|
|
19-07-2017, 11:46
|
#1
|
Registered User
Join Date: Mar 2010
Location: Faro - Portugal
Boat: Sessa Oyster18 Mercury 90hp Carb
Posts: 77
|
Mercury - I'm already desperate
Hello,
I need your help, and I can not understand the cause of the malfunction.
I have a Mercury 90hp 3cyl two strokes, the alarm rings continue after 5 minutes in normal progress. The mechanical changed the new water pump (impeller) new thermostat, new temperature sensor.
Any of the sensors were changed as we thought it might be defective, but it continued, we reinstalled the new sensors. We've been in the sea without thermostat and without temperature sensor, the whistle continues.
I do not know what to do, thank you for help, please.
The motor does not enter safe mode. Always has power.
Sorry my bad inglish, google translator.
__________________
Best regards, Algarve...
|
|
|
19-07-2017, 12:01
|
#2
|
Registered User
Join Date: Apr 2017
Posts: 56
|
Re: Mercury - I'm already desperate
You should be able to see and check water flow from the back of the engine.
Have you checked the oil level sensor? Perhaps a loose wire?
I had a 75 growing up and the only time the alarm went off was because of restricted water flow from grass clogging the intake.
Good luck. Trouble shooting alarms and issues can be maddening.
|
|
|
19-07-2017, 12:14
|
#3
|
Registered User
Join Date: Mar 2010
Location: Faro - Portugal
Boat: Sessa Oyster18 Mercury 90hp Carb
Posts: 77
|
Re: Mercury - I'm already desperate
Quote:
Originally Posted by spearfish3
You should be able to see and check water flow from the back of the engine.
Have you checked the oil level sensor? Perhaps a loose wire?
I had a 75 growing up and the only time the alarm went off was because of restricted water flow from grass clogging the intake.
Good luck. Trouble shooting alarms and issues can be maddening.
|
Thanks for the answer. The flow of water is constant and cold, new impeller.
Full oil tank, if it were oil the alarm was intermittent.
__________________
Best regards, Algarve...
|
|
|
19-07-2017, 12:25
|
#4
|
Moderator
Join Date: Aug 2009
Location: Solent, England
Boat: Moody 31
Posts: 18,398
|
Re: Mercury - I'm already desperate
I would buy one of those temperature guns and measure lots of bits of the engine after a good run.
Is there a chance that the alarm is the result of a damaged wire and nothing to do with the engine overheating at all?
Have you done a compression test btw? in case you have a cracked block or head.
Pete
|
|
|
19-07-2017, 12:40
|
#5
|
Registered User
Join Date: Mar 2010
Location: Faro - Portugal
Boat: Sessa Oyster18 Mercury 90hp Carb
Posts: 77
|
Re: Mercury - I'm already desperate
Quote:
Originally Posted by Pete7
I would buy one of those temperature guns and measure lots of bits of the engine after a good run.
Is there a chance that the alarm is the result of a damaged wire and nothing to do with the engine overheating at all?
Have you done a compression test btw? in case you have a cracked block or head.
Pete
|
Thanks for the answer.
I'm intrigued by one thing. I replaced the starter selenoid exactly as it was connected the faulty, I was careful to take pictures so as not to fool me with the wires.
Can it have any relevance?
__________________
Best regards, Algarve...
|
|
|
19-07-2017, 12:40
|
#6
|
Registered User
Join Date: Nov 2016
Posts: 374
|
Re: Mercury - I'm already desperate
Advise I am about to give isn't good. But, if it were me I would cut power to the alarm. Screw doing a bunch of stuff and spending all that money. If compression is good. Water is flowing. Good to go in my book.
Now keep the gauges, they are important. Just do away with the faulty alarm.
That's just me.
|
|
|
19-07-2017, 13:46
|
#7
|
Senior Cruiser
Join Date: May 2013
Location: Oregon to Alaska
Boat: Wheeler Shipyard 83' ex USCG
Posts: 3,494
|
Re: Mercury - I'm already desperate
The alarm is probably turned on by a relay connected to both power and to the sensors. Over time, the contact points tend to burn from the transfer of power and can either fail to connect or weld together and never shut off the alarm.
You're have to carefully trace all the alarm/sensor wiring with engine off and later with the engine on. Find where power comes from to energize the alarm and what exactly turns it off.
|
|
|
19-07-2017, 14:06
|
#8
|
Registered User
Join Date: Mar 2007
Location: Saint Thomas, USVI
Boat: Fountaine Pajot Lipari 41
Posts: 307
|
Re: Mercury - I'm already desperate
Quote:
Originally Posted by hobopacket
Advise I am about to give isn't good. But, if it were me I would cut power to the alarm. Screw doing a bunch of stuff and spending all that money. If compression is good. Water is flowing. Good to go in my book.
Now keep the gauges, they are important. Just do away with the faulty alarm.
That's just me.
|
Do not do this under any circumstance. The alarm could be oil related. This is an oil injected two stroke? Make sure there is positive pressure on the oil system. Also check the sensor/float in the oil tank. I had one fail on a larger Mercury that gave a false alarm. If it stops oiling it will blow up in short order.
Jay
|
|
|
20-07-2017, 04:21
|
#9
|
Registered User
Join Date: Nov 2016
Posts: 374
|
Re: Mercury - I'm already desperate
Does it not tell you which alarm is going off? As in either water or oil?
Yeah I am used to all the old pre mix. I haven't had a two stroke in quite a while.
|
|
|
20-07-2017, 09:31
|
#10
|
Registered User
Join Date: Nov 2016
Boat: '95 Catalina 30
Posts: 44
|
Re: Mercury - I'm already desperate
Hi Algarve,
You may get better answers/more info (not that any of the responses here have been bad) by posing your question for the folks on the "Powered Boats" section of the forum. This is the monohull sailboat forum; mostly diesel powered sailboats boaters...
Good luck.
Jim
|
|
|
20-07-2017, 10:09
|
#11
|
Registered User
Join Date: Dec 2008
Location: SC
Boat: None,build the one shown of glass, had many from 6' to 48'.
Posts: 10,208
|
Re: Mercury - I'm already desperate
Quote:
Originally Posted by Pete7
I would buy one of those temperature guns and measure lots of bits of the engine after a good run.
Is there a chance that the alarm is the result of a damaged wire and nothing to do with the engine overheating at all?
Have you done a compression test btw? in case you have a cracked block or head.
Pete
|
Ditto on it being a wiring problem having nothing to do with the engine.
|
|
|
20-07-2017, 10:36
|
#12
|
Registered User
Join Date: Aug 2010
Location: New Bern
Boat: C & C Landfall 35
Posts: 17
|
Re: Mercury - I'm already desperate
Replace the whistle?
|
|
|
20-07-2017, 11:47
|
#13
|
Registered User
Join Date: Mar 2015
Location: San Francisco Bay area
Boat: Condor Trimaran 30 foot
Posts: 1,501
|
Re: Mercury - I'm already desperate
Have you consulted a Catholic Priest yet? Just joking with you. There are times that engines seem to be "possessed" by demons. Best of luck. I have a 4 hp 2 stroke that is currently "demonic".
|
|
|
20-07-2017, 12:33
|
#14
|
Registered User
Join Date: Sep 2016
Posts: 28
|
Re: Mercury - I'm already desperate
I would make sure the oil reservoir is full, I have a 150 2 stroke and if the reservoir under the coupling is not full the alarm will go off. Also the buzzer has a different sound or flashing of the light. Solid I think is for heat and flashing is oil. could be the other way around.
Good luck
|
|
|
20-07-2017, 13:30
|
#15
|
Registered User
Join Date: Nov 2016
Posts: 374
|
Re: Mercury - I'm already desperate
Quote:
Originally Posted by dan swift
I would make sure the oil reservoir is full, I have a 150 2 stroke and if the reservoir under the coupling is not full the alarm will go off. Also the buzzer has a different sound or flashing of the light. Solid I think is for heat and flashing is oil. could be the other way around.
Good luck
|
If it is a different alarm as stated above that would help determine where to look. Good thinking.
|
|
|
|
|
Thread Tools |
Search this Thread |
|
|
Display Modes |
Rate This Thread |
Linear Mode
|
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
|
Advertise Here
Recent Discussions |
|
|
|
|
|
|
|
|
|
|
|
|
Vendor Spotlight |
|
|
|