ive seen this prob before with bad reed valves..... can take enough of an air leak not sealing properly at idle, and takes wot crank pressure to seal them properly.... but doesnt behave well in the midrange
So many things can cause this issue. Spark plugs, cruddy carbs, poorly tuned carbs, stator, fuel pump, clogged up fuel lines, bad grounds in any wiring on the motor, battery, list goes on. I am having the same issue but mine only happens at high range RPM. It runs smooth up to about 3000-3500 RPM but after you floor it and go full throttle for about 10 seconds the motor shows signs of losing power like it is starving from gas. I have learned the stator has 2 coils one for low end rpm and one for high and they can go bad separately. I am going to pull my stator and test the OHMs this weekend before I shell out $200-$500 for a new stator. I might even just say screw it and roll around at 3000 RPM and ride it out until the stator is completely dead. I don't have that much money to be replacing everything on the motor lol
Hello All, Well I ended up buying another mercury 150, Picked one up for a good price, Just couldn't say no... I am going to use the one I just bought for the summer and rebuild my original one in time, I don't have to rush now.. I can fish for the summer and when this motor dies my original engine should be ready... My main concern was I didn't want to miss this summer of fishing... I am pulling my motor off this weekend and should have this other motor on as well.. I will do all the electrical hook ups during the week.. Should be able to do a test run the following weekend.. I am ready to get back to doing some fishing.. Man I hate being land locked... Ant....
Hello, Got the trigger and the stator swapped out.. Started motor up, Sounds great... I won't know if it took care of my issue till Saturday when I can take it to the water... Ill post back what happens... Thanks, Anthony!!!
POWER HEAD AND MID SECTION FOR SALE>.. You will get the motor shown in video, The power head I do believe needs to be rebuilt.... I am not sure what is wrong with it... I change all the parts onn it and nothing fixed it... I bought a new motor so If you would like a shot to rebuild this power head here ya go.. This is a good rebuild-able power head and mid section.. For sale , Price is $800.00.... this will include power head, and Mid Section... Thank you Anthony
How did the flywheel magnets look? Did you check to see if they were loose? It doesn't seem to be electrical from what I can see. Have you checked your compression? Maybe there is a crankcase leak somewhere.
+Pete Derosario The Flywheel Looks almost new, But I swapped it out with another one just to be sure, And I also changed the rectifiers ( both of them) ..l Still have same result... I just don't get it.. Well I have just met a gentleman who has a shop nearby and he is helping me bye letting me swap parts with good known used parts to see if it changes anything.. I am going tomorrow and gonna swap out the power packs and coils, If either one of them don't do it.. I am gonna buy a Yamaha.. I am fed up with this motor...
Hi there, Did you ever get to the bottom of the problem? Got a v150 with similar issues and I've narrowed it down to zero spark on cylinder No3.... changed switch boxes and eliminated coil problem by swapping out with another.... Just trigger and stator to test now.
No, Sorry to say I replaced the motor for now... Problem has to be in that power-head... I am going to rebuild it I think... Not sure yet.. But I can tell you I went nuts trying to figure it out... There was nothing left for me to change.. I replaced everything Good Luck with yours.. Hope you fix it..
Leo Gr Not yet, I'm afraid although it spits fuel from a couple of carbs so I'm going to change to new readvalves and re seat them as well as a new trigger.
Don't waste your time and money, Trust me!!! I replaced everything on that motor and could not fix it... I assume the problem is in the power head.. I ended up getting another motor.. That pretty much fixed my issue...
I had the same exact problem. Ended up being a fuel line collapsing when throttling up. The fuel level be that was bad was one going to the fuel pump. Only way I found it was reving the engine up and I had my hand on the fuel line at the same time. Replaced all the fuel lines and the problem went away.
My 75hp 4 cylinder Mariner doing samething. Mechanic called yesterday and told me it's the reeds which are internal on the damn thing and looking at 10-15 hours labor plus parts. It's an 1986 so I don't think it's worth the money. Dunno what I'm gonna do yet at this point. It only dies mid throttle. Wide open runs perfect and runs steady at idle to 5-15mph. I've been advised to get 2nd opinion next
hello I got the same problem and it does it with the same rpms but it only does it when the motor has got hot when it is cold it does not do it I have changed ever thing but the stator and the trigger I need help my self
+Johnny Daniel I am sorry to hear you are going through the same shit as me... Well if you figure it out, Please be sure to let me know.. I am swapping power packs and coils tomorrow and if either one of them don't fix it, I am going to get a Yamaha... I tired of dealing with this thing...
Well I have a Yamaha and I have changed the powerpack and went through the carbs and the coils and fuel pump all new fuel line and clean out my gas tank the only thing I have not changed is the stator and the trigger man I no your pain and if I fined it be for you do I will let you no
+goat curry bai , I got the stator swapped out.. I noticed that when I was hooking up the wires to the switch boxes I noticed that the wires from the trigger going to switch boxes, they feel real rubbery and soft, Is this normal? Or should I swap out the trigger while I got off the flywheel... Thanks
Hello All, Latest update is I still have the same problem with this friggen Mercury... I've decided it must be something in the power head, So I am gonna break it all down and rebuild the whole power head I was going to pull the motor off and get another motor, but I know this outboard pretty well now so I mine as well get to know it a little better and open her up and see whats going on in there... I will try and get some videos of the break down.. The motor runs awesome so it cant be nothing major, I hope.. As long as the block is not cracked I will fix it... . All I know is I am NOT gonna miss this summer of fishing, I refuse Damnit...
You have three carbs on that engine, so three times the problem. I would think one or more of the carbs is not synced with the others. Complicated repair and expensive.
Hello All, I have changed the stator and the trigger, STILL HAVE SAME ISSUE... I am not sure what else I can do to fix this.. Pretty much everything on motor is new.. I am starting to think this thing is never gonna be right... I have met another mechanic at the ramp, He asked me to pull off the carbs, I am dropping them off to him 2nite.. He wants to go through them and see if he can find anything wrong in there...... I have nothing to lose at this point... This mechanic also thinks it is a fuel issue... Well if anyone else has any ideas , Please feel free to mention them as I need all the help I can get.. I would like to have it fixed bye summer... Thanks, Anthony
well i have one last adjustment to do, my mechanic told me to try adjusting butterfly / throttle adjustment where it meets the roller cam. if that doesn't do it, then I will change the stator.. It just sounds like it's in the fuel system to me and my mechanic but we could be wrong I guess..
I have done the carb adjustment, It did not have any change... Ok I am now convinced that it is not in the fuel system.. I am waiting on a stator that I ordered online and waiting for it to arrive in the mail.. Will get it swapped out and report back... I really hope this does it...
