KAMD44P-B turbo boost

Does anyone have a boost/rpm/temp chart for a Volvo KAMD44P-B? I am having trouble making my wot rpm and am suspicious of my turbo.
Thanks,
Andy

Re: KAMD44P-B turbo boost

what pressure are you getting?

Re: KAMD44P-B turbo boost

Making a boost tester now out of one of the plugs in the intake manifold, I will let you know.

Re: KAMD44P-B turbo boost

What makes you suspicious of your turbo? Low boost does not usually mean you have a turbo problem, it usually means you have a fuel problem Boost comes from exhaust, comes from combustion. It's one big cycle, and of course you need to get the air to burn the fuel to make the boost. Turbos fail for sure, but are not usually cause of low boost. They often leak oil or fail first, or get something in them. A quick inspection of the cold side visually may be best. Checking boost will prove one thing, low boost. What you really have is low power, right? Have you had higher WOT RPM before?

I know this sounds like a circular argument, but if you have low boost it does not prove that your turbo has anything wrong with it. Do these have a waste gate?

Re: KAMD44P-B turbo boost

Here is the chart.

Re: KAMD44P-B turbo boost

Thanks Don, does the boost change with rpm, or should it be consistent throughout the rpm range?

I suspect the turbo because I have some soot buildup on the transom and the last time I had the elbow off there was some corrosion in the turbo housing. If it is the turbo, I am going to have a riser made before replacing.

Thanks for the replies,
Andy

Re: KAMD44P-B turbo boost

Did you see the note about boost pressure being checked only above 3100 RPM?

Under load, everything changes with RPM, but since the Volvo has a supercharger for lower RPM (where turbo boost alone would be low), they are suggesting that boost numbers below there are somewhat independent of the turbo and could be misleading. Also, since propeller load is linear with RPM, typically in a marine application, boost would be highest at WOT RPM, and zero at idle, with a somewhat straight line in between. Climbing a swell (or hill in wheeled application) boost would rise some at lower RPM if more fuel was applied, either by the operator or an isochronous governor.

Again, the supercharger changes this equation some. The idea behind the supercharger is to compensate for low speed turbo lag and lack of boost at low RPM, so in the case of the Volvo, it is different than a typical diesel with a turbo only.

Re: KAMD44P-B turbo boost

Thanks QC, I'm familiar with the supercharger/turbo setup. I'm having a tech put a vodia on the motor this week to test sensors, boost pressure and fuel flow. I will post the results.

BTW, the boat is a Carolina Classic 25 and weighs in around 9,500 pounds loaded. I currently run a C2 prop set and could only turn 3,700 rpm fully loaded with 4 big guys. Earlier in the season, cold air and water, I could make 3,900 rpm with an A3 set. I think I have an issue on the air side.

Thanks again,
Andy

Re: KAMD44P-B turbo boost

was this a gradual issue, or did you change where you fueled up?

what is the cetane of the fuel your using? have you checked the fuel system for restrictions?

Re: KAMD44P-B turbo boost

It has been gradual, the last time I filled up I also loaded up, that's when I could only turn 3700 rpm (so that was pretty immediate). I changed the fuel filters today, but couldn't fuel up due to really low tide. I hope to fuel up by Friday and see what happens with full tanks of fresh diesel and new filters. Hopefully the tech will be able to hook it up to the vodia this weekend. I will post when I have more info.

Thanks for all the great info and suggestions.
Andy

Re: KAMD44P-B turbo boost

Scanman1973 said:

It has been gradual, the last time I filled up I also loaded up, that's when I could only turn 3700 rpm (so that was pretty immediate). I changed the fuel filters today, but couldn't fuel up due to really low tide. I hope to fuel up by Friday and see what happens with full tanks of fresh diesel and new filters. Hopefully the tech will be able to hook it up to the vodia this weekend. I will post when I have more info.

Thanks for all the great info and suggestions.
Andy

Click to expand...

You are having black smoke and can't reach WOT of 3900 rpm. You stated ". I currently run a C2 prop set and could only turn 3,700 rpm fully loaded with 4 big guys. Earlier in the season, cold air and water, I could make 3,900 rpm with an A3 set."

So you changed the props and immediately lost WOT rpm. It sounds like you put the wrong prop on and the black smoke indicates the engine is working harder than it should. Put the A3 set back on and see if that changes things back to the way they were.

Having said that the first thing to do is check the bottom is clean ...i mean CLEAN!! Otherwise everything you do will just be wasting time and money if you find later all she needed was a bottom wash and some antifoul.

If the bottom is clean and the props are correct, then start looking at the turbo. Your EDC (computer) determines fuel flow based on a number of parameters (fuel temp, air pressure etc) and signals the fuel pump to deliver the appropriate quantity of fuel. If the turbo is faulty (worn turbine blades for example) exhaust will simple start bypassing the turbine and this will reduce turbine speed. This in turn will reduce compressor speed and consequently boost. The EDC always assumes good boost for specific rpms and will signal the fuel pump to deliver the appropriate fuel. Unfortunately, it will be too much for the low boost the engine is now getting and this will create an low air/fuel ratio resulting in unburnt fuel. This in turn will present itself as black smoke. The engine will not reach WOT in this condition. Pull off you exhaust elbow and inspect the turbine for wear and wiggle the turbine axis up and down, sideways and in and out. There should be little or no play.

Turbo exhaust outlet corrosion is common in these engines. As the corrosion swells it starts to wear the turbine blade tips, but it's not the corrosion which be the problem. Its the clearance between the blade tips and the housing which should be very little.

So, check the bottom is clean, check you have the correct propeller fitted (the one that last gave you 3900 rpm) and check you turbine blades. Fuel filters are not the problem.

Re: KAMD44P-B turbo boost

Lord Farringdon said:

You are having black smoke

Click to expand...

Did you get that from the soot on the transom comment? I was looking for black smoke concerns and didn't really conclude that there was any serious amount.

Lord Farringdon said:

Your EDC (computer) determines fuel flow based on a number of parameters (fuel temp, air pressure etc) and signals the fuel pump to deliver the appropriate quantity of fuel.

Click to expand...

This seems contradictory with this:

Lord Farringdon said:

The EDC always assumes good boost for specific rpms and will signal the fuel pump to deliver the appropriate fuel. Unfortunately, it will be too much for the low boost the engine is now getting and this will create an low air/fuel ratio resulting in unburnt fuel.

Click to expand...

It does have a MAP sensor, right?

Re: KAMD44P-B turbo boost

QC, I think the problem with this engine is that it is part mechanical and part computer controlled. It uses throttle position as an input and assumes boost and will match with fuel, when the boost is low it runs too rich and the temps go way up. I haven't found a good way to install a pyrometer, because all the exhaust is jacketed or wet. The D series is now completely electronic, and common rail, to address this issue.

As for props and bottom, I should have stated... The A3 set made wot in the early season, then the rpms started to drop at wot, so I put the C2 set on and was able to make wot. The bottom has minimal growth, I scrubbed the bottom last month and it had some slime, but not too bad. I will clean it again.

I had a tech hook up the vodia yesterday, I will post the results later today.

Also, one of the reasons I suspect the turbo is that the previous owner had a similar issue, but worse, and eventually found it to be the turbo.

Thanks for everyone's help,
Andy

Re: KAMD44P-B turbo boost

Cool. Thanks for the info. Good luck

Re: KAMD44P-B turbo boost

The Volvo tech took the boat out and hooked up the Vodia to the motor, now he has to upload data to Volvo for a print out?? I will post with results.

Re: KAMD44P-B turbo boost

Finally got the data back from the tech, here are the numbers:

Called for RMP: 4000
Actual RPM: 3872
Boost: 155 kpa or 22.4 psi
Fuel rate: 14.8 gph (not sure if this is actual or what it should be at 4000 rpm)

Here is another data set
Called for rpm: 1685
Actual rpm: 1691
Boost: 114 kpa or 16.5 psi
Fuel rate: 2.91 gph

Called for rpm: 3527
Actual rpm: 3526
Boost: 124 kpa or 17.98 psi
Fuel rate: 12.42 gph

So I'm not making wot rpm with a C2 prop set, what do you think my problem is? Looks like my boost is a little low at higher rpms??

Thanks,
Andy

Re: KAMD44P-B turbo boost

is this a wastegated turbo?

Re: KAMD44P-B turbo boost

No waste gate on the kamd44.

Re: KAMD44P-B turbo boost

Don't we need the ambient temperature to correct the boost numbers?

Edit: Actually not ambient, intake air temp, so we need the temp inside the engine room when the data was taken.

Re: KAMD44P-B turbo boost

The turbo temp, I'm assuming its after the charge air cooler, was 40, so adjusted (thanks Don) I think it would be about 160 kpa or about 23 psi.