Hey Rich in the video you mentioned you had a service manual where can I obtain one of those at I have the same exact motor but don't have a manual for it
I sure could use some advice I have the same motor and the same symptoms as you I would like to know you said it felt like a momentary loss of power. Like hitting a log. Did it ever get worse as time went on like a big down and then full power then bog down.
Hi Brian, the symptom of sudden/momentary drop in power was the first thing I noticed. It happened only above about 30 mph. Below that it ran fine. When it did happen there was the drop in power but the overheating alarm 'chirped'. It never got any worse but I couldn't run at full throttle at all. I replaced the rev limiter and that solved the problem Down the road a couple of seasons the motor was running fine, but if I throttled down it died and was extremely difficult to start, two times. I was on the water, about 4 miles from the dock. I thought I was going to get stuck, but I had a group 27 battery and I was able to crank enough to get it running. The next morning it started immediately. The next trip I went on it wouldn't start at all. I ended up replacing the stator and the motor started up right away. Yay! But when I took it up full throttle it died at 4900 RPM, nose dived, dropped RPMs and went full throttle, nose dived, etc. Below 5000 RPM it ran fine (like with my 4-blade prop). It acted like it was the rev limiter again. I bought another one, same story. I disconnected the rev limiter and have not had a problem since then. If you suspect the rev limiter, disconnect it: On the switch box (power pack), left row, 3rd wire down (on mine) is a black wire with yellow stripe. (This wire comes from the kill switch at the console.) Also on that same post is a black wire. That black wire goes to a junction box between the switch box and rev limiter. If you remove the black wire and tape up the end that removes the rev limiter from the circuit. (If not careful, you could over-rev your engine, particularly when starting.)
Thanks for this Rich, having a similar issue with my Optimax. My situation presents slightly different, so Im wondering if it's the same cause. Again when motor is under load ( 3500 to 4000) RPM, beeping alarm, sudden drop ( 2 0r 300RPM ) in power, followed by engine chirping or cutting in and out like bad fuel). I return to idle, warning signal clears and I take off normally, Problem may or may not do present again. I guess I should do what you did and just pull the negative test againi?
If your alarm is chirping (mine would only chirp, it didn't continue beeping) when the sudden drop occurs, try my suggestion to disconnect the kill switch on the switch box. Then take it to the lake for a day of fishing and see if it happens again. I did that and there was no return of the problem. I replaced the rev limiter and haven't had the problem again. In my search, I found 2 other people with the same issue but different horsepower motors. Something else, take off the rev limiter and inspect the back. My had several cracks in it, quite visible.
I have similar issue not 100% if it’s as you described mine would only get to 3500 which is low couldn’t get on a plane backed off the throttle then got back into and seemed to fix it and since have had it fall on its face then come back to life. I found the alarm module behind my dash someone disconnected it if I reconnect it it’s a constant annoying tone. Was your alarm a momentary chirp when it started becoming a constant issue or was it just momentary chrips
There are 2 alarms: overheating (behind the rev limiter) and low oil. My alarm was an extremely short beep that happened at the same time the engine just blinked out. It felt like I hit something, like a log. It was that short, just a thump. It happened only above 25 mph, never below, never more than a fraction of a second. When I took the rev limiter off it was cracked. I believe it was shorting out through the heat alarm or maybe jumping to that wire and making it beep. I just replaced the rev limiter because there was no other symptom for the alarm. A continuous beep is the overheating alarm. If this has been disconnected then something is definitely wrong. My best guess (consider that I'm an amateur at outboard repair) is that the rev limiter is bad, causing you to fail to get on plane. At low throttle it's getting/sending a false signal and when you go up-throttle you give it more electrical power and it overcomes the problem. A bad rev limiter may have caused the heat sensor to fail, causing the continuous alarm. If it were me, I would remove and inspect both, looking for obvious damage. Since the alarm is continuous now, it's probably bad. (Does it go on as soon as you turn the key?) That's a bad sensor to be disabled. Get your water intake plugged up with weeds and you can burn up your engine. Getting to this area is not easy. If it were me, I'd replace both sensors; overheat and rev limiter. I know this is throwing parts at a problem but sometimes it's the only solution without more knowledge of outboard motors. You can find part numbers at the Mercury online catalog, you need your serial number. www.mercurymarine.com/en/us/parts-and-accessories/parts-catalog
Hey, i have the same outboard. At WOT it kindof sounds like its hitting the rev limiter a little bit. But the tach is only showing around 4800 - 5000 rpm. Any ideas ?
Have you replaced any parts lately? I ask because I just replaced the stator and switch box in mine. The motor is running again but at 5000 RPM it drops out, falters. Below 5000 I can run for miles. I was told it was fuel starvation, but I don't think so. I think it's either the new switch box or the rev limiter You can disable the rev limiter to see if that solves the problem. On the switch box is a terminal with 2 black / with yellow stripe wires. Trace to be sure but on mine the bottom one goes to the limiter, the other to the wiring harness and up to the ignition/kill switch. Remove that bottom wire and tape over the end so it doesn't touch anything. The other wire has the large terminal cover, leave that one connected. Run the boat again and watch your RPMs. Don't exceed 5250. If the motor still falters then it's fuel starved, most likely. Check your fuel line hose/bulb for a disintegrating inner nylon line. Check the fuel filter for small bits of nylon, also the fuel pump. You'll need to clear out/replace the fuel lines completely
@Rich Ward hi thanks for the quick reply. New fuel tank, line, filter, and pump. It wont quite hit 5000 rpm sounds like a very faint hint of rev limiter sound. The maximum RPM is meant to 5250 ? Maybe my tach is off by a few hundred rpm
@@nickt197 You still running the OEM 3-blade Quicksilver Laser II? If you run a 4-blade the RPMs will be lower. That gave me an idea to take my 4-blade with me to the lake for a test using that one. The rev limiter is supposed to be set for 5250 out of the box. I've never gone above that number but the motor wasn't doing anything strange. It's always been at least 5200 even with the boat speed dropped. Now when I reach 5000 the motor just shuts down to below 5000 then jumps back up and falters again, over and over but if I just drop it to below 5000 it runs just fine, 40 mph about. I don't know when you're going back to the lake but I'm going on Wednesday, weather permitting. I've disconnected my rev limiter and I'll see how it behaves. I'll post the results here.
Hi Rich I enjoyed your video I have the exact same motor as u do. My problem is my battery is not charging will running so i changed the voltage regulator rectifier and battery will charge now but the voltage is all over the place and the motor is running poorly. I am thinking stator now, wonder if u ever changed yours?
UA-cam doesn't always notify me so sorry this is so late of a reply. I didn't change the stator, the limiter was the problem. My engine starts and runs well, just can't get that last 5 MPH that it used to give me. It tops out at 47 now and even not always that. The voltage will vary as you throttle up and down but should remain steady at the same speed and not over about 14.1 volts. That's the job of the voltage regulator. At 15+ volts your wires on the regulator will start melting; mine did. I don't have the tools to replace the stator and have never pulled the flywheel. It's out of my league.
Thanks for a good video. Can I by disconnecting some wires in your video, ignore rev limiter . To cut out the black negativ wire at left side row will disconnect the function of built in rev limiter ? Right? No problems with that?___________ And do you have some clue of why rpm meter doesnt work properly...it goes well to 4000 rpm but after that it goes down to 3000. Never shows more than 4000 . I have checked wirings at meter and they are all good. Where does the ground go from rpm meter? I have a 115 hp Mercury 1998 two strok. I suppose is same engine as yours.
On the switch box, left row, 3rd wire down (on mine) is a black wire with yellow stripe. This wire comes from the kill switch at the console. Also on that same post is a black wire. That black wire goes to a junction box between the switch box and rev limiter. If you remove the black wire and tape up the end that removes the rev limiter from the circuit. (If not careful, you could over-rev your engine, particularly when starting.) If your engine was cutting out or sputtering and you remove the ground wire and the engine doesn't cut out then you need to replace the rev limiter. My rev limiter had several cracks on the back side where it attached to the overheating sensor. If the engine is running OK, no cutout, but the tachometer (RPM gauge) doesn't read properly then you may have a bad voltage regulator. The tachometer is connected to the voltage regulator. You need to check your battery voltage when running at top speed. If you are over about 14.1 volts then the voltage regulator is probably bad. Mine was reading 18-19 volts and the tachometer wan't working. I replaced the voltage regulator and it worked again.
@@richward2288 Thank you. I have to melt down all that information :- ) but the only thing I know now for shure that vollts are not exceeding 14.volts. before start 12.2v . And after start o 13,8v. When trying to get WOT rpms engine doesn't sound right....like a rpm regulator kicks in. I have ordered a larger propeller..from aluminium 15 to 17 stainless.pitch. BTW...there seems to be both 5 and 6 wires regulators for 1998 115...I suppose the sixth ground wire is missing ..the box grounds itself?
@@reioXyhi Try removing that black ground wire I mentioned. That will disconnect the rev limiter. If your motor runs OK with that ground wire removed then you need to replace the rev limiter My original Quicksilver 3-blade is 13 -1/2" 22 pitch. I have a 4-blade to get on plane faster when I have 2 people in the boat. It's maybe 2 mph slower than the 3-blade but gets better gas mileage because I get on plane much faster with 2 people, full gas tank and full livewell. It's a Solas 13" 21 pitch.
It seems that we have difference in electrical wirings/system .yours 1995 an my 1998 ( serialnr OG635407 ) The good thing is that the regulator is up on the engine. Do you have a electrical diagram for a 1998? Maybe we could find out which black wire connected to your black/yellow is comparative with my engine....for a test as you did. Thanks taking your time 🤗 Mercury Mercruiser Marine - VOLTAGE REGULATOR (#8M0084173) public-mercurymarine.sysonline.com/Android/Default.aspx?sysname=NorthAmericacompany=GuestNA_KEY=NA_KEY_VALUElangIF=englangDB=eng
I'm sure that the reason that a service tech tossed it out was because you have to remove the lower cowling to install it. It's not easy to get to and there are 3 or 4 other screws to hold it in place. Now, why he dropped all but 2 of the screws from the air box down into the lower cowling area is anybody's guess.
Hey Rich in the video you mentioned you had a service manual where can I obtain one of those at I have the same exact motor but don't have a manual for it
Good video Rich, nice detail too👍
I sure could use some advice I have the same motor and the same symptoms as you I would like to know you said it felt like a momentary loss of power. Like hitting a log. Did it ever get worse as time went on like a big down and then full power then bog down.
Hi Brian, the symptom of sudden/momentary drop in power was the first thing I noticed. It happened only above about 30 mph. Below that it ran fine. When it did happen there was the drop in power but the overheating alarm 'chirped'. It never got any worse but I couldn't run at full throttle at all. I replaced the rev limiter and that solved the problem
Down the road a couple of seasons the motor was running fine, but if I throttled down it died and was extremely difficult to start, two times. I was on the water, about 4 miles from the dock. I thought I was going to get stuck, but I had a group 27 battery and I was able to crank enough to get it running. The next morning it started immediately. The next trip I went on it wouldn't start at all.
I ended up replacing the stator and the motor started up right away. Yay! But when I took it up full throttle it died at 4900 RPM, nose dived, dropped RPMs and went full throttle, nose dived, etc. Below 5000 RPM it ran fine (like with my 4-blade prop). It acted like it was the rev limiter again. I bought another one, same story. I disconnected the rev limiter and have not had a problem since then.
If you suspect the rev limiter, disconnect it:
On the switch box (power pack), left row, 3rd wire down (on mine) is a black wire with yellow stripe. (This wire comes from the kill switch at the console.) Also on that same post is a black wire. That black wire goes to a junction box between the switch box and rev limiter. If you remove the black wire and tape up the end that removes the rev limiter from the circuit. (If not careful, you could over-rev your engine, particularly when starting.)
Thanks for this Rich, having a similar issue with my Optimax. My situation presents slightly different, so Im wondering if it's the same cause. Again when motor is under load ( 3500 to 4000) RPM, beeping alarm, sudden drop ( 2 0r 300RPM ) in power, followed by engine chirping or cutting in and out like bad fuel). I return to idle, warning signal clears and I take off normally, Problem may or may not do present again. I guess I should do what you did and just pull the negative test againi?
If your alarm is chirping (mine would only chirp, it didn't continue beeping) when the sudden drop occurs, try my suggestion to disconnect the kill switch on the switch box. Then take it to the lake for a day of fishing and see if it happens again. I did that and there was no return of the problem. I replaced the rev limiter and haven't had the problem again. In my search, I found 2 other people with the same issue but different horsepower motors. Something else, take off the rev limiter and inspect the back. My had several cracks in it, quite visible.
I have similar issue not 100% if it’s as you described mine would only get to 3500 which is low couldn’t get on a plane backed off the throttle then got back into and seemed to fix it and since have had it fall on its face then come back to life. I found the alarm module behind my dash someone disconnected it if I reconnect it it’s a constant annoying tone.
Was your alarm a momentary chirp when it started becoming a constant issue or was it just momentary chrips
There are 2 alarms: overheating (behind the rev limiter) and low oil. My alarm was an extremely short beep that happened at the same time the engine just blinked out. It felt like I hit something, like a log. It was that short, just a thump. It happened only above 25 mph, never below, never more than a fraction of a second. When I took the rev limiter off it was cracked. I believe it was shorting out through the heat alarm or maybe jumping to that wire and making it beep. I just replaced the rev limiter because there was no other symptom for the alarm.
A continuous beep is the overheating alarm. If this has been disconnected then something is definitely wrong. My best guess (consider that I'm an amateur at outboard repair) is that the rev limiter is bad, causing you to fail to get on plane. At low throttle it's getting/sending a false signal and when you go up-throttle you give it more electrical power and it overcomes the problem.
A bad rev limiter may have caused the heat sensor to fail, causing the continuous alarm. If it were me, I would remove and inspect both, looking for obvious damage. Since the alarm is continuous now, it's probably bad. (Does it go on as soon as you turn the key?) That's a bad sensor to be disabled. Get your water intake plugged up with weeds and you can burn up your engine.
Getting to this area is not easy. If it were me, I'd replace both sensors; overheat and rev limiter. I know this is throwing parts at a problem but sometimes it's the only solution without more knowledge of outboard motors.
You can find part numbers at the Mercury online catalog, you need your serial number.
www.mercurymarine.com/en/us/parts-and-accessories/parts-catalog
@@richward2288 thanks for your insight
Hey, i have the same outboard. At WOT it kindof sounds like its hitting the rev limiter a little bit. But the tach is only showing around 4800 - 5000 rpm. Any ideas ?
Have you replaced any parts lately? I ask because I just replaced the stator and switch box in mine. The motor is running again but at 5000 RPM it drops out, falters. Below 5000 I can run for miles. I was told it was fuel starvation, but I don't think so. I think it's either the new switch box or the rev limiter
You can disable the rev limiter to see if that solves the problem. On the switch box is a terminal with 2 black / with yellow stripe wires. Trace to be sure but on mine the bottom one goes to the limiter, the other to the wiring harness and up to the ignition/kill switch. Remove that bottom wire and tape over the end so it doesn't touch anything. The other wire has the large terminal cover, leave that one connected. Run the boat again and watch your RPMs. Don't exceed 5250.
If the motor still falters then it's fuel starved, most likely. Check your fuel line hose/bulb for a disintegrating inner nylon line. Check the fuel filter for small bits of nylon, also the fuel pump. You'll need to clear out/replace the fuel lines completely
@Rich Ward hi thanks for the quick reply. New fuel tank, line, filter, and pump. It wont quite hit 5000 rpm sounds like a very faint hint of rev limiter sound. The maximum RPM is meant to 5250 ? Maybe my tach is off by a few hundred rpm
@@nickt197 You still running the OEM 3-blade Quicksilver Laser II? If you run a 4-blade the RPMs will be lower. That gave me an idea to take my 4-blade with me to the lake for a test using that one.
The rev limiter is supposed to be set for 5250 out of the box. I've never gone above that number but the motor wasn't doing anything strange. It's always been at least 5200 even with the boat speed dropped. Now when I reach 5000 the motor just shuts down to below 5000 then jumps back up and falters again, over and over but if I just drop it to below 5000 it runs just fine, 40 mph about.
I don't know when you're going back to the lake but I'm going on Wednesday, weather permitting. I've disconnected my rev limiter and I'll see how it behaves. I'll post the results here.
Hi Rich I enjoyed your video I have the exact same motor as u do. My problem is my battery is not charging will running so i changed the voltage regulator rectifier and battery will charge now but the voltage is all over the place and the motor is running poorly. I am thinking stator now, wonder if u ever changed yours?
Have you Check the battery cables ?
UA-cam doesn't always notify me so sorry this is so late of a reply.
I didn't change the stator, the limiter was the problem. My engine starts and runs well, just can't get that last 5 MPH that it used to give me. It tops out at 47 now and even not always that.
The voltage will vary as you throttle up and down but should remain steady at the same speed and not over about 14.1 volts. That's the job of the voltage regulator. At 15+ volts your wires on the regulator will start melting; mine did. I don't have the tools to replace the stator and have never pulled the flywheel. It's out of my league.
Thanks for a good video. Can I by disconnecting some wires in your video, ignore rev limiter . To cut out the black negativ wire at left side row will disconnect the function of built in rev limiter ? Right? No problems with that?___________ And do you have some clue of why rpm meter doesnt work properly...it goes well to 4000 rpm but after that it goes down to 3000. Never shows more than 4000 . I have checked wirings at meter and they are all good. Where does the ground go from rpm meter? I have a 115 hp Mercury 1998 two strok. I suppose is same engine as yours.
On the switch box, left row, 3rd wire down (on mine) is a black wire with yellow stripe. This wire comes from the kill switch at the console. Also on that same post is a black wire. That black wire goes to a junction box between the switch box and rev limiter. If you remove the black wire and tape up the end that removes the rev limiter from the circuit. (If not careful, you could over-rev your engine, particularly when starting.) If your engine was cutting out or sputtering and you remove the ground wire and the engine doesn't cut out then you need to replace the rev limiter. My rev limiter had several cracks on the back side where it attached to the overheating sensor.
If the engine is running OK, no cutout, but the tachometer (RPM gauge) doesn't read properly then you may have a bad voltage regulator. The tachometer is connected to the voltage regulator. You need to check your battery voltage when running at top speed. If you are over about 14.1 volts then the voltage regulator is probably bad. Mine was reading 18-19 volts and the tachometer wan't working. I replaced the voltage regulator and it worked again.
@@richward2288 Thank you. I have to melt down all that information :- ) but the only thing I know now for shure that vollts are not exceeding 14.volts. before start 12.2v . And after start o 13,8v. When trying to get WOT rpms engine doesn't sound right....like a rpm regulator kicks in. I have ordered a larger propeller..from aluminium 15 to 17 stainless.pitch. BTW...there seems to be both 5 and 6 wires regulators for 1998 115...I suppose the sixth ground wire is missing ..the box grounds itself?
@@reioXyhi Try removing that black ground wire I mentioned. That will disconnect the rev limiter. If your motor runs OK with that ground wire removed then you need to replace the rev limiter
My original Quicksilver 3-blade is 13 -1/2" 22 pitch. I have a 4-blade to get on plane faster when I have 2 people in the boat. It's maybe 2 mph slower than the 3-blade but gets better gas mileage because I get on plane much faster with 2 people, full gas tank and full livewell. It's a Solas 13" 21 pitch.
@@richward2288 very well. I will follow your instructions. Your humble student 👍🤗
It seems that we have difference in electrical wirings/system .yours 1995 an my 1998 ( serialnr OG635407 ) The good thing is that the regulator is up on the engine. Do you have a electrical diagram for a 1998? Maybe we could find out which black wire connected to your black/yellow is comparative with my engine....for a test as you did. Thanks taking your time 🤗
Mercury Mercruiser Marine - VOLTAGE REGULATOR (#8M0084173)
public-mercurymarine.sysonline.com/Android/Default.aspx?sysname=NorthAmericacompany=GuestNA_KEY=NA_KEY_VALUElangIF=englangDB=eng
Can I ask you some questions? I have the same motor
Sure, but I'm not an outboard mechanic. I'll answer if I can
nice vid, for power pack cover screw, take one out and match it at home depot etc, easy peasy, save some money
I'm sure that the reason that a service tech tossed it out was because you have to remove the lower cowling to install it. It's not easy to get to and there are 3 or 4 other screws to hold it in place. Now, why he dropped all but 2 of the screws from the air box down into the lower cowling area is anybody's guess.