Smokey KAD 300s

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frenzy

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I have 2 kad 300 engines on my boat.They have about 430 hours on each.Thay have always been a bit smokey ,but lately a bit more than normal i think.They seem to be running perfectly

Is this normal and is there anything i should be worried about.
 
I donk know the KAD300 engine but (rightly or wrongly) i am assuming it isnt a million miles different to the KAD32 just bigger? (im sure someone will correct me if im wrong, which i most probably am!!!)

Anyhow we have noticed with ours (KAD32) that it gets a little smokey after it has been plodding around on the rivers for a while but after a good run at higher revs it clears out and stops smoking. It still runs sweet whilst smoking but we see it as a good indication that it needs a good run. In fact its getting ready for another one now.
 
Same here my Kad 300s get a little smokey when I have been trolling for extended periods or just not used them. A good high throttle seems to clear them out.
 
Nick_H said:
Could it be the cold weather, maybe a bit of steam mixed in with the smoke makes it look worse?
Click to expand...

Good comment Nick.
I have been called to Peeps boats on a few occasions when the Temp drops
Sometimes the Owner has removed the Dinghy for the Winter months.
The exhaust gasses etc are then noticed!
The Ding, when on Snap Davitts and the like, creates a kinda 'vortex' and the 'smoke' dissipates in a different manner
When said ding is removed, this combined with the drop in Temp and the exhaust emmisions are more noticeable.
Food for thought frenzy?
 
We've also experienced increased sooting & smoke on the port side KAMD300. I'm suspecting an injector problem. Around 200 - 300 hours the was virtually no soot. Now approaching to 550 hours and the corner of the bathing platform looks pretty unpleasant after an hours drive.

We'll find out in two weeks time as I've asked an engineer to take the injectors out for testing.

The starboard engine is better with less smoke, but if it turns out that the injectors a to blame on the port side engine, I'm going to have the other one checked as well.

If they turn out to be ok, then I suppose that it's normal :(

edit: otherwise the engines seem to be working as per normal
 
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I Have KAMD 300s (shafts). They have always left plenty of grey on the transom after an hours run even from new. Now done around 300hrs. A little grey smoke on start-up from cold, but don't really notice smoke going along but do get a fair amount of white water vapour.

I may be wrong but I suspect these are intrinsically quite dirty engines, but probably not generally noticed if the hydro/aerodynamics wisk the smoke away under water. I believe part of the reason for going to the D series common rail design was because the KADs would never pass the emission regs - but there are others on here that are far better qualified to comment. Doesn't make them bad engines, but you do need to keep the strong detergent handy to keep the backside squeaky clean....
 
The smoke i'm getting is mainly white.Both engines are the same,I have noticed more smoke since i have taken the tender off for storage.Also because the boat is a flybridge and the weather is cold i have been driving from the inside and have noticed the smell more?
 
Did some one mention smoke.






IOMSeacat011.jpg
 
smoke

The engines usually smoke more when it's cold. This is because the charge air temperature is lower. This causes smoke! If the oil gets colder the pistons are colder asvell. This makes the smoke because of higher clearance and lower temperature of ignitinon start.

White smoke at startup is often caused by the air slowly leaking into the fuel pipe when the engine stops! On yachts is the fuel tank is often lower than the engine! A small air leak due to a rotten hose or connection provides fuel flow back to tank. The air that is inside the high-pressure fuel pipe retards the ignition so much that the fuel does not burn!

Another reason is that the wear is making the ignition later. Many adjust ignition timing to avoid the smoke! To test the nozzles requires good equipment when they are two steps nozzles! Leak before the 80-90% of the opening pressure can make smoke. Check the spray pattern! Have these jets Needle Lift Sensor?
 
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frenzy said:
The smoke i'm getting is mainly white.Both engines are the same,I have noticed more smoke since i have taken the tender off for storage.Also because the boat is a flybridge and the weather is cold i have been driving from the inside and have noticed the smell more?
Click to expand...

The smoke if white is poor atomisation of the fuel which could indicate a failing injector nozzle, if this is so and the boat is then used and put under load you may get a premature piston failure due to hosing of the injector, poor spray pattern will eventually burn to top off the piston.

Has the performance reduced lately?

I would get the injectors tested, and while this is being done get the valves checked as its easy to do this while the cover is off, will be part of a service, therev are other edc faults/ service procedures to check as well.

If your south coast based I can deal with it, send me a pm if your interested.

vp.
 
White smoke at startup is often caused by the air slowly leaking into the fuel pipe when the engine stops! On yachts is the fuel tank is often lower than the engine! A small air leak due to a rotten hose or connection provides fuel flow back to tank. The air that is inside the high-pressure fuel pipe retards the ignition so much that the fuel does not burn!

Another reason is that the wear is making the ignition later. Many adjust ignition timing to avoid the smoke! To test the nozzles requires good equipment when they are two steps nozzles! Leak before the 80-90% of the opening pressure can make smoke. Check the spray pattern! Have these jets Needle Lift Sensor?[/QUOTE]

Don't know what 'Ulyden' (norwegian for discord, unpleasant sound) has been reading but it he's very confused.
If white smoke is a sympton of an air leak then nearly every Volvo 40, 41, 42,43, 300 has an airleak as they nearly all smoke on start up.
And I don't know of anyone who adjusts the injection timing to avoid smoke, the procedure needs special tools and is beyond most owners anyway. If you retard the timing you will get more smoke if you advance it you will get heavy knocking which can destroy your pistons or big ends, so its not measured in anything so crude as degrees, but in thousands of an inch, so its critical to get it correct to get the best from the engine.
And Needle Lift Sensor has no relevance here, its only fitted to No 1 cylinder on KAD 42,43,300's and its purpose is to tell the ECU which is cyl No1 as there is no cam sensor on these engines.
I suspect most of this smoke is due to the cold ambient temps we are all experiencing just now, same as you see from your car on a cold morning.
 
I gave our KAD44 a good old winter "Italian Tune-Up" yesterday, with a good long blast from the Hamble down the Eastern Solent and out to the Nab and back.

Everything was running much smoother and less smokey (including me, as it was a bit fresh!!!!) after a good blast through!!
 
spannerman said:
White smoke at startup is often caused by the air slowly leaking into the fuel pipe when the engine stops! On yachts is the fuel tank is often lower than the engine! A small air leak due to a rotten hose or connection provides fuel flow back to tank. The air that is inside the high-pressure fuel pipe retards the ignition so much that the fuel does not burn!

Another reason is that the wear is making the ignition later. Many adjust ignition timing to avoid the smoke! To test the nozzles requires good equipment when they are two steps nozzles! Leak before the 80-90% of the opening pressure can make smoke. Check the spray pattern! Have these jets Needle Lift Sensor?
Click to expand...

Don't know what 'Ulyden' (norwegian for discord, unpleasant sound) has been reading but it he's very confused.
If white smoke is a sympton of an air leak then nearly every Volvo 40, 41, 42,43, 300 has an airleak as they nearly all smoke on start up.
And I don't know of anyone who adjusts the injection timing to avoid smoke, the procedure needs special tools and is beyond most owners anyway. If you retard the timing you will get more smoke if you advance it you will get heavy knocking which can destroy your pistons or big ends, so its not measured in anything so crude as degrees, but in thousands of an inch, so its critical to get it correct to get the best from the engine.
And Needle Lift Sensor has no relevance here, its only fitted to No 1 cylinder on KAD 42,43,300's and its purpose is to tell the ECU which is cyl No1 as there is no cam sensor on these engines.
I suspect most of this smoke is due to the cold ambient temps we are all experiencing just now, same as you see from your car on a cold morning.[/QUOTE]

Why I'm confused!

If you take a diesel engine connecting it to a water brake, measures the power, consumption, smoke, emissions,pressure in the cylinder, needle lift, injection pressure and videotapes exhaust from full load to idle! Next morning, change the ignition 2 degrees and repeat. The next day is new ignition timing and the weeks go. Next week new nozzles with larger flow and do the same again. New days with ignition adjustment. Then comes the week with various opening pressure at the nozzle! Next week new nozzlering on turbo! Larger plunger new measurements. water injection, exhaust recyceling, simple nozzles double nozzles, the years pass,old engines going, new comes new measurements, motors shall be approved for IMO EPA ABS DNV, etc. When you've been doing this in 20 years you get a little confused!

You get a little irritated that many engines smoke add the harbor because of trifles!

I gues that spannermann can read Norwegian! Adds the link to someone who has adjusted the ignition.

http://www.kamelia.nu/index.html?VPStartroyk.htm&2


The reason that I asked about needle lift sensor is that other engine manufacturers that use the same fuel injection pump uses this signal to compensate for wear in the mechanics! They run the closed loop of timing so it is always within 1 degree!
If you spannerman says that Volvo does not make it so you know these ecu well. Other engine manufacturers use it actively. Fuel temperature, the opening pressure of the nozzles, the viscosity of diesel, wear, teperatur changes in the position sensor does correction needed!(On other engines)
 
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Hi Ulyden, you obviously work with diesel engines, and I agree I hate to see marinas full of smoke when engines first start up, ( good reason to buy a Mercruiser!).
The Volvo egines with a lift sensor on No 1 injector (all KAD motors) have a very simple elecronic injection pump which has a limited amount of correction for fuel temp, pressure, and crank angle, but it is still totally dependant on the initial set up timing being correct and it can't compensate for wear and tear so therefore needs overhaul and recalibration eventually as it is basically a mechnical pump, so the smoke is really just the way it is with these engines as they rarely get enough hours on them to be worn, unless in commercial use.
The main function of the feedback on these Bosch pumps is to electronically control the governor and adjust the 'amount injected' more precisely to eliminate smoke. thats why KAD 44/300 engines run the compressor from cold up 60C engine temp to give an excess of air to try and cut down smoke when starting.
Its a very crude method compared to common rail systems where there is a lot more data being sampled and the ECU can steer the injection pressure, timing, and sequence much more precisely, even phasing it to give cleaner emmissions.
Its interesting that and old fully mechanical injection Mercruiser is cleaner on start up than a Volvo KAD or Yanmar, so a lot is down to engine design and construction also.
 
Mercs are a lot cleaner as they are indirect injection.

However years ago they tested the same boat a fairline corsica with 22o mercs and one with kad 42, the mercs used a lot more fuel, but the boat performed better with the mercs and gave hardly any smoke on start up, its a shame the base vm unit isnt as robust as a volvo can be. I stress CAN be, if looked after properly.
 
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