Generator starting situation

[suemw]

Westerbek diesel 15 kw suddenly started hunting and losing power. Complete shutdown within minutes. Engine would turn over but would not start. We changed fuel stop solenoid, fuel filter and bled the system. Now when starting; depressing pre-heat switch, then start switch, the engine starts...BUT as soon as the start switch is released the engine immediately shuts down. The preheat switch is still being held on. The oil pressure reaches 50 when the engine starts.
All typical troubleshooting ideas have been tried, including replacing the relay in the box, bypassing oil pressure switch, exhaust high temp shutoff, water temp shut off, by passed 20amp breaker.
Any help would be very welcome.

[four winds]

Did you use a new Westerbeke brand relay for the preheat?

It's a common design used on Fords, Jeeps, etc. But the internal wiring in the relay varies with application. If you used one of these it might not function the same.

Sounds like you are familiar with the elaborate interconnected nature of powering the various bits on this engine. So I can't add anything that will help there.

My friend's Westy 46 (same engine, I think) was doing incomprehensible things I couldn't figure out until finding the correct wiring diagram.

[suemw]

Thank you Four Winds for the quick reply. Yes we did use the westerbek relay. And we do have the wiring diagram. We didn’t use a westerbek fuel stop solenoid but fuel doesn’t seem to be the issue.

[OldGreyB]

Originally Posted by suemw

Thank you Four Winds for the quick reply. Yes we did use the westerbek relay. And we do have the wiring diagram. We didn’t use a westerbek fuel stop solenoid but fuel doesn’t seem to be the issue.

One thought:
1) One of the Westerbek wiring diagrams shows the Fuel Run Solenoid on the rear of the governer with 3 wires,
1 is ground , 1 that is "pull" coil that is downstream of the Starter contact - so will be only energised then the starter relay is energised and stater running, and 1 a "Hold" coil that keeps the solenoid pulled in when the engine is running. So if you have that style, the fuel run solenoid is engerised when your starter is engaged, but if the "hold" wire is not energised when the starter is disengaged, so governer is released. If yours is like that, check power is on the "hold" terminals after the starter disengages.

[Bean Counter]

Does it have a raw water pressure switch?

[suemw]

Old GreyB Just to be sure...the fuel run solenoid you are asking about is the same as fuel stop solenoid that we’ve changed? I’ll take another look at my wiring diagram.

[suemw]

Bean Counter we cool with antifreeze. We have a high temperature switch for the coolant and a high exhaust temperature switch.

[OldGreyB]

Originally Posted by suemw

Old GreyB Just to be sure...the fuel run solenoid you are asking about is the same as fuel stop solenoid that we’ve changed? I’ll take another look at my wiring diagram.

Suemw, I am not sure which exact model you have, if it is basic then then manual calls it the fuel run solenoid, on page 34, 51. The wiring as mentioned in my post is shown on Page 58,

However there appears to be an optional electronic governor version to , which make things a bit more complex as it also has a magnetic speed pickup back to the that governs the fuel delivery . Page 89,90,91
However once again, check the voltages on this when cranking and then when trying to run.

Note I am not familiar with the Westerbeke model, but looked at the manual as you had appeared to have had a good go before posting in frustration.

https://www.westerbeke.com/technical...5100_rev_2.pdf

[four winds]

I believe the 15kw generator is the same engine as the Westerbeke 46.

It's usually called a stop solenoid, but on this engine run solenoid is the correct name. When power is applied it retracts the plunger and fuel is allowed to flow. Power remains on the solenoid all the time the engine is running. Unlike a stop (shut down) solenoid that when engaged temporarily blocks flow until the engines stops, like a fuel stop cable.

I have both manuals so I could look at the gen's diagram, but the 46 has only one wire to the fuel solenoid, 12v to allow flow.

A couple months ago while puzzling over my friends issues, I started a thread here for help. Never got a response from anyone, which was unusual I thought. Then I found the correct diagram in a different engine manual and things worked out. The 46 manual merely hinted at the new way the engines were wired. (8 wire verses 12 wire if you're familiar)

Reason I didn't try to help the OP further is because it seems the starter is engaged with the key switch and not a start button like the 46. Where the key is one position, and sends power to the preheat button and from there to the start button. So the preheat fires the glow plugs and enables the start button. The preheat relay enables the fuel pump and fuel solenoid as long as it's pressed.

Since the OP was still holding the preheat when the engine died after releasing the key the gen is wired differently. Probably gets power to the pump and solenoid from the starter solenoid during starting and from the oil switch after it is running.

Btw, it may also pass this running state voltage via the wiring to the alternator field wire.

I know, it sounds crazy. But all this is what they did to have auto shutdown with oil pressure loss.

[Pitchondesign]

I have the same generator. Although I haven't had this issue, I have had others. So, some thoughts. The electronic governor and speed sensor, if it fails, will slow the engine to idle, but not stop it, so that is probably is not your issue. I did have a situation where the generator would shutdown shortly after starting. It turned out to be wiring. In my case, an insulated wire was touching a lug on the 10 amp breaker. Since the wire was insulated, I didn't pay much attention. When I moved the wire away, the problem was solved. I examined the insulated wire carefully, and could not find any evidence of a breakdown or rub through of the insulation. In my case, when the problem evidenced itself, the panel voltmeter showed less than 9 volts when it should be 13 to 14. It was a simple fix, but very hard to find. Good luck. I struggled with my fix.

[suemw]

Old GreyB. Our model is slightly different than those you reference. Ours is 15kw BTDA with electronic governing. As mentioned we changed the fuel solenoid early on in the trouble shooting process. Our service manual refers to the fuel solenoid a “fuel shut off solenoid”. Ours has a single wire. Also, mentioned is that we were unable to track down the westerbeke replacement (024338) and purchased one online that looks identical. I’m second guessing myself here. But we just disconnected the single wire while trying to start the engine and it turns over but will not start. We reconnected and the engine starts but stops when the starter switch is released. Am I correct in thinking that the solenoid is working just fine?

[Pitchondesign]

The symptoms you describe could be caused by a failure of the emergency stop switch located on the control box atop the generator. Mine failed and immediately stopped in engine. Open up the control box and check voltages at the switch and the terminal board next to the switch. I believe the preheat and start momentary override the emergency stop switch.

[suemw]

Pitchondesign we’ve turned off that switch and tried starting and had nothing. We assumed that proved the switch is working properly. I suppose we could try bypassing the switch. Will check for voltage too.

[suemw]

FourWinds I am not following your recommendation here.

[suemw]

Quick update.
Mechanic onboard for a few hours and as stumped as we have been. He went straight to Thinking it’s a fuel problem. He opened up the actuator, along with the preheat switch and engine still shutdown as soon as starter switch was released. Apparently that suggests there is a problem in the high pressure fuel pump. He is removing it to sent out to be tested. So much for departing for the Caribbean anytime soon. Thanks for all the great advice and suggestions.