fiskerendk
New member
Hi,
I have this KAD42 that makes a knocking sound.
Im pretty new to marine and Volvo Penta engines, and I have not much experience with diesel engines.
However it sounds bad to me, and from my experience with gasoline engines it could be a problem with a rod bearing. But also the sound is very constantly (ofcouse follows the rpm) no major changes in sound if its idle or under load.
And that challenges me a little, I have heard some warn rod bearings in my time with BMW.
But sound did varies as load increases or decreases dramatic making it more a rattle sound like than a knock.
But here its always a knock from the first fire up and down in rpm and with or without load.
I have by loosen the fuel lines and thereby narrowed it down to be at cylinder 2 becouse the knock stops when no fuel is supplied to that cylinder.
I have uploaded a video to youtube as can be seen here:
https://m.youtube.com/watch?v=O0Wt08c_fsQ
Also it tends to smoke white quite a bit when starting, however it could be do to the fact that I live in Greenland with water temperatures between 1-3 degreess celsius.
Also today trying to diagnose I took the boat out to the water 20min or so with trying everything between idle and full speed (34 knots) after aproximately 5min at full speed and down to idle the engine turned off right away and I had a pretty hard time to get it started again. Thats pretty unuseable becouse when I started the engine before the trip (cold start) it started at first crank, and that is pretty okay taking into account that outdoor temp was 4 degrees celsius and the engine have no glows.
The engine temp at running speed is sharp 80 degrees celsius and the oilpressure are between 4-5 bar (60-75psi) under load and 2-2.5 bar (30-35psi) idling.
Anyone have an idea to further throubleshooting or can tell me what it certainly is?
Best regards
Thomas
I have this KAD42 that makes a knocking sound.
Im pretty new to marine and Volvo Penta engines, and I have not much experience with diesel engines.
However it sounds bad to me, and from my experience with gasoline engines it could be a problem with a rod bearing. But also the sound is very constantly (ofcouse follows the rpm) no major changes in sound if its idle or under load.
And that challenges me a little, I have heard some warn rod bearings in my time with BMW.
But sound did varies as load increases or decreases dramatic making it more a rattle sound like than a knock.
But here its always a knock from the first fire up and down in rpm and with or without load.
I have by loosen the fuel lines and thereby narrowed it down to be at cylinder 2 becouse the knock stops when no fuel is supplied to that cylinder.
I have uploaded a video to youtube as can be seen here:
https://m.youtube.com/watch?v=O0Wt08c_fsQ
Also it tends to smoke white quite a bit when starting, however it could be do to the fact that I live in Greenland with water temperatures between 1-3 degreess celsius.
Also today trying to diagnose I took the boat out to the water 20min or so with trying everything between idle and full speed (34 knots) after aproximately 5min at full speed and down to idle the engine turned off right away and I had a pretty hard time to get it started again. Thats pretty unuseable becouse when I started the engine before the trip (cold start) it started at first crank, and that is pretty okay taking into account that outdoor temp was 4 degrees celsius and the engine have no glows.
The engine temp at running speed is sharp 80 degrees celsius and the oilpressure are between 4-5 bar (60-75psi) under load and 2-2.5 bar (30-35psi) idling.
Anyone have an idea to further throubleshooting or can tell me what it certainly is?
Best regards
Thomas
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