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1977 85hp johnson problems starting

waxie1986

New member
i just got a 1977 cheetah and it has an 85 hp johnson. it runs pretty good... once its running. ive put the boat in the water 3 times since i got it 2 days ago. first time i couldnt get it to start. the second it started. warmed up ran good... did some traveling on the lake at full speed. then came in to the dock and ate lunch started up again pretty easy. then changed tanks due to fuel ran out.. and then i started again ...easy..

THEN.. today i went out and again it wouldnt start...

the guy gave me starting instructions. pump bulb...open vent... push key in (choke) turn key... and hold the warm up lever up to start and keep it there until the motor should be warm.... he said it takes usually 45 seconds to start.

now... to me holding a key and turning over a motor that long doesnt seem right? like it would be damaging. any ways since im new to boating and this forum. what should i do? where should i look.. why would it start then not then start then not?

.. just want my boat to run! thanks in advance.
 
Re: 85 johnson problems starting

You shouldn't crank the engine for more than 15 seconds at a time, and then after that there should be a 2-minute cool down before you make another attempt. The starter motor isn't designed to run for long periods of time; it can heat up and burn the windings out. :eek:

Seems to me like one of two things is happening. Either the pump bulb isn't getting enough fuel into the carbs so the engine can start (thus cranking it for a long time allows the fuel pump to draw it in) or you have low compression. Is the pump bulb hard? Once you fill the carburetor bowls the needle valves should shut off and it should be felt as resistance in the pump bulb. You have to squeeze the bulb repeatedly until this happens; it might take a dozen squeezes at times. If it *never* gets hard, the check valve in the bulb is probably bad, and you'll need to replace it. They're not terribly expensive.

Are you getting spark when it won't start? There needs to be enough spark energy to jump a 7/16ths-inch gap, and the spark should be blue in color. You'll need an automotive spark tester to check this, or you can make one with a piece of wood and some nails.

If your pump bulb is hard, your spark is strong, then it could very well be compression. You'll need to set up a compression test and see the numbers you get, all of which should be within 5-10% of each other. Compression can go up when the engine is warm thus making it easier to start. You might have some stuck rings or carbon buildup.

What year is the engine? You might have the same year (77) I have...
 
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Re: 85 johnson problems starting

yes the bulb gets hard. i just went out there to take a look at the motor one of the plus was finger tight, i pulled it out there was some oil on it...

the motor doesnt seem to even really try to start meaning like no sputtering or anything when im cranking.. then all of a sudden poof starts. if that helps. timing??

if i had bad compression or carbon build up it wouldnt plane out would it? like have enough power to? just asking questions really.

i will try to do a spark test and what not this evening. how exactly would i administer a spark test?
 
Re: 85 johnson problems starting

i just switched the fuel line with one off my other boat just to check if it helped at all before i got back in the water. and when i took the old line/bulb off the bulb was still completly firm no play at all with it disconnected at both ends.... is that normal? i figured the pressure would release when it was unhooked.
 
Re: 85 johnson problems starting

The fitting at each end keeps the fuel from leaking out. Normal. If I recall correctly, your vintage engine had a real bear for an ignition system. You really had to have a good battery and decent connections on the cables or these engines were hard to start. A marginal battery might have enough power to turn the engine over ok, but not fast enough for decent ignition. You should also check your carb to make sure the choke closes completely when you press the key.
 
Re: 85 johnson problems starting

got it going... was probably a combination of fuel line bulb gas tank... spark plugs or battery replaced all with new... and boom it starts! immediatly... bad news went to start it again later... starter died!!! well now i guess its onto the starter and try again tomorrow.
 
Re: 85 johnson problems starting

Congrats on the success. It is fairly common for solenoids go bad on outboards. You may want to check that before diving into the starter.
 
Re: 85 johnson problems starting

when i try to turn the key it clicks.. (solenoid does) and no turns from the starter. i hit the starter with a wrench and tried and got a little turn... then nothing after. just the clicking from the solenoid. you think it could still be the solenoid? if its clicking and nothing from the starter?
 
Re: 85 johnson problems starting

ok now i guess im confused. i just went out and thought hey what the hell take a look at it.. tried to start it.. and turned the key and the starter turned over the motor... slowly... but it turned it over.. when before all i was getting was clicks. now im kinda confused do starters go "weak" where they will only turn slowly.. the battery was just fully charged so its not dead. hmm ?
 
Re: 85 johnson problems starting

Starters can have worn brushes, gunked up commutator, etc. What you describe can be a common starter issue. I would connect a voltmeter on the starter side of the solenoid, and see if you get voltage when the solenoid clicks.
 
Re: 85 johnson problems starting

i just ordered both items to be here monday.. hope its one of those two issues... and i can finally enjoy my boat with out the worries!!
 
Re: 85 johnson problems starting

well it was a starter it seems that could have been the issue almost all along starts repeatedly. quickly everytime.
 
Re: 85 johnson problems starting

Check to see if starter gears are jammed against flywheel gears. Slight tap with hammer fixed my problem.
 
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