7.6BTD blowing 8A fuse

[dtfeld]

I ran the generator all day on the 4th, no problems. Tried to start it yesterday, and I could hear the gen battery solenoid engage, but I did not get a green light on the start switch on the main cabin panel. No pre heat, no start.

Troubleshooting this morning, and I found the 8 amp fuse on the generator control box blown. Replaced and blown again. Oil pressure switch, 20A circuit breaker and K2 relay are the culprits according to the troubleshooting guide. Am I on the right track? Seems odd.

I have good voltage 13.5v, 20 A circuit breaker seems fine.

 

[dtfeld]

Turns out, the coolant temperature switch failed to ground. Bypassed the switch (it’s NC) and she is back to running.

 

[ttmott]

David - for future help attached is a complete electrical schematic for your Westerbeke. I drew this up (due to lack of SR drawing detail) when I had the 400DA.

 

[dtfeld]

Thanks Tom.

I had the schematic on board but my first thought was a faulty fuel pump as I just replaced it, and though that might be the issue, but I disconnected it and nothing changed , so eliminated that.

My dock neighbor is a retired railroad electrician, worked on diesel locomotives, basically big diesel generators. We looked at the schematic and he suggested the temp switch. Sure enough, it was grounded. I did not know they could fail in that manner.

Part ordered.

 

[dtfeld]

Tom you do good work!!

Unfortunately, I'm back to square one...see my next post...

7.6BTD blowing 8A fuse Part 2

 

[ande1416]

Hello -

My 4.5 gen was running fine but I noticed it was not pumping water well, figured it was a failing impeller but turned out to be the water pump bracket broke. I replaced it, unfortunately with the same bolts that worked loose and caused an overheat shutdown.

Now I can start the gen from the unit itself, but as soon as I release the switches it shuts down. Replaced the sensor for water temp, and exhaust temp as both seem not to test to spec. Jumped oil pressure without any change.

Thoughts and next steps? Just got the boat a month ago. Apparently last year the prior owner replaced the over speed circuit board. Any thoughts and help appreciated.

 

[dtfeld]

Hello -

My 4.5 gen was running fine but I noticed it was not pumping water well, figured it was a failing impeller but turned out to be the water pump bracket broke. I replaced it, unfortunately with the same bolts that worked loose and caused an overheat shutdown.

Now I can start the gen from the unit itself, but as soon as I release the switches it shuts down. Replaced the sensor for water temp, and exhaust temp as both seem not to test to spec. Jumped oil pressure without any change.

Thoughts and next steps? Just got the boat a month ago. Apparently last year the prior owner replaced the over speed circuit board. Any thoughts and help appreciated.

That sounds like a problem with one of the temp, or over speed sensors. Your going to have to go through a similar procedure looking for faulty sensors or wiring, but it looks like yours is a gas version, so you also have an ignition system and possibly other sensors/boards not found on a diesel genset.

Get the manuals for you specific model from Westerbeke.com and there should be a schematic in the back and a troubleshooting guide.

I would also suggest reposting this in the gas engine/transmission/drive or general maintenance forum with the specific model #. You'll get responses from people that have experience with that specific generator, and possibly better advice.