Westerbeke Generator Stops???

The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.
See posts with no answers
Knot-Enuff

Knot-Enuff

Veteran Member
Joined
Jan 23, 2013
Messages
30
Location
USA
Vessel Name
Knot Enuff
Vessel Make
Atlantic 47'
My boat is equipted with a Westerbeke Generator, Model #WMD-12, 12.5KVA. It has run fine since I've owned the boat. Last week I went to take the boat out and started the generator first, as I always do. I held down the preheat switch for a few seconds and while holding it down, I pressed the start switch. She started right up. When I released the preheat switch, it immediately stopped. I followed the same process and again, she started right up, ran smooth but as soon as I released the preheat switch, she stopped. I did not want to hold the preheat switch too long but each time the motor started up and ran fine.

Any suggestions as to where I should start looking? I thought about the shutoff switch, but I believe that shuts off the fuel. This seams as it could be electrical. Thanks for any suggestions.
 
Knot-Enuff said:
My boat is equipted with a Westerbeke Generator, Model #WMD-12, 12.5KVA. It has run fine since I've owned the boat. Last week I went to take the boat out and started the generator first, as I always do. I held down the preheat switch for a few seconds and while holding it down, I pressed the start switch. She started right up. When I released the preheat switch, it immediately stopped. I followed the same process and again, she started right up, ran smooth but as soon as I released the preheat switch, she stopped. I did not want to hold the preheat switch too long but each time the motor started up and ran fine.

Any suggestions as to where I should start looking? I thought about the shutoff switch, but I believe that shuts off the fuel. This seams as it could be electrical. Thanks for any suggestions.
Click to expand...

The preheat switch when starting by passes the safety circuits, perhaps one of those switches is bad or has a bad connection. Good luck
 
On our WB12.5, it is necessary to continue holding down the start button (not the preheat) for a few seconds after the engine fires. You might try this.
 
Check the Oilpressswitch , take one bridge on this switch for proof.
You have change the Oil now?
____________
norbert
 
Usually the preheat button is also the low oil pressure shutdown override.

Was the oil pressure up to 20 or so when letting go? If not... hold longer...if it's up I would look at removing a wire from the low oil pressue sensor or where one of those wires goes to the fuel cutoff.

Westerbeake has a pretty good troubleshooting section online if I remember. Take a look there if you don't have a manual handy.
 
On my Westerbeke the prehead must be held down for 3 or 4 seconds after the start, as it bypasses the low oil pressure shutdown.
 
My schematic shows that the pre-heat relay provides power to the fuel lift pump and fuel solenoid during starting. Once the oil pressure is up to par it provides power to the lift pump and fuel solenoid allowing the engine to run with the pre-heat released.

Your description seems to indicate that the oil pressure switch is not doing its job.
 
obthomas said:
My schematic shows that the pre-heat relay provides power to the fuel lift pump and fuel solenoid during starting. Once the oil pressure is up to par it provides power to the lift pump and fuel solenoid allowing the engine to run with the pre-heat released.

Your description seems to indicate that the oil pressure switch is not doing its job.
Click to expand...

Your right, perhaps the elektric contact from Relais and oil pressure switch are wrong.
___________
Norbert
 
On my 8kw Westerbeke there are three safety switches. Oil pressure, water temperature and exhaust elbow temperature. If anyone of these has failed you would have the condition you describe. As others have explained the preheat switch overrides these safety switches.
 
Bay Pelican said:
On my 8kw Westerbeke there are three safety switches. Oil pressure, water temperature and exhaust elbow temperature. If anyone of these has failed you would have the condition you describe. As others have explained the preheat switch overrides these safety switches.
Click to expand...

Mine too. I usually hold down pre-heat a few seconds longer than start and I check to see that the oil pressure has come up.

Last week, I did have a condition in which the Gen would start, but run for only a minute or so, with no power, before it died. Replacing the racor solved that problem.

Good luck

Richard
 
Normaly stops the gen when the oilpressure are down or the water temp are high. Proof this two swiches with bridge ore cut the bridge. I dont no in this moment are two contacts are normaly open or closed and open when the temp are high or the Oilpressure down.
______________
Norbert
 
I have one WB 15 KW and two WB 8 KW an Board. Last year i had the same problem, now i refresh my memory. The probleme are one from the little relais in the startbox are bad. I dont no whitch relais, chance both and i think thats is the Problem.
_________
Norbert
 
Had a similar situation crop up with our NextGen 3500kW when we started it up for the first time earlier this season. As soon as I let go the start switch, it stopped running. Turned out to be a sticky starter solenoid. I manually played with it, pushing it in and out, and it has started fine every time since.
 
On my 5k northern lights genny, with westerbeak engine, I had the same problem. I removed the grey (?) wire and it ran fine. Traced it to a faulty exhaust temperature sensor.
 
Actually if water temperature or exhaust elbow temperature sensors were the problem the generator would not start, because the pre-heat does not bypass them. Knot-Enoughs problem is probably with the oil pressure switch.
 
Obthomas: my symptoms were exactly as the op's. it would only stay running with the override switch held up. When I replaced the temp switch, problem solved.
 
Does anyone know how to test the three safety switches on a Westerbeke. Can you bypass them by jumping them?

Marty
 
Bay Pelican said:
Does anyone know how to test the three safety switches on a Westerbeke. Can you bypass them by jumping them?

Marty
Click to expand...

Oil pressure ....I think yes after looking at the wiring diagrams but the others may be resistance and just cant jump them...but I'm not sure as the manuals I looked at had no info on them.

Best to find the specs on the sensors or call.
 
The temperature switches provide grounds to the stop relay. To test the temperature switches simply disconnect them one at a time and see if the generator starts and runs.
 
Thanks to all. I will be at the boat this weekend and start checking. I appreciate all of the direction, great group on this site!
 
Thanks, testing the switches may be useful some day.

Marty
 
Had to chuckle. Just got back from desolation sound and had exactly the same symptoms - changed fuel filters, chased wiring,and in the end it was as simple as the momentary toggle stop switch wasn't so momentary! Making sure the stop switch was firmly back off solved the 'problem'. I'll have to change the switch another day, but until then I am good to go.
 
You must log in or register to reply here.

Similar threads

A
Westerbeke not starting
Replies
16
Views
2K
High Wire
High Wire
HeadedToTexas
Controls to keep, move, or remove
Replies
3
Views
531
HeadedToTexas
HeadedToTexas
slowgoesit
Isuzu 4LE2 engine will not stay running.
Replies
7
Views
2K
Portage_Bay
Portage_Bay
Pau Hana
Generator woes- low compression across all cylinders
Replies
23
Views
3K
Symphony
Symphony
P
Sorting through AC electrical system.
Replies
16
Views
880
PierreR
P

Latest posts

Back
Top Bottom