1985 johnson 60 loosing power

Hi everyone I've been lurking and searching for all my answers but have a new intermittant problem I'm hunting..

I just recently picked up an 1985 17'bonito cc with a 1985 johnson(j60ELCOD) cheap. The boat like most was neglected for a couple years. I replaced most of the boat wireing, replaced necessary wireing in the motor. Checked the cooling system its ok no overheat, cleaned and rebuilt the carbs. Replaced lower unit oil. etc..etc.. Boat would start and idle ok just seemed like it needed to be run. Finally got it on water for test run. It started just fine idled just a little rough, when I throttled up boat gained a few hundred rpm but not much and wouln not plane. Took a small loop around lake at what would be about 1/3 throttle but would not power up any more. After about 5 min pushed to wot, boat wouldn't speed up at all but stayed at low power, engine then on its own kicked up to full power and popped up on plane. Would run at wot for a while then every now and then it would drop to 1/3 power on its own. Boat would start perfect everytime, and no problem moving at no wake speed. When boat dropped power I squeezed fuel bulb with no effect on the motor. Have glass filter so I know it was getting fuel, took carbs apart again they are ok..
I'm looking for other ideas, I'm leaning towards intermittant coil issue and will test coils when I can. While searching I found some motors have a SLOW feature, does this motor? Some of my problems seem to mimic the slow shutdown I think...As far as I can tell the temp sensor on the motor has its wire cut(brown) and the alarm in the cc just has its black and red wire hanging loose.(so no active alarm system) I'll keep fighting the good fight, but was wondering if anyone has any ideas or input for me.

by the way I have a seloc(argh) and oem manuel is on its way so that is not required input lol...

Re: 1985 johnson 60 loosing power

welcome to iboats.

your motor does not have SLOW. check your compression, and spark with testers.

i will say that you probably, have dirty high speed jets in your carbs. also change all fuel line to alcohol resistant lines. read Ethanol, Carb cleaning, compression test here.

http://forums.iboats.com/showthread.php?t=299680

Re: 1985 johnson 60 loosing power

Carbs were cleaned before and checked after, no problems in the carbs. Fuel line is ethanol resistant, but I will be changing them out also, along with new fuel filters again. I have read all carb cleaniong posts, and ethanol problems(have been dealing with ethanol problems for years so nothing new to me) Spark is strong, but cant help thinking there is some sort of intermittant ignition problem that I haven't chased down yet. Thanks for the input I will check all again and continue the hunt

edit: compression is good also...

Re: 1985 johnson 60 loosing power

i still say high speed jets, or the link n sinc needs to be reset.

Re: 1985 johnson 60 loosing power

Check the ignition coils by using an inductive timing light; they may be breaking down once heated.

It does sound as though one or more of your float valve needles may be sicking.

Re: 1985 johnson 60 loosing power

ezeke said:

Check the ignition coils by using an inductive timing light; they may be breaking down once heated.

It does sound as though one or more of your float valve needles may be sicking.

Click to expand...

I've rebuilt approx 30 carbs in the past and have never seen the inside of a carb as clean as these there wasn't a spec of anything. I checked floats they seemed ok and needle and seat were sealing(blow test) and reset float level. Under high light was able to notice slight trace of clear sticky ooze on top coil can't figure where its comin form .........just checked out the coil with a magnifying glass and have spotted a small crack just starting...looks like problem solved.....

Just found a donor motor for asst parts, but was wondering if the 1985 and the 1986 johnson 60 had interchangeable lower units?

Tashasdaddy and Ezeke I want to thank you both for acting as my sounding board. I really apppreciate it....I will let you all know when I get new coils in..

Re: 1985 johnson 60 loosing power

Well put two new coils on rechecked all engine grounds and took her out for test today. Awsome power didn't drop a cyl once. Medium and full throttle make the engine purr like a kitten, but at low speed/no wake speed the engine seems to be running a little rough. Starts and idles fine, just rough in gear with lo throttle. Carbs are clean/rebuilt, I'm going to hunt for a possible vacume leak. Any other ideas??