78 stinger 75hp wont turn over with spark plugs in...

[78ImperialT]

PLEASE HELP!!!

i just finished restoring a 1978 imperial tri-hull from the trailer up...i mean everything...i thought. the one thing i didnt replace was the waterpump. this is my first boat and no one informed me that an outboard that has set for 7 years needs a new water pump. i told them water was coming out of the little tube and they said "good".

it started perfectly, shifted perfectly, ran wide open as a case knife for 2 hours (this baby will scoot). "sputter, spuuter" and it quit all of a sudden. not like i turned the key off..more like somebody instantly welded the piston to the cylinder. 6 hours and 20 miles of lake later i got it home and got the head off. the pistons and rings and cylinders were untouched. like a miracle from god!!! i replaced the head gasket and the WATER PUMP...lol. and now this...

when i turn the key it does this...woont...woont...woont...almost like the battery is dead, only its not. if i take the spark plugs out...it turns over just as expected. put the spark plugs back in...woont...woont...woont.

im not stupid but im not an outboard mechanic either. i understand 4 stroke motors much better and dont really understand reed valves and all that other 2 stroke stuff.

please help!!!

model number 75ELR78
year make 1978 johnson stinger 75hp

 

[billy4hp]

Re: 78 stinger 75hp wont turn over with spark plugs in...

PLEASE HELP!!!

i just finished restoring a 1978 imperial tri-hull from the trailer up...i mean everything...i thought. the one thing i didnt replace was the waterpump. this is my first boat and no one informed me that an outboard that has set for 7 years needs a new water pump. i told them water was coming out of the little tube and they said "good".

it started perfectly, shifted perfectly, ran wide open as a case knife for 2 hours (this baby will scoot). "sputter, spuuter" and it quit all of a sudden. not like i turned the key off..more like somebody instantly welded the piston to the cylinder. 6 hours and 20 miles of lake later i got it home and got the head off. the pistons and rings and cylinders were untouched. like a miracle from god!!! i replaced the head gasket and the WATER PUMP...lol. and now this...

when i turn the key it does this...woont...woont...woont...almost like the battery is dead, only its not. if i take the spark plugs out...it turns over just as expected. put the spark plugs back in...woont...woont...woont.

im not stupid but im not an outboard mechanic either. i understand 4 stroke motors much better and dont really understand reed valves and all that other 2 stroke stuff.

please help!!!

model number 75ELR78
year make 1978 johnson stinger 75hp

Are you able to turn the engine over with a breaker bar by the flywheel nut with the spark plugs in without a large amount of effort? You are supposed to be able to rope start these engines in case of a emergency or starter failure...

Other than that I would double check the cable connections and ensure the battery is fully charged..

HTH

 

[78ImperialT]

Re: 78 stinger 75hp wont turn over with spark plugs in...

the motor will turn over its not locked up...i can turn the flywheel by hand. the battery is fully charged.

i think its some sort of compression lock but i dont know whats causing it.

thanks for the input though

 

[Lion hunter]

Re: 78 stinger 75hp wont turn over with spark plugs in...

Did the water pump fail? Sure sounds like water in the cylinders, or a piece of the pistin is hitting the plug. Do you have to pull every plug for it to turn over or is it a particular plug? I would have someone turn the motor over w/o the plugs and see if there is water coming out.

 

[78ImperialT]

Re: 78 stinger 75hp wont turn over with spark plugs in...

ok...guess this would help.

i removed the head...all pistons and cylinders are good. no water either. also...i replaced the waterpump.

if it overheated ... what could have happened to cause this compression lock?

 

[tashasdaddy]

Re: 78 stinger 75hp wont turn over with spark plugs in...

90% of starter problems are bad connections. remove and clean both ends of the battery cables, so that they are shiney, also the cable from the solenoid to starter. check for nicks in the cables. and make sure the connectors are on the wire good. the cable tend to corrode from the inside out, if nicked, corroded wires, and connections, heat up and cause resistance to the follow of electricity, thus the starter doesn't get enough. you can also take jumper cable pos battery post to large post on starter. with a good connection, the engine should spin. then if the starter is good clean everything and retest. then trouble shoot solenoid. starters can be rebuit at a starter/alternator shop, much cheaper than a new one.

also have the battery load tested at the auto parts store, free, i've had new batteries go bad

 

[Lion hunter]

Re: 78 stinger 75hp wont turn over with spark plugs in...

Now I think I'm understanding your problem and I think TD is right about it being electrical. I didn't think about a bad battery. With the plugs in you have compression which creates more of a load.

 

[kenmyfam]

Re: 78 stinger 75hp wont turn over with spark plugs in...

Agree with the connections. Best place to begin with and it's a free fix if that is all it is !!! My kind of price.

 

[78ImperialT]

Re: 78 stinger 75hp wont turn over with spark plugs in...

Agree with the connections. Best place to begin with and it's a free fix if that is all it is !!! My kind of price.

ok...all the cables are new...but i checked them anyway. the starter and battery are also good. took them this morning and had them tested.

this is so frustrating...anyone want to buy a boat...CHEAP

 

[Lion hunter]

Re: 78 stinger 75hp wont turn over with spark plugs in...

Sorry to keep hounding you with obvious questions, trying to make sure we don't overlook anything. Are you using a marine starting battery or a deep cycle? Have you taken a known good battery (from your truck) and tried that, or put your boat battery in your truck and see if it will turn it over. Whatever you do don't get frustrated and grab the battery charger and try to jump it while hooked to the boat.

 

[eaglejim]

Re: 78 stinger 75hp wont turn over with spark plugs in...

My rude went through something like that it had a couple things wrong with it but it turned out to be a power pack,you have yourself one nice boat,hope that helps

 

[78ImperialT]

Re: 78 stinger 75hp wont turn over with spark plugs in...

update...

you guys arent going to believe this!

my neighbor is not a mechanic...not even a little bit. he was helping (watching) and said this...

"if it overheated and dried everything out why dont ya put some penetratin oil in it?"

i grabbed the pb blaster and removed the plugs and soaked the pistons...raised the motor up on the transom saver and let it set for a few hours...VIOLA!

it turned over...smoked a lil from the pb blaster and ran perfect! took her to the lake and couldnt be happier.

thank you guys for the help and for the motivation!

 

[billy4hp]

Re: 78 stinger 75hp wont turn over with spark plugs in...

update...

you guys arent going to believe this!

my neighbor is not a mechanic...not even a little bit. he was helping (watching) and said this...

"if it overheated and dried everything out why dont ya put some penetratin oil in it?"

i grabbed the pb blaster and removed the plugs and soaked the pistons...raised the motor up on the transom saver and let it set for a few hours...VIOLA!

it turned over...smoked a lil from the pb blaster and ran perfect! took her to the lake and couldnt be happier.

thank you guys for the help and for the motivation!

Glad it ran like a top, now do a compression test....

JMHO

 

[78ImperialT]

Re: 78 stinger 75hp wont turn over with spark plugs in...



maybe the vid works...???

 

[billy4hp]

Re: 78 stinger 75hp wont turn over with spark plugs in...

Link to compression test how to's:

http://forums.iboats.com/showthread.php?t=313884

 

[tashasdaddy]

Re: 78 stinger 75hp wont turn over with spark plugs in...

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