1997 15 hp four stroke, new to me, first 4 stroke, pos

[dkonrai]

picked up the long shaft johnson 15 hp 4 stroke. it needs a lot of minor items, but the parts are so expensive compared to running a 2 stroke.
weight, it is 123 pounds, and my 92 30 hp weighs less, but twice the power hmmm. i bought the motor for 300.00 with the tank, but am ready to drop another 300 in parts.
check out this impeller that the po said was replaced


i need to change the timing belt, obviously the water pump, rebuild the carb, change plugs. i have to pull the ph to change the bad lower cowling seal.
why are there so many parts and plastic pieces?

question,
owner said that fuel kept getting into the oil. im assuming that the fuel diaphragm is shot. any thoughts?
here are some shots of the motor


dino

 

[JB]

Re: 1997 15 hp four stroke, new to me, first 4 stroke, pos

http://forums.iboats.com/engine-fre...4stroke-making-oil-willy-b-wright-158085.html

 

[seahorse5]

Re: 1997 15 hp four stroke, new to me, first 4 stroke, pos

Your water pump shows the classic signs of running out of water, melting the rubber from both friction and exhaust heat.

 

[dkonrai]

Re: 1997 15 hp four stroke, new to me, first 4 stroke, pos

http://forums.iboats.com/engine-fre...4stroke-making-oil-willy-b-wright-158085.html

JB,
that explains alot. the po, used the motor as a trolling motor. he never, ever ran it above 2000 rpm. it spent its life slow trolling a i/o. my buddy said the same thing, that fuel was in the oil because it idled, and never got hot enough.
very interesting. thank you good reads!
dino

 

[dkonrai]

Re: 1997 15 hp four stroke, new to me, first 4 stroke, pos

Your water pump shows the classic signs of running out of water, melting the rubber from both friction and exhaust heat.

i have seen about 50 motors, and this is one of the top five worst case water pumps.

dino

 

[boobie]

Re: 1997 15 hp four stroke, new to me, first 4 stroke, pos

Nice clean looking motor. Make sure you find all the impeller pieces.

 

[dkonrai]

Re: 1997 15 hp four stroke, new to me, first 4 stroke, pos

boobie,
yes thank you motor is pretty clean claims it is under 100 hours of use. i flushed the heck out of the motor. made a flush attachement, with a 3/8 clear hose. i can shove the hose over the water pick up tube, and blast out what ever is in the motor. works pretty darn good i have flushed out about 4 motors since i made it. cant believe it took me so long to make a flusher.
dino

 

[jbjennings]

Re: 1997 15 hp four stroke, new to me, first 4 stroke, pos

What's not to love about a 4-stroke 15hp?????

Indeed, it will probably be a nice motor after you finish it. I do like the quietness and silky-smooth idle when they're running right.
I agree, he replaced that impeller right before he ran it out of water for about 5 minutes and fried it....

 

[dkonrai]

Re: 1997 15 hp four stroke, new to me, first 4 stroke, pos

What's not to love about a 4-stroke 15hp?????

Indeed, it will probably be a nice motor after you finish it. I do like the quietness and silky-smooth idle when they're running right.
I agree, he replaced that impeller right before he ran it out of water for about 5 minutes and fried it....

will be interesting to see. i have had several 9.9/15 two strokes. they all ran nice and slow, low idle, lots of power and very quite for a 2 stroke. i have a 30hp on my 16 footer that runs amazing. no smoke, quite and smooth idle.

dino

 

[dkonrai]

Re: 1997 15 hp four stroke, new to me, first 4 stroke, pos

update,
omg i hate 4 strokes. so i put a water hose on the lower (have the lu off right now) and got water flowing to the ph. pulled the carb and gave it a good cleaning. changed the needle and seat. got it fired after some tinkering with the stupid top mounted mix screw.

it seems the fuel pump is bad. when i pull the rope i dont get fuel out of the hose to the carb. also it dies after a bit when you pump the hose, followed by, weak pump. i think that explains all the fuel that was in the oil. it will idle for a bit then die..... squeeze bulb, motor fires dies, etc..

now my vent, why are the carbs so complicated? why so much freakin plastic? primer works good, but it sucks that most of the primer is plastic. i guess it wont rot or rust. bowl, and top are all plastic.

ok vent is over. im still at a learning curve. now i look over the lovely classic 50's and smile. so simple in design. so light.

dino