Posted by saumon on 08/02/14 - 8:34 AM
#2
alan c wrote:
2002 dauntless w 90 hp mercury - running great then started beeping from console - beeping would stop when at very low idle speed - fuel filter? Water? any recommendations would be most appreciated!
Is your engine a 2-stroke or 4-stroke? What kind of alarm: continuous or intermitent "beep"? The owners manual of your engine should tell you what it mean.
Typically, on Merc 2-stroke oïl-injected, intermitent "beep" mean low-oil and steady "beep" overheating. On 4-stroke, steady beep still indicate overheating.
Posted by saumon on 08/02/14 - 7:19 PM
#6
It depends if you have some basics mechanical skills.
Outboards are water-cooled; water enter through the intake, or pick-up, is forced up by the centrifugal force of the impeller, a kind of 4" rubber prop that sit around the driveshaft, and pushed through a tube up to the block and around it via little passages, before exiting via the water outlet, or tell-tale.
From your description (work fine at idle but overheat if your give some throttle), it seems to have a problem with the water supply, somewhere in the cooling system, so it could be 4 things: 1- clogged intake, 2- bad impeller, 3- blocked passages, 4- blocked tell-tale.
http://www.google.ca/url?sa=i&rct=j&q...7061343774
On the Merc, there's no screen on the intake (the series of holes on the gearcase, in front of the prop) so they rarely became clogged. As for the impeller, to replace it is part of the regular maintenance. Some says to change it every year and other will tell you they've done 20 years with the same impeller. Because rubber harden over time and become brittle, 3 year is a sensible schedule to replace it. Having had a similar Merc 3-cylinder, I bet you may simply have a clogged tell-tale. It's a small plastic fitting with a barbed end and a tiny hole on the other side, located on the lower cowling that get easily clogged and I've done that kind of "repair" many times, on the water. Remove the cowling, cut the tie-wrap at the end of the hose and pull it, while holding the fitting from the exterior, then remove and blow through it. Because there's no screen on the intake, all the debris (algae, sand, etc.) flow through the system and get stuck there, at the outlet, thus restricting the water flow.
The tell-tale fitting is #10 on that diagram:
http://www.crowleymarine.com/mercury-...374_20.cfm
So, as an easy check, first look at that tell-tale fitting then, if it isn't clogged, your impeller may be due.
For the impeller change, it isn't THAT hard. You first remove the lower unit (there's a fifth bolt hidden under the tab anode) from the mid-section (on these engines, there's no need to disconnect the shift rod, it's splined) then unbolt and lift-off the water pump housing. You then remove the impeller, paying attention not to loose the key, and put the new one on the drive shaft, securing it with the key. Now, to put back the housing, "grease" the interior with liquid soap and push it against the impeller while rotating the driveshaft clockwise (when viewed from the top) then fasten the housing. Place everything in neutral (the throttle handle AND the gearcase, by rotating the shift rod with a pair of Vise-Grip, until the prop spin freely in either directions) then (this is the trickiest part!) line up everything (shift rod, drive shaft and water tube) while putting the gearcase and mid-section together. You may need several attempts at wiggling before everything fall into place and that's where a second pair of hands could be handy. It could also be a good investment to hire a mechanic or somebody who done it before to learn...
Sorry if it wasn't clear but English isn't my first language...
Here's a few videos showing it:
http://www.youtube.com/watch?v=NtJXv2...tJXv2GqhYM
http://www.youtube.com/watch?v=BiQNhF...iQNhFYFvdQ
Edited by saumon on 08/02/14 - 8:28 PM
Posted by alan c on 08/03/14 - 2:38 PM
#7
Thank you very much for taking the time to reply - the video's were very helpful. Seems like pulling the boat out is the only way to deal with this. Thank you again.
saumon wrote:
It depends if you have some basics mechanical skills.
Outboards are water-cooled; water enter through the intake, or pick-up, is forced up by the centrifugal force of the impeller, a kind of 4" rubber prop that sit around the driveshaft, and pushed through a tube up to the block and around it via little passages, before exiting via the water outlet, or tell-tale.
From your description (work fine at idle but overheat if your give some throttle), it seems to have a problem with the water supply, somewhere in the cooling system, so it could be 4 things: 1- clogged intake, 2- bad impeller, 3- blocked passages, 4- blocked tell-tale.
http://www.google.ca/url?sa=i&rct=j&q...7061343774
On the Merc, there's no screen on the intake (the series of holes on the gearcase, in front of the prop) so they rarely became clogged. As for the impeller, to replace it is part of the regular maintenance. Some says to change it every year and other will tell you they've done 20 years with the same impeller. Because rubber harden over time and become brittle, 3 year is a sensible schedule to replace it. Having had a similar Merc 3-cylinder, I bet you may simply have a clogged tell-tale. It's a small plastic fitting with a barbed end and a tiny hole on the other side, located on the lower cowling that get easily clogged and I've done that kind of "repair" many times, on the water. Remove the cowling, cut the tie-wrap at the end of the hose and pull it, while holding the fitting from the exterior, then remove and blow through it. Because there's no screen on the intake, all the debris (algae, sand, etc.) flow through the system and get stuck there, at the outlet, thus restricting the water flow.
The tell-tale fitting is #10 on that diagram:
http://www.crowleymarine.com/mercury-...374_20.cfm
So, as an easy check, first look at that tell-tale fitting then, if it isn't clogged, your impeller may be due.
For the impeller change, it isn't THAT hard. You first remove the lower unit (there's a fifth bolt hidden under the tab anode) from the mid-section (on these engines, there's no need to disconnect the shift rod, it's splined) then unbolt and lift-off the water pump housing. You then remove the impeller, paying attention not to loose the key, and put the new one on the drive shaft, securing it with the key. Now, to put back the housing, "grease" the interior with liquid soap and push it against the impeller while rotating the driveshaft clockwise (when viewed from the top) then fasten the housing. Place everything in neutral (the throttle handle AND the gearcase, by rotating the shift rod with a pair of Vise-Grip, until the prop spin freely in either directions) then (this is the trickiest part!) line up everything (shift rod, drive shaft and water tube) while putting the gearcase and mid-section together. You may need several attempts at wiggling before everything fall into place and that's where a second pair of hands could be handy. It could also be a good investment to hire a mechanic or somebody who done it before to learn...
Sorry if it wasn't clear but English isn't my first language...
Here's a few videos showing it:
http://www.youtube.com/watch?v=NtJXv2...tJXv2GqhYM
http://www.youtube.com/watch?v=BiQNhF...iQNhFYFvdQ