Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 17-08-2019, 20:29   #1
Registered User

Join Date: Jun 2015
Location: Sydney Australia
Boat: Lagoon 450
Posts: 70
Yanmar engine starts but power buzzer does not turn off/ no tacho

I can start my Yanmar engine as usual but the power buzzer does not turn off and the tacho does not display revs. If I turn off the power switch the engine continues to run and the buzzer stops but of course the instrument panel is off. I can then turn the power switch back on and press the stop switch and the engine stops as usual, and then I turn off the power switch to stop the buzzer.

Any advice on how to diagnose /fix? Am i causing any damage by running the engine with the instrument panel turned off?

Thanks!
gstent is offline   Reply With Quote
Old 17-08-2019, 21:02   #2
Registered User

Join Date: Feb 2016
Location: So Cal
Boat: Lancer 44 Motor Sailer
Posts: 548
Re: Yanmar engine starts but power buzzer does not turn off/ no tacho

Just a hunch, I would look at alternator output.
Diesel Bill is offline   Reply With Quote
Old 17-08-2019, 21:14   #3
Registered User

Join Date: Jun 2015
Location: Sydney Australia
Boat: Lagoon 450
Posts: 70
Re: Yanmar engine starts but power buzzer does not turn off/ no tacho

Quote:
Originally Posted by Diesel Bill View Post
Just a hunch, I would look at alternator output.
Yep ... on my way back to the anchorage to check fan belt etc cheers
gstent is offline   Reply With Quote
Old 18-08-2019, 00:06   #4
Registered User
 
NYSail's Avatar

Join Date: Jan 2012
Location: Long Island, New York
Boat: Beneteau 423 43 feet
Posts: 620
Re: Yanmar engine starts but power buzzer does not turn off/ no tacho

I thought you weren’t suppose to turn the switch off until you stopped the engine. .... causes problems.
NYSail is offline   Reply With Quote
Old 18-08-2019, 00:35   #5
Certifiable Refitter/Senior Wannbe
 
Wotname's Avatar

Join Date: Jan 2008
Location: South of 43 S, Australia
Boat: C.L.O.D.
Posts: 11,452
Re: Yanmar engine starts but power buzzer does not turn off/ no tacho

Presumably the idiot lights are OFF (???) i.e. you don't have a low oil pressure or high water temperature alarm or charge light.

What model Yanmar?
Is this happening on one engine only?

Running with the power switch OFF is not going to cause any immediate damage to the engine except that you have shut down the engine alarms which sort of means you are running blind.
__________________
All men dream: but not equally. Those who dream by night in the dusty recesses of their minds wake in the day to find it was vanity: but the dreamers of the day are dangereous men, for they may act their dreams with open eyes, to make it possible. T.E. Lawrence
Wotname is offline   Reply With Quote
Old 18-08-2019, 03:40   #6
Registered User

Join Date: Jun 2015
Location: Sydney Australia
Boat: Lagoon 450
Posts: 70
Re: Yanmar engine starts but power buzzer does not turn off/ no tacho

Quote:
Originally Posted by Wotname View Post
Presumably the idiot lights are OFF (???) i.e. you don't have a low oil pressure or high water temperature alarm or charge light.

What model Yanmar?
Is this happening on one engine only?

Running with the power switch OFF is not going to cause any immediate damage to the engine except that you have shut down the engine alarms which sort of means you are running blind.
Yes warning lights are off (and never came on apart from usual start up procedure)
4JH5E
Only on one engine - other fine (Lagoon450)

Thanks for the info
gstent is offline   Reply With Quote
Old 18-08-2019, 08:57   #7
Registered User

Join Date: Mar 2012
Location: San Diego Ca
Boat: Hunter, 420 Passage
Posts: 64
Re: Yanmar engine starts but power buzzer does not turn off/ no tacho

Check all leads to ignition switch coming in and going out.
Carver Power is offline   Reply With Quote
Old 18-08-2019, 08:58   #8
Registered User

Join Date: Jul 2015
Location: West Palm Beach, FL
Posts: 99
Re: Yanmar engine starts but power buzzer does not turn off/ no tacho

I would have immediately checked oil and coolant levels. If they are both fine, you are in a much less worrisome position about the buzzer.
sheldon957 is offline   Reply With Quote
Old 18-08-2019, 09:03   #9
Registered User
 
Cheechako's Avatar

Join Date: Aug 2006
Location: Skagit City, WA
Posts: 22,867
Re: Yanmar engine starts but power buzzer does not turn off/ no tacho

Quote:
Originally Posted by NYSail View Post
I thought you weren’t suppose to turn the switch off until you stopped the engine. .... causes problems.
Depending on how the boat is set up, yes , it can blow the alternator.
__________________
"I spent most of my money on Booze, Broads and Boats. The rest I wasted" - Elmore Leonard











Cheechako is offline   Reply With Quote
Old 18-08-2019, 09:05   #10
Registered User

Join Date: Jan 2015
Boat: Lagoon 450 F
Posts: 131
Re: Yanmar engine starts but power buzzer does not turn off/ no tacho

Doesn't the battery light come on? It should light up at every start? If the buzzer stops when you accelerate (even when idling), then the battery may be empty or broken, or the wire from the alternator does not tell the panel that the starter battery is charging, or the Batterie does not tell the alternator.

Here was another thread with a similar problem: the fan of the engine ventilation led to the failure of the fuse between alternator and battery switch or something similar.
Ulstue is offline   Reply With Quote
Old 18-08-2019, 09:33   #11
Registered User

Join Date: Feb 2015
Location: Somewhere warm
Boat: Morgan 462
Posts: 1,232
Re: Yanmar engine starts but power buzzer does not turn off/ no tacho

Quote:
Originally Posted by Cheechako View Post
Depending on how the boat is set up, yes , it can blow the alternator.
I am not sure you are correct. Turning off ignition switch while engine is running will remove field current to the alternator, if an external regulator is used. External regulator gets its power from ignition switch. Removing field excitation should reduce alternator output to nearly zero. If internal regulator there is probably no change in alternator conditions.

Did I miss something?

Of course this assumes a direct connection from alternator to at least one battery at all times. Never heard of a setup where there was a relay in that connection that had to be powered from the ignition switch, but suppose it is possible as a protective measure.

BTW ignition switch usually powers the hour meter also, so if you run engine very long without proper ignition circuit function or leave a functioning ignition on when engine not running your hour meter will be wrong.
waterman46 is offline   Reply With Quote
Old 18-08-2019, 10:01   #12
Registered User

Join Date: Dec 2012
Boat: Jeanneau SO45.2
Posts: 237
Re: Yanmar engine starts but power buzzer does not turn off/ no tacho

What “power buzzer”? My Yanmar has a warning buzzer for any alarm light, normally the low oil pressure alarm sounds when first started until pressure comes up, usually in a few seconds. Could also be due to the (no) charge warning light. If yours keeps sounding, you need to figure out why and fix that.
Redline452 is offline   Reply With Quote
Old 18-08-2019, 11:04   #13
Registered User

Join Date: Mar 2015
Location: Dundee Scotland, Currently cruising the Baltic Sea
Boat: Vancouver 32
Posts: 28
Re: Yanmar engine starts but power buzzer does not turn off/ no tacho

Hi, its not a “power buzzer” its a low oil pressure alarm and could be very serious to the health of the engine. You may have noticed that when the engine is cold and you stop it (with the ignition still on) it takes a few seconds until the buzzer comes on again? This is because the oil is cold and thicker.

Do not continue to run the engine until you have at the very least checked the oil level on the dip stick. If there is plenty of oil, it could be an oil filter problem, change the filter if you have one.
Best case scenario is it could be a faulty oil pressure switch. (Or even the wire for it has come of and is shorting to earth!) You need to get this properly diagnosed BEFORE running the engine again, worst case is serious mechanical damage to the engine.

And NEVER turn of the ignition switch when the engine is running, (unless it is designed with an electric engine stop and specifically tells you in the instructions to do so) it could (and May already have) blown the alternator diodes (which may be the reason the tacho is not working!
Sorry for the bad news.
Colin
ColinIOM is offline   Reply With Quote
Old 18-08-2019, 13:18   #14
Registered User

Join Date: Jan 2014
Location: Ft. Lauderdale
Boat: Watkins 29
Posts: 374
Re: Yanmar engine starts but power buzzer does not turn off/ no tacho

What model Yanmar? 2GM Tamara get the tach signal from a sensor on the bellhousing that counts teeth on the flywheel!

My guess is that if you indeed have a 2GM engine, the tach and oil pressure warning are loosing electrical connection at one of the connector plugs in the engine harness.

Suggest you trace the wires from the oil pressure sensor into tge harness, and disconnect the connector plugs and clean the connections carefully. Don't worry about the connection, they can only go one way!
dennismenace111 is offline   Reply With Quote
Old 18-08-2019, 15:52   #15
Registered User

Join Date: Sep 2007
Location: Queensland, Australia
Boat: None at present--between vessels. Ex Piver Loadstar 12.5 metres
Posts: 1,285
Re: Yanmar engine starts but power buzzer does not turn off/ no tacho

Your alternator voltage regulator may be kaput, or the brushes on the slip rings in the alternator worn out.

Annoying--but not a biggie--less than a hundred bucks--
Mike Banks is offline   Reply With Quote
Reply

Tags
engine, yanmar

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Yanmar 20GM20 starts but wont run mowerandy Engines and Propulsion Systems 24 22-01-2018 07:41
4-108 Starts fine cold, but not when warm rkurtz115 Engines and Propulsion Systems 2 14-10-2017 16:05
3YM30 coolant buzzer going off, but engine not overheating jbinbi Engines and Propulsion Systems 21 09-07-2017 17:57
Engine starts but won't keep running mikefossl Engines and Propulsion Systems 12 31-10-2013 18:47
YANMAR TACHO (1GM) bill good Engines and Propulsion Systems 0 06-05-2009 17:39

Advertise Here


All times are GMT -7. The time now is 07:19.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.