Squealing from engine KAMD 43

[pondfish]

Hi all I have just bought an Antares series 9 on starting the engine every thing fine but when the revs go to 1700 rpm there is a loud squealing noise and the revs drop to about 1200 rpm,
It has three belts
1 v belt for alternator,
1 flat belt for water pump,
1 flat belt for compressor/boost pump,
the alternator belt was loose so reset that but still the same,
my worry is that a bearing might be gone can anybody help.

 

[BruceK]

check the primary belt from crank to water pump is not slipping. When that one slips as the supercharger comes on the screech can be deafening. Certainly made me stand up and take notice. Liable to happen after a winter on the hard or lengthy disuse when a bit of flash rust on the crank pulley develops to lubricate a bit of slip.

 

[Portofino]

Supercharger suppose to disengage around that higher rpm quoted and the turbo take over .SC used a solenoid in its wheel .
I’d look at that first to see if it’s letting go at the appropriate rpm ?
Check all the belts and the tensioners .Its a few years now since I got rid a KAD 300 set up , but the precision ,tuning , alignment, and lubrication of the 3 belts and pulleys , the co factor of the SC clutch was as scary as opening as Swiss watch movement.
I removed all the pulleys and de rusted them painted them with waxoil , and would regularly oil the bearings of the various pulleys and adjust the belts .Unfortunately I came round to the conclusion they were not fit n forget you have to be on them all the time to min down time .

 

[pondfish]

Thanks guy's the info is very helpful.

 

[kashurst]

when you tension the belts use a torque wrench as per manual. They have to be surprisingly tight.

 

[kashurst]

If you have just bought the boat probably worth buying new official Volvo belts incase someone has fitted something not to spec. People seem to get issues on the KAD series with cheaper parts. Make sure there is no dirt, grease or oil on the belt pulleys too.

 

[Momac]

Supercharger cut in should be just above 1500rpm which usually comes with a boost straight up to 2000rpm and certainly not a drop in revs .
Could the supercharger or the supercharger clutch be seized ?

Or perhaps the belt tensioner is worn/broken. I believe these can become worn. Maybe hope it is that as it’s the cheaper fix.

 

[BruceK]

Supercharger cut in should be just above 1500rpm which usually comes with a boost straight up to 2000rpm and certainly not a drop in revs .
Could the supercharger or the supercharger clutch be seized ?

Or perhaps the belt tensioner is worn/broken. I believe these can become worn. Maybe hope it is that as it’s the cheaper fix.

The SC cuts in at ~1800 rpm. If the main crank to water pump belts is slipping then the water pump pulley which drives the SC and alternator will lose rpm. Hence when the SC kicks in it loads the water pump pulley, slips and then the alternator slows showing lower rpm. The motor isn't actually dropping revs as the SC clutch takes it's timing from the black box and that from a gear hall sensor rather than the alternator which the dash instrument does. If the revs were dropping the SC would disengage and the slip and squeal stops.

 

[Momac]

The SC cuts in at ~1800 rpm..

I am thinking of my kad32 which is probably not the same revs for the supercharger cut in as a kad43 .

 

[BruceK]

I am thinking of my kad32 which is probably not the same revs for the supercharger cut in as a kad43 .

the 44 and 300 are different as well.

 

[alt]

From memory, the belts should be torqued to 42Nm

I keep one on the boat and I re-tention every few weeks.

I use genuine Volvo belts, I found the Gates belts started to squeal after a few hours. With the Volvo belts, I change every 2 seasons (I loosen them over the winter when the boat not in use)