30 hp johnson cycling at high speed

farfel

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May 27, 2011
Messages
22
Re: 30 hp johnson cycling at high speed

already swaped out plugs. kind of dangerus to do the timing light thing while underway and being alone in the boat. so i'm going to replace both coils and check it out again. i will keep you informed.
 

farfel

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Joined
May 27, 2011
Messages
22
Re: 30 hp johnson cycling at high speed

ok put in new coils engine starts by the count of two. very nice! ran the boat around all morning. no problems. putt-putted around . all good. started to back to dock hit the throddle started same crap put ut in neutral hit it again and it took off like a bat all the way back. so it looks like most of it is gone but it makes me think maybe its the stastor assy part #45. is this where the spark signal originates? and could it be an intermittant thing with it stators seem pritty simple.
 

AlTn

Commander
Joined
Mar 9, 2010
Messages
2,813
Re: 30 hp johnson cycling at high speed

as Daviet has advised...a timing light on each plug wire when the problem exist is the best way to eliminate or confirm an ignition issue...your stator <on this model> is for battery charging only, it has a separate charge coil for supplying current for the spark. The free stuff to do is clean the grounds for the coils and powerpack. Unplug and clean with rubbing alcohol or electrical cleaner , each plug, male and female ends.
 

farfel

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May 27, 2011
Messages
22
Re: 30 hp johnson cycling at high speed

ok i'll check ou the charge coil see what happens
 

farfel

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May 27, 2011
Messages
22
Re: 30 hp johnson cycling at high speed

ok all electrical conections opened cleaned & dielectric grease put on them. they all looked like new from the factory. nothing changed. only thing i can now think of os the slow system that limits rpm to 2500rpm when the engine is hot. but the alarm never goes off could it be that or is it that the water temp here is in the low 80's so that the system is on the brink or the temp sensor is bad?
 

farfel

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May 27, 2011
Messages
22
Re: 30 hp johnson cycling at high speed

ok took the boat out again today emptied the gas tank put new fuel in ran te hell out of it putt-putt around for about an hour then took it up to speed no problems. looks like i had gotten some bad gas so it cost me a bit to find that out. but now i know the engine is perfect and won't let me down when i'm out in the salt
 

AlTn

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Mar 9, 2010
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Re: 30 hp johnson cycling at high speed

glad you found it..kind of maddening sometimes
 

restornator

Petty Officer 1st Class
Joined
Aug 15, 2009
Messages
361
Re: 30 hp johnson cycling at high speed

it's the S.L.O.W. safety feature, your engine is either overheating, or the water temp sensor has gone bad. you need a factory service manual to check each fault. If the engine is cool and the temp sensor checks out, you'll need a new power pack
 

cfoodluva

Recruit
Joined
Jul 15, 2011
Messages
4
Re: 30 hp johnson cycling at high speed

i have a 1968 20hp runs great without cover on, and when cover is put on, theres no power at full throttle..need help.
 

farfel

Cadet
Joined
May 27, 2011
Messages
22
Re: 30 hp johnson cycling at high speed

engine runs fine now that i've dumped the gas but a new problem has popped up from the vibration when it was cycling. looks like all the rubber mounts are shot as i can jiggle the whole engine. i've orderd the new mounts and they should be in in a few days. but the problem is that i have no idea on what is the best way to replace them without taking most of the engine apart. any suggestions?
 

boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
Re: 30 hp johnson cycling at high speed

cfoodluva, You shouldn't Hi-Jack a thread, but in answer to your question, you got a bad exhaust leak.
 

farfel

Cadet
Joined
May 27, 2011
Messages
22
Re: 30 hp johnson cycling at high speed

fixed all the mounts what a job took 4 hours most of the time was spent removing broken bolts . drilling and re-taping.i don't understand why when they make these outboards they don't use anti-sieze compound as so many of these engines are going into salt water. thats either being cheap or they think these things last forever
 

Cofe

Lieutenant Commander
Joined
Apr 23, 2009
Messages
1,883
Re: 30 hp johnson cycling at high speed

Antiseize for marine applications is the only way to go. Other kinds of antiseize will cause problems.
 

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farfel

Cadet
Joined
May 27, 2011
Messages
22
Re: 30 hp johnson cycling at high speed

yup thats the good stuff been using it on evereything for years no problems.
 

farfel

Cadet
Joined
May 27, 2011
Messages
22
Re: 30 hp johnson cycling at high speed

when i started this thread i thought after all this replacement and cleaning the engine would run fine and it did for awhile then it started doing the same thing again. last time i had it out i had the engine cover off so i could see if i could see anything wrong. well!!!! the engine was running hot and the slow alarm was not going off. so i pulled the water jacket cover to check the thermostat, guess what i found. there were sea shell fragments in the thermostat spring keeping it from opening. replaced the thermostat and gaskets and now it runs like a dream. guess thats what happens since i fish in 1 to 3 ft of water but i dont understand how they got past the screens on the water pick up. well anyway now that i know what to check i'm good
thanks guys for all your info but flats fishing is different. different problems.
 
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