Chrisb Posted September 1 Report Share Posted September 1 My outboard currently has a problem where it get above 4000 rpm. Other than that is runs fine. It starts and idles fine and runs fine up to 4000 but not above. Any mechanics here who can advise? I have changed the plugs with not difference. Quote Link to comment Share on other sites More sharing options...
Chrisb Posted September 1 Author Report Share Posted September 1 I guess it would be useful if I added the motor info. It is Mariner 1995, 3 cyl, 60 HP. Quote Link to comment Share on other sites More sharing options...
Markster Posted September 1 Report Share Posted September 1 Have you run some seafoam through it Chris? could your exhaust be carboned up? Quote Link to comment Share on other sites More sharing options...
Markster Posted September 1 Report Share Posted September 1 Other things i would check would be to confirm that all plugs are firing on all cylinders. Then i would check the fuel system to make sure you haven’t got a clogged filter or screen somewhere. I think its obvious, but i would also confirm you’re running clean fuel and have no ethanol “blob” in the tank. Chrisb 1 Quote Link to comment Share on other sites More sharing options...
Chrisb Posted September 1 Author Report Share Posted September 1 Regarding fuel issue I tried pushing the choke while running it started to stall out like it was flooding, so I eliminated that as the problem. Read that test on the internet. Not sure how I would check if all plugs are firing. I would expect poor idle. Quote Link to comment Share on other sites More sharing options...
Markster Posted September 2 Report Share Posted September 2 You check the plugs are firing by pulling one boot off at a time and confirming that there is a change in the running of the engine. No change- cylinder not firing. Chrisb 1 Quote Link to comment Share on other sites More sharing options...
Tyler0420 Posted September 2 Report Share Posted September 2 22 hours ago, Chrisb said: My outboard currently has a problem where it get above 4000 rpm. Other than that is runs fine. It starts and idles fine and runs fine up to 4000 but not above. Any mechanics here who can advise? I have changed the plugs with not difference. What’s it doing above 4000rpm? Sputtering? Or just won’t go above 4000 Quote Link to comment Share on other sites More sharing options...
Chrisb Posted September 2 Author Report Share Posted September 2 Just won't go. Quote Link to comment Share on other sites More sharing options...
Chrisb Posted September 3 Author Report Share Posted September 3 Took the boat out today and ran some tests. 1. Idle only goes up to 4700 at full throttle. 2. Running reverse, same results as running forward. 4000 max. 3. Disconnected spark on each cylinder one at a time. Engine would barely run each time. 4. Switched to portable gas tank. No change in performance. I am wondering if it could be the ignition module? I had to change it a couple of years ago when it completely failed. Do you think it could be doing more damage if I continue to use the engine at the lower rpm? Quote Link to comment Share on other sites More sharing options...
Markster Posted September 3 Report Share Posted September 3 I could be wrong, but i don’t think its ignition Chris, that would effect your idle as well. Based on your description it seems your running on all cylinders. in my mind, i would concentrate my attention on 1) fuel system (input- is engine getting enough? - hose, filter, or carb circuit blockage, etc) and 2) exhaust (output - carbon blocking exhaust channel?) i assume the engine ran at a higher RPM before and the prop is sized appropriately. have you tried simply draining the carb bowls to confirm there’s no crap or water in there? there should be easily accessible drain screws that can be loosened to let them drain during winterization. Do you troll alot Chris? If so, do you use a product like seaform to clear that out? Since its a 2-stroke i don ‘t think you can do any more harm by continuing to run it. If its a carbon build up and you continue to run at trolling speed your carbon buildup could be worse until those deposits are cleared out. Chrisb 1 Quote Link to comment Share on other sites More sharing options...
Chrisb Posted September 3 Author Report Share Posted September 3 Do not use this engine for trolling. 2 hours ago, Markster said: 1) fuel system (input- is engine getting enough? - hose, filter, or carb circuit blockage, etc) I thought about that, and saw a suggestion on the internet to try activating the choke. I tried that and the engine started to bog like it was flooding out. I also switched over to my portable tank to see if there was maybe an issue with the under floor tank and hoses. 2 hours ago, Markster said: 2) exhaust (output - carbon blocking exhaust channel?) Interesting you mention that. I had that exact problem on the 9.9 I use for trolling. I will try to figure out how to check this. I think I just have to drop the lower leg and I should be able to see the channels. Not a problem I have done several times before and it quite simple, 4 or five bolts and the shift rod is all it takes. I will drain the carbs and see what comes out. I do this every year in the fall so I know exactly what to do. Quote Link to comment Share on other sites More sharing options...
NiagaraRiverFisher Posted September 14 Report Share Posted September 14 Hi Chrisb , have you looked at the throttle cable travel , sometimes the cable gets dry/abit rusty/old /stretched, slips from its hold from where it should be at carbs or won't travel all the way thru the cable when called upon . keep us updated. Tyler0420 1 Quote Link to comment Share on other sites More sharing options...
Chrisb Posted September 14 Author Report Share Posted September 14 Throttle cable seems to be working fine. Found a bunch of corroded and overheated connections to the voltage regulator and repaired them with no change. I have pulled the boat out of the water for the season. I think I have exhausted everything I can try it's time for a real mechanic. Quote Link to comment Share on other sites More sharing options...
Chrisb Posted September 30 Author Report Share Posted September 30 It's time for a real mechanic. Does anyone have any name of mechanics who are good? This is a 1995 Mariner. Quote Link to comment Share on other sites More sharing options...
genec Posted September 30 Report Share Posted September 30 Erie Marine and Small Engine, southeast of Stevensville. Call John at 289-668-7745 Quote Link to comment Share on other sites More sharing options...
boogaloo Posted October 1 Report Share Posted October 1 A faulty ignition coil can do crazy things. Quote Link to comment Share on other sites More sharing options...
Chrisb Posted October 2 Author Report Share Posted October 2 Talked to John and he was very nice. Gave me some FREE advice as to what my problem might be over the phone. He says it is likely the stator as it has a low and high speed winding and high speed winding might be bad. More testing to follow. Quote Link to comment Share on other sites More sharing options...
genec Posted October 2 Report Share Posted October 2 John is great to deal with. Knows his motors, and wont rip you off on unnecessary repairs Quote Link to comment Share on other sites More sharing options...
Chrisb Posted October 5 Author Report Share Posted October 5 What about aftermarket parts? Any opinions vs the much more expensive Mercury branded parts? Quote Link to comment Share on other sites More sharing options...
genec Posted October 5 Report Share Posted October 5 No idea, but John could tell you if there are sources for them, and if they would be reliable Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.