10/25/2024
After Hurricane Helene and the subsequent power outages I was forced to use my old Westerbeke 4.4kw WMD diesel generator to charge the batteries. It was a good time to test this gen out since it only had light use previously. Battery charging is quite a power hog and it really loads the gen. I found that when the gen was loaded 2/3 or more it really started to smoke. And I actually wanted to load it more but was a bit worried about the old unit. So I kept loads to less than 3000 watts, which just adds to run time. It smoked bad enough that my dock mates would look at the boat like "are you sure your not on fire" but didnt want to say anything..lol.
Once dock power came on I decided to take 2 spare, old injectors and rebuild them to aid in troubleshooting the smoke issue. The nature of the smoke was that it was blackish, smelt of diesel and would give off a light sheen barely visible on the water. That along with the fact that it started slow, knocked lightly in an irregular manner nd the entire gen had irregular vibration on its mounts led me to suspect injectors first. Possible exhaust mixing elbow second.
With a little research I figured out the Westerbeke W13 4.4KW WMD is based off the Mitsubishi K2C engine found around the world. Westerbeke wanted $400 for each injector. With some research I found that you could get just the injector nozzles at the cost of 6 for $40. The nozzle is the critical part. The rest of the parts are much less critical. I rebuilt the spare injectors using new nozzles and flow tested them with good results. Put these rebuilt injectors in the gen and it fired right up and immediately ran better. But it still had about 1/3 of the smoke remaining. Better but not desired. After an oil flush and oil change with a bit of additive I fired it up and figured out I could run the air conditioner plus the hot water heater for a good load. After 20 minutes the smoke was greatly reduced. After 2 hours the smoke was nearly gone and was at an acceptable level. And the engine ran GREAT!. Hertz on the gen was very stable to within .1 to .2 loaded. RPM used to hunt up and down up to .5 or .6 hertz prior.
I took the original injectors home to flow test and one of them was very very bad and would continuously dribble fuel. I suspect the oil was likely diluted and the cylinders/valves etc had carbon build up. I suspect the more I run it loaded the better it will get. Anyways I thought I would share this one because it turns out...rebuilding Bosch injectors is super cheap and super easy.
My very old Westerbeke 4.4 KW WMD diesel generator was smoking excessively under load and was getting worse over time. It also smelled like diesel fuel and w...