possible that your new turbo had a flaw in the waterjacket that allowed the coolant direct access to the turbine wheel but you’d be having a general engine overheat due to coolant loss in just a few minutes after startup, so I’m thinking perhaps an airlock in the water jacket , but an oil supply issue that made the turbo squeal (and possibly seize). Incidentally, a blocked drain line presents as a spectacular amount of oil in the mixer elbow and Aqualock, .....this I have had happen.
Hope you can get it solved.

[skipperpete]

Originally Posted by Bowdrie

Six pages, (so far,) of this thread has reinforced what I read many years ago in a design book by the late William Garden.

I'll have to paraphrase, but the bottom line was, "Nothing worse than being stuck in Mombasa with burned out turbo bearings".

There isn't any practical reason on this green earth, (or the blue sea,) that a cruising sailboat that has engines with only ~80HP needs turbos on them.

I’m inclined to agree with you Bowdrie but it’s getting harder to buy an engine WITHOUT a turbo these days and should you ever find yourself stuck in Mombasa with a dud turbo, it’s fairly easy to extract the cartridge and blank off the hole left by the turbine, plug the oil line and drain pipe, put a screen over the air intake and you’re good to go .......at 60% power.

[Bowdrie]

Originally Posted by skipperpete

I’m inclined to agree with you Bowdrie but it’s getting harder to buy an engine WITHOUT a turbo these days

Touche, alas, but you've got me there.

[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. It’s very rare to have a turbo to fail on its first startup..... I’ve never had it happen, ever..... even with aftermarket cheapies ....and even more rare when the same engine has more than one turbo failure in only a few hours of runtime.
I suppose it’s possible that your new turbo had a flaw in the waterjacket that allowed the coolant direct access to the turbine wheel but you’d be having a general engine overheat due to coolant loss in just a few minutes after startup, so I’m thinking perhaps an airlock in the water jacket , but an oil supply issue that made the turbo squeal (and possibly seize). Incidentally, a blocked drain line presents as a spectacular amount of oil in the mixer elbow and Aqualock, .....this I have had happen.
Hope you can get it solved.

This is work to both the PORT and STBD engines/turbos... I have replaced original turbos on both engines due to them being submerged in seawater they were no longer fit for purpose. The replacement PORT turbo reached 200C and has ceased, the replacement STBD turbo reaches 80C and seems ok..... so far.

I will check and compare the oil and water flow to the turbos on both STBD and PORT engines before fitting another new PORT turbo.

The replacement PORT turbo whilst it was working was producing 15psi boost, engine reaching 2700rpm but omitting what appeared to be steam coming from the exhaust, video clip here https://photos.app.goo.gl/JqHSQfCftZEuCQW36

The replacement STBD turbo is producing 10psi boost and engine is now reaching 2300rpm but stilll black smoke, however load is now only 70%. So the black smoke issue or over fueling is still present on the STBD engine, but it is now getting more air from the turbo and thus maximum rpm has increased from 1900 to 2300, so other than pulling the head to inspect the pistons / rings and/or replace the head gasket, not sure what more can be done here.... its had a new turbo and new injectors but still black smoke however rpm increase rom 1900 to 2300rpm after fitting the new turbo.

Optimally rpm should be 3200 and boost should be near to 20psi.