KAD44 issue

supercharger clutch worn out? if possible run the engine with the hatch up and look for sparks as the supercharger clutch engages
 
you can only buy the complete assembly, number 11 in a circle.
it is possible to see the thin layer of friction material without taking the clutch apart if you look in the slight gap between 14 and 17. the friction stuff is on 17. If you drive the boat in displacement mode (slowly) make sure the revs are not sitting at 1000 rpm as this is where the clutch engages. (I think' check manual - it's 1000 on a kad300) If you drive at 1000 rpm the clutch will keep engaging and disengaging as the rpm varies very slightly under load. It may be it's just got a bit cooked if used without understanding this and started to slip as it has overheated.
 
It was 1400 rpm on my old DPH KAD 300 twin .
Probably varies a bit .
There’s been rigorous debate about D speed sub supercharger cut in our point on here many times .
I,am sure I read in my manual 2003 , they were “ high speed diesels “ designed for running constantly north of 3000/3200 , SC cut in @1400 and passed boost job to the turbo @ 2600 or there about s so dropping to 2600 the cut out and hovering there is just as bad friction material life wise as the engagement speed .
Avoid engagement AND disengage rpms what ever they are ?
 
Another reason possibly for the symptoms if the screeching comes on when cruising , up on the plane is a turbo is on its way out , dropping boost so the SC starts or try’s to engage .Its a bit masked by the other ( good ) engine initially.
But eventually as time passes it be becomes apparent.
So the knackered SC clutch is caused by a increasing lazy turbo .
 
Portofino said:
It was 1400 rpm on my old DPH KAD 300 twin .
Probably varies a bit .
There’s been rigorous debate about D speed sub supercharger cut in our point on here many times .
I,am sure I read in my manual 2003 , they were “ high speed diesels “ designed for running constantly north of 3000/3200 , SC cut in @1400 and passed boost job to the turbo @ 2600 or there about s so dropping to 2600 the cut out and hovering there is just as bad friction material life wise as the engagement speed .
Avoid engagement AND disengage rpms what ever they are ?
Click to expand...

That's not the case, the manual doesn't say anything like that.
 
Portofino said:
Another reason possibly for the symptoms if the screeching comes on when cruising , up on the plane is a turbo is on its way out , dropping boost so the SC starts or try’s to engage .Its a bit masked by the other ( good ) engine initially.
But eventually as time passes it be becomes apparent.
So the knackered SC clutch is caused by a increasing lazy turbo .
Click to expand...

Thanks - I've head of those 'hunting' symptoms before but I don't believe mine suffers from it. But it's perfectly possible that the clutch is on its way out.
 
If anyone can look whilst going along I think you will save yourself cash or where is noise coming from and where is “ smoke” coming from. Assume it was ok to Ibiza ?

Re the revs all over the place were they or was it just The Gague ?

If just the indication you are back to alternator again. Knackered bearings and stopping? Stops belt screeches and “smoke”
 
jrudge said:
If anyone can look whilst going along I think you will save yourself cash or where is noise coming from and where is “ smoke” coming from. Assume it was ok to Ibiza ?

Re the revs all over the place were they or was it just The Gague ?

If just the indication you are back to alternator again. Knackered bearings and stopping? Stops belt screeches and “smoke”
Click to expand...

Runs fine at speed (trip to / from Ibiza was fine) which is always encouraging.

It's erratic revs, not just indication. Problem is occurring at tickover and when running at low speed.

I'm not back out until August so will leave our chap to sort it out. Most likely causes seem to be...

1) blocked fuel filter - could explain erratic revs and smoke
2) knackered alternator - could explain screeching, belt dust and erratic revs
3) Knackered compressor clutch - ditto
 
Just another possible cause of the revs jumping up and down. Inside the racor 500 filter assembly is a little alloy ball and a red rubber seal thing. It is there to act as an anti-run back device if you leave the boat for a while with low fuel levels. They have been known to play up. I was advised by local Volvo (Oscar Marine - Andy knows him well) to take the ball and seal out - which I have done. I don't think it's the ball per se, I suspect it is because the path for the fuel past the ball is not that big so if a lump of crud comes through it can get stuck etc.
 
petem said:
That's not the case, the manual doesn't say anything like that.
Click to expand...

I had 9 years ( someone give me a medal :)) with a VP outdrives set up and never had a SC clutch issue .
Either went at 120O rpm sub SC cut in D speeds or north of 3000 full planing , loadsa of head room from the 2600 ?
Never in-between.
Which tbo was a total PITA in big seas ,

I guess with 3 users in all sea states every guys thinks it’s the other when an issue pops up .
So your VP issues of miss use will surface more than an single owner lavishing love on it .
Not being critical just realistic.
 
1) blocked fuel filter - could explain erratic revs and smoke
Unlikely.

2) knackered alternator - could explain screeching, belt dust and erratic revs
Very Possible. Also check the idler/tensioner pulleys on the belt runs - good ones should be only warm, bad ones get hot and screechy.

3) Knackered compressor clutch - ditto
Also possible.

.
 
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Portofino said:
I had 9 years ( someone give me a medal :)) with a VP outdrives set up and never had a SC clutch issue .
Either went at 120O rpm sub SC cut in D speeds or north of 3000 full planing , loadsa of head room from the 2600 ?
Never in-between.
Which tbo was a total PITA in big seas ,

I guess with 3 users in all sea states every guys thinks it’s the other when an issue pops up .
So your VP issues of miss use will surface more than an single owner lavishing love on it .
Not being critical just realistic.
Click to expand...

If my partner wishes to cruise at displacement speeds (with supercharger on) then I'm not going to discourage him based on some Internet folklore. And to be honest, if it is the supercharger clutch then it's lasted 16 years and a replacement is only £330 (so split between the three of us not much dearer than a decent lunch).

As for syndicate boats, we all agree that boats like to be run regularly and syndicate boats generally are (as well as being fastidiously maintained).
 
FlowerPower said:
1) blocked fuel filter - could explain erratic revs and smoke
Unlikely.

2) knackered alternator - could explain screeching, belt dust and erratic revs
Very Possible. Also check the idler/tensioner pulleys on the belt runs - good ones should be only warm, bad ones get hot and screechy.

3) Knackered compressor clutch - ditto
Also possible.

.
Click to expand...

Thanks, so alternator or pulley would be your guess?
 
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