115 blue stripe hits a wall @ 3000

[king_butt_head]

Hi all i have what i think is a 75' mercury 115 hp. inline six. It's a blue stripe metal cowel serial # 6198853. The motor runs great, start's right up, and goes good untill about 3000 rpm then just hit's a wall won't get the boat on plane. it dosent sputter or anything just won't go past 3/4 throtle. It almost sound's like someone is shoving a sock in the carb like it lost spark. I cleaned the carbs, rebuilt the fuel pump, tried priming the bulb while it does it, new cap rotor wires and plug's. so it's not a fuel or tuneup problem. I think from what i'v been reading that it's the stator or trigger. Can anyone please give me any info on what else it could be mabe? or what year the motor is exactly? The only other thing i just saw today is that the red wire from the lower switchbox that goes to the idle stabilizer disentagrated when i poked it lol. all the other wires look good and the switchboxes and eavrything look's new. thank's eavrybody

 

[king_butt_head]

Re: 115 blue stripe hits a wall @ 3000

According to the lookup spot my motor is an 82 covers # 60 somethin to 62 somethin. But i thought motor's from the 80's had a brown stripe? Somebody musta changed the cowel or graffics or somethin.

 

[Solomon Shaffer]

Re: 115 blue stripe hits a wall @ 3000

My 81 has a blue stripe.

I would do a stator test. If it's hitting a "wall" then it's likely that the highspeed stator has gone out...though in all honesty I'm not sure what RPMS the low/high stators cover.

 

[79Merc80]

Re: 115 blue stripe hits a wall @ 3000

I hate to be the one to tell you this, but 1/2 way thru 1979, the distributor's went away on the inline 6 Merc's/Mariners. If yours has a distributor, then it's an early 79 or older.

Craig

 

[Faztbullet]

Re: 115 blue stripe hits a wall @ 3000

Actually it was 78 1/2 that the ADI system was introduced to the inline models. Disconnect the rectifier and retest, if it runs ok check stator output and rectifier. If this dont help take a timing light and hook on the spark plug wire and see which cylinders are dropping and post back results.

 

[king_butt_head]

Re: 115 blue stripe hits a wall @ 3000

my bad i have coil pack's. I think it's the high speed wind in the stator also i just wanted a few other opinions really before i spent the 300 on a new trigger and stator. I didn't know they made a blue strype in the 80's does yours have a metal engine cowel also? Oh one other thing i forgot to mention is that it only seems to do it when the prop is under load while the boat is moving. I.E. when i drag the thing all the way to the lake to find out it's still not right...... I even tried sticking the back end in my neighbor's pond with it straped to the trailer still and could not duplicate what it does on the water. sure shoved my truck though.... Could the prop be 2 steep mabe? I had a 19 on there and switched to a steeper 21 and it does the same thing, i know i should have bought a 17. was an accadent It's on a 1973 16' sea ray closed bow.

 

[king_butt_head]

Re: 115 blue stripe hits a wall @ 3000

should i have any continuity between the red and red , or red and yellow wires coming from my stator? My meeter is showing some resistance but there is an open circut between any wires i put it on.

 

[king_butt_head]

Re: 115 blue stripe hits a wall @ 3000

I unpluged the regulator and it started right up. I have 10.5vac from the stator to the regulator and 12.5vdc coming out of it. I have spark on all cylinder's. I need to take the boat to the lake and have somebody else drive while i check each sparkplug wire @ wot to see if any of them are being droped. what a pain in the @$$

 

[blue90HP50]

Re: 115 blue stripe hits a wall @ 3000

I think if it runs good to 3000 rpm's and no higher, you need a stator. I changed only the stator, later after buying 2 switchboxes, and mine runs good. 19 pitch prop. I bought OEM for the better warranty. Good Luck
Blue

 

[reynold460]

Re: 115 blue stripe hits a wall @ 3000

i have similar problem my boat runs to 5000 rpm then drops back to 3000 rpm then will run back up to 5000 rpm back and forth put switch boxes on it and still same thing tryin to get trigger off to change it now my motor is a 1984 mariner