2003 Johnson 175 J175 GLSTE?

[Les Young]

Took a buddy & his small son fishing lastnight & every time i moved spots it just plowed for a long ways before planing off. I tried choking it & it bogged down so i'm assuming it's electrical. When it finally broke over it was only at 2700 rpm. After planing off it appeared to run good but the lake was severely trashy with huge logs etc. from heavy rains so all i could do was keep it on plane. I noticed the idle is a little slow at 560 rpm in gear. I'm wondering if my power pack might have gone bad. I'm going to see if my mechanic has one i can try. Any suggestions that you guys can think of that i could easily look at? Thanks

[Bighare2]

Spark plugs and ignition coils will do the same thing. Recommend the basics before assuming a bad power pack.

[Les Young]

Spark plugs and ignition coils will do the same thing. Recommend the basics before assuming a bad power pack.

Bighare2 thanks. It has new plugs in it. I put plugs & wires on a while back & put new plugs in it the other day. I can’t tell that it’s missing at all. Just low idle & the plowing when trying to get on plane. Carbs were rebuilt a while back too.

[Bighare2]

My recommendation of basics is also a spark check with a spark tester. Good spark, with plugs installed will jump a 3/8 to 1/2 in gap on proper spark tester.

[Les Young]

��Thanks

[Les Young]

Forgot to mention that this motor has had an issue for awhile that i haven't been able to figure out. After making a wot run of probably 8 miles or so it acts like it drops a cylinder & the sound of the motor changes & rpm drops around 300 rpm. I can let off run for a little while then go to wot again & it runs perfect for a wjile until it does it again & i can repeat it over & over. Sorry i forgot about it doing it because i've been crappie fishing & i haven't ran wot in a long time. Hopefully it helps.

[Les Young]

I did a spark test & 2 out of 3 cylinders weren't firing on the left side standing behind the motor. Sound like the power pack needs replacing to you guys? If so i'll do power pack, optical sensor, coils & wires. I changed plugs last weekend.

[Les Young]

Any suggestions or am I thinking right? Thanks

[Les Young]

Replaced power pack, optical sensor, plug wires & plugs & still has the same low idle & only 2700 rpm on holeshot but runs good after getting on plane. Carbs were rebuilt & lync & sync done a few months ago, I’ve thought the idle was a little slow ever since the rebuild. Could this be a jetting issue or something wrong with the lync & sync? Any suggestions? Thanks

[Simply_M]

Don’t forget about the third piece of the puzzle…compression. All cylinders been checked again for spark after new parts?

[Les Young]

Don’t forget about the third piece of the puzzle…compression. All cylinders been checked again for spark after new parts?

Mechanic checked it when he rebuilt carbs & said it was perfect but I forget the numbers. I replaced all three coils today & started it in the muffs & there’s a noticeable difference innthe sound of it. I’ll lake text it now & see what happens.

[Simply_M]

Something could have happened to make it loose compression on one or more cylinders. If coils don’t fix it, go back through and check the basics again.

[Les Young]

Something could have happened to make it loose compression on one or more cylinders. If coils don’t fix it, go back through and check the basics again.

Still slow idle & only got to 4800 rpm & then bogged. Can let up on hot foot & it picks right back up open it up again until hitting the 4800 rpm then bogs again over & over. Guess I’ll be checking compression again. I have good spark in all cylinders now & clear rollers are intact & everything else looks right. May have to check fuel pump out. Going to see if mechanic can meet me at the lake one evening to show him what’s it’s doing since I obviously ain’t figuring it out.

[Simply_M]

I feel for you. High speed problems have to be the worst thing. Might pull the plugs and see if they all look the same and nice brown color.

[Les Young]

I feel for you. High speed problems have to be the worst thing.

Wouldn’t be so bad if it was just high speed but the holeshot is awful too. Have buddy sit up front until planing then it runs & sounds normal but you can’t go w o t around here right now for the huge logs & debri fields everywhere. Only things not replaced are stator & rectifier except for either rebuilding the vro/ oms whatever they call it lol or atleast the fuel side of it or replacing it. Can’t get in to see a mechanic right now at all because they’re so covered up. Mechanic rebuilt carbs & done lync&sync by the book. I wonder how bad & easy a job it is to rebuild the fuel pump & what all that involves since kits don’t cost that much?

[Simply_M]

As a diy type person I meant trying to work on an outboard with high speed issues is impossible. I don’t like hanging off the back of the boat at any speed. At least an idle problem can be worked out at home in a test tank. Never done a pump rebuild. A bad fuel delivery problem can be tested by pumping the ball while the engine is acting up. If it changed both to the low idle and lower max rpm at the same time, I wouldn’t think that would be fuel delivery issues. A starved carburetor of fuel probably won’t take any throttle. However, each part of the puzzle has to be 100% operational to be certain what the actual problem is.

[Les Young]

As a diy type person I meant trying to work on an outboard with high speed issues is impossible. I don’t like hanging off the back of the boat at any speed. At least an idle problem can be worked out at home in a test tank. Never done a pump rebuild. A bad fuel delivery problem can be tested by pumping the ball while the engine is acting up. If it changed both to the low idle and lower max rpm at the same time, I wouldn’t think that would be fuel delivery issues. A starved carburetor of fuel probably won’t take any throttle. However, each part of the puzzle has to be 100% operational to be certain what the actual problem is.

Low idle to the point of almost stalling when on the water in gear. Was by myself today so couldn't really test holeshot under a load but bogged down with my buddy& me Friday night. Today it would only hit 4800 & you could feel it bog down. Then i'd let up & it would pick up & run fine until i went to wot again. I could make it repaet it over & over is why i'm wondering if it's fuel related.

[Simply_M]

Does sound like fuel starvation. Need to have some way of pumping the primer bulb to see if it makes a difference. Also pump the bulb with the engine off sitting level and see if it will get firm to the point where you can’t really squeeze it anymore. Keep it squeezed and see if it slowly gets softer until it collapses. This will test the fuel system for leaks.

[ChampioNman]

Make sure your high speed orifices are all fully seated.

[Les Young]

Make sure your high speed orifices are all fully seated.