Yanmar 3ym30 serpentine belt installation

[Be Free Sailor]

Hi guys, I own a Lagoon catamaran, and ever since buying the boat, I have been struggling with slipping alternator V-belts, black belt dust everywhere in my engine rooms, and loss of charging current to the batteries.
Especially after upgrading the Lead/acid batteries for LiFePO4, the situation became even worse, due the increased current draw from the alternators.
Replacing the V-belts several times during the season is a real pain.
I found a good solution, and I want to share my experience;
After some research, I decided to install Electromaax serpentine belts and pulleys on both engines.
I also added the adjustable belt tensioner from Electromaax.
Installation was fairly easy, and took around 2 hours per engine.
Some points;
1. Removing the nut of the alternator axle was not easy, and I ended up getting an impact tool, then it was no problem. The V-belt pulley was replaced with a machined serpentine belt pulley supplied by Electromaax.
2. The Yanmar plastic belt cover needs to go, and will not fit after the installation is complete, because the new serpentine belt is much wider than a V-belt.
3. The fresh water cooling water hose, running next to the belt, needs to be pulled away from the new serpentine belt, or it will chafe. I used a cable tie to hold it away, and will soon add a new bracket to hold the water hos ein place.
4. Replacing the fresh water pump pulley was very easy, only the old bolts had to be re-used, because the supplied bolts were too short, but that was no problem at all.
5. The flywheel pulley was just slipped over the existing pulley, and fixed with 4 bolts supplied in the kit.
6. Installing the new pulley on the alternator shaft was easy, but I had to machine an extra disc, to enable the new pulley to be fastened correctly. The thickness of the new pulley was 3 mm thinner than the V-belt discs, and did not compress/fixate the new pulley, because the thread on the alternator shaft was not long enough to allow good compression of the new pulley.
All in all I am very satisfied, and now looking forward too cleaning the engine bays and enjoying the new Electromaax serpentine belt installation!
BR/ Niels