1990 Johnson 175 hp starting rough

jamesbalog · #1 07-07-2011, 06:12 AM

I have a 175 horse johnson on the back of my v20 and she starts rough every time. Once she's running it will run like a champ. I plan on trying to change the plugs but other than that is there anything else I should look for?

I'm not the most mechanically inclined person but I don't want to take it to the shop for a tune up if I don't have to so any help would be appreciatrd

Cam · #2 07-07-2011, 06:32 AM

Sounds to me like a typical 2 stroker.

THEFERMANATOR · #3 07-07-2011, 08:49 AM

Is it a looper or crossflow? How's the fuel pump? You do pump the primer bulb until it is hard before cold starting? When were the carbs last done? Is the fuel primer solonoid working? If you don't pump up the primer bulb before cold start, then there will be no fuel pressure present for the primer solonoid to inject for the cold start and will require extra cranking until it builds fuel pressure.

jamesbalog · #4 07-07-2011, 09:22 PM

Quote:

Originally Posted by THEFERMANATOR

Is it a looper or crossflow? How's the fuel pump? You do pump the primer bulb until it is hard before cold starting? When were the carbs last done? Is the fuel primer solonoid working? If you don't pump up the primer bulb before cold start, then there will be no fuel pressure present for the primer solonoid to inject for the cold start and will require extra cranking until it builds fuel pressure.

as i said im not the most mechanically inclined person in the world. i am 90 percent sure it is a looper. yes i do pump the bulb until it is hard. i jsut bought the boat so i am unsure of when the last work was done on the carb or the rest of the motor.

when i went to look at it the outboard fired right up first turn of the key everytime (go figure lol)

THEFERMANATOR · #5 07-07-2011, 09:30 PM

The first start of the day will normally take a little while(maybe 3-5 seconds of cranking with the choke engaged), but after that they start pretty quickly.

jamesbalog · #6 07-07-2011, 10:45 PM

Now that I think of it the choke may be my problem. On the merc I had on my last boat I could hear I distinct clicking sound with the choke engaged, I am not hearing any clicking with this motor.

Also the last time I had the boat out it wasn't just the first start that gave me problems. But if I took the boat out of gear and gave it gas it would fire right up.

THEFERMANATOR · #7 07-08-2011, 10:57 AM

Quote:

Originally Posted by jamesbalog

Now that I think of it the choke may be my problem. On the merc I had on my last boat I could hear I distinct clicking sound with the choke engaged, I am not hearing any clicking with this motor.

Also the last time I had the boat out it wasn't just the first start that gave me problems. But if I took the boat out of gear and gave it gas it would fire right up.

You have to pull the cowling off to hear the choke on the OMC's as it is simply a primer solonoid not an actual choke mechanism on the carbs. And most engines will start better in neutral with the throttle opened slightly. Sounds like you need to go through the carbs and do a link and sync and make sure everything is in order. When in doubt it is much cheaper to do the maintence than an engine repair.