hotdog1948
New member
My 45 Yacht Westerbeke 12.6 BTD has been running fine for 2 years, but will not now start.
When trying to start, it blows the 8A fuse in the circuit.
I have replaced the fuel solenoid, and the battery, but the problem persists. After a lot of diagnosis, I have concluded the only option left is to replace the starter. Unfortunately, the starter is on the side of the generator against the forward engine room bulkhead. There is only about 12" of room to work in. A Volvo tech who has replaced the genset starter on another 45 Yacht said that it can be done without pulling the genset out. He said you can even do it without removing the enclosure sides, except for the top and the enclosure wall on that side of the generator. The enclosure wall on that side of the engine can just be removed and set down against the bulkhead there.
Three questions -
1. Has anyone replaced the genset starter on a 45 Yacht, and do you have any suggestions about how to proceed?
2. Can you confirm that the starter part number is 030593, and is it ok to purchase the Mitsubishi starter with same part number? (Several sources offer Mitsubishi starters with that part number, and list several gensets that it should work with, but they don't list the 12.6 BTD. I suspect any Mitsubishi 030593 starter will work.)
3. Should the voltmeter display a voltage when no button is pressed? (See background discussion below for clarification on this question.)
Thanks for any help,
Steve
* * * * *
Some Background:
The symptoms are quite unusual. The starter will engage and turn the engine. It will almost start, but then blow the fuse and stop. (It does this even when the leads from the alternator R terminal are disconnected.)
Schematics show that there is a circuit breaker, emergency stop switch and an 8A fuse in series with the pre-heat and start buttons. Pre-heat and start solenoids are downstream of the buttons.
Circuit breaker and emergency stop switch are fine.
Historically, the voltmeter always displayed ~14V, even if not connected to shore power so the dedicated 6A charger is not supplying the battery. (I have pics from 2 years ago that show the 12V even when not connected to shore power.) Pressing the pre-heat button would cause the voltage to drop some. Pressing the start button would reduce the voltage further. This is consistent with how a Westerbeke 30B Three auxiliary would start on a sailboat I used to own. It had a key. Turn the key, the voltmeter would come on and display 14V, etc.
On the 45 Yacht, there is no key for the genset; so it always displayed voltage on the meter. BUT NOW, no voltage is displayed on the meter, even after replacing the fuse, checking the breaker not tripped, and the emergency stop switch on. When pressing the pre-heat, the voltmeter is activated and it displays a voltage. Then, while holding the pre-heat on, pressing the start button causes the voltage to drop some and the engine to turn over and attempt to start. It then blows the fuse and stops. The weird thing is this behavior IS CONSISTENT with the Operators Manual, which states that pressing the pre-heat button will activate the voltmeter. This behavior is also consistent with all of the circuit drawings I've found, which show that the voltmeter is in series only with a circuit breaker, the emergency stop switch, the 8A fuse, and the two buttons (pre-heat and start). With no buttons pressed, the meter should not be energized at all. In parallel is a connection to the genset alternator R terminal, but that should not provide a voltage unless the engine is running. (I checked and there is no voltage on those leads or on the alternator R terminal for those leads when at rest. There is 12V on the alternator B lead that comes from the starter, and is just an extension of the battery lead.)
I wonder now if the previous behavior was not normal. That is, I wonder if the voltmeter should only register a voltage if the pre-heat is pressed. Can anyone confirm this?
When trying to start, it blows the 8A fuse in the circuit.
I have replaced the fuel solenoid, and the battery, but the problem persists. After a lot of diagnosis, I have concluded the only option left is to replace the starter. Unfortunately, the starter is on the side of the generator against the forward engine room bulkhead. There is only about 12" of room to work in. A Volvo tech who has replaced the genset starter on another 45 Yacht said that it can be done without pulling the genset out. He said you can even do it without removing the enclosure sides, except for the top and the enclosure wall on that side of the generator. The enclosure wall on that side of the engine can just be removed and set down against the bulkhead there.
Three questions -
1. Has anyone replaced the genset starter on a 45 Yacht, and do you have any suggestions about how to proceed?
2. Can you confirm that the starter part number is 030593, and is it ok to purchase the Mitsubishi starter with same part number? (Several sources offer Mitsubishi starters with that part number, and list several gensets that it should work with, but they don't list the 12.6 BTD. I suspect any Mitsubishi 030593 starter will work.)
3. Should the voltmeter display a voltage when no button is pressed? (See background discussion below for clarification on this question.)
Thanks for any help,
Steve
* * * * *
Some Background:
The symptoms are quite unusual. The starter will engage and turn the engine. It will almost start, but then blow the fuse and stop. (It does this even when the leads from the alternator R terminal are disconnected.)
Schematics show that there is a circuit breaker, emergency stop switch and an 8A fuse in series with the pre-heat and start buttons. Pre-heat and start solenoids are downstream of the buttons.
Circuit breaker and emergency stop switch are fine.
Historically, the voltmeter always displayed ~14V, even if not connected to shore power so the dedicated 6A charger is not supplying the battery. (I have pics from 2 years ago that show the 12V even when not connected to shore power.) Pressing the pre-heat button would cause the voltage to drop some. Pressing the start button would reduce the voltage further. This is consistent with how a Westerbeke 30B Three auxiliary would start on a sailboat I used to own. It had a key. Turn the key, the voltmeter would come on and display 14V, etc.
On the 45 Yacht, there is no key for the genset; so it always displayed voltage on the meter. BUT NOW, no voltage is displayed on the meter, even after replacing the fuse, checking the breaker not tripped, and the emergency stop switch on. When pressing the pre-heat, the voltmeter is activated and it displays a voltage. Then, while holding the pre-heat on, pressing the start button causes the voltage to drop some and the engine to turn over and attempt to start. It then blows the fuse and stops. The weird thing is this behavior IS CONSISTENT with the Operators Manual, which states that pressing the pre-heat button will activate the voltmeter. This behavior is also consistent with all of the circuit drawings I've found, which show that the voltmeter is in series only with a circuit breaker, the emergency stop switch, the 8A fuse, and the two buttons (pre-heat and start). With no buttons pressed, the meter should not be energized at all. In parallel is a connection to the genset alternator R terminal, but that should not provide a voltage unless the engine is running. (I checked and there is no voltage on those leads or on the alternator R terminal for those leads when at rest. There is 12V on the alternator B lead that comes from the starter, and is just an extension of the battery lead.)
I wonder now if the previous behavior was not normal. That is, I wonder if the voltmeter should only register a voltage if the pre-heat is pressed. Can anyone confirm this?
