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Johnson 25 HP wont start

R

Robert Floyd

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I have a 25hp seahorse that wi

I have a 25hp seahorse that will not start. The model number is 25502B. What should I check?
 
"1975 25hp Evinrude. When was

"1975 25hp Evinrude. When was the last time it ran normally?

Check the compression, what is it?

With the s/plugs removed, the spark should jump a 1/4" gap with a strong blue lightning like flame, a real SNAP! Does it?"
 
"I bought the engine and boat

"I bought the engine and boat from a guy. He said that it runs good. He also gave me a receipt where he had the engine rebuilt last summer. I think I figured out the problem I just need to know how to set the fuel mixture. The guy had disconnected the mixture adjust knob on the front of the motor, and my daughter moved the big needle on the top of the caRB."
 
"(Carburetor Adjustment -

"(Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)

Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.

Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

Note: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor. It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing this final adjustment due to the fact that one of the valves might be initially set ever so slightly lean.

When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.

http://stores.ebay.com/Evinrude-Johnson-Outboard-Parts-etc?refid=store"
 
is there any way i can do this

is there any way i can do this in my driveway or do i have to go to the lake?
 
"Robert,

What you need is a

"Robert,

What you need is a tank(trash can, or simalar), make sure you get enough water in it to cover the water intake ports. Run your motor, make your adjustments. You'll see surplus oil floating in the tank, this normal, and can be scooped out after testing is complete and before dumping the tank water. I leave my motor hooked up to my boat and slip tank, in my case a trash can,under motor(tilting motor). Works Great, just keep enough water in there to keep motor cool. You'll loose some water due to splashing."
 
"ok I got it to start but I ca

"ok I got it to start but I can not keep it running, and when it died last time I could not get it to restart. Please help I need this thing running by thursday."
 
"and if it matters any, it was

"and if it matters any, it was also smoking real bad. when it was running."
 
"Smoke eh?

Compression was

"Smoke eh?

Compression was what?
Good spark?
50:1 fuel mix?
Plugs looked like, before, after it ran?
It's getting fuel to where, fuel pump, carb, cylinder?
Carb set per Joe's spec's?

If it is just a matter of adjusting the carb, these adjustments as Joe describes, done correctly does work. The first 1-1/2 turn is close enough to get it to run, unless the idle(rpms) is set too low. Once you find the place where it will run on the idle screw, the rest of the adjustments are fine tuning, and need to made carefully and slowly, so wait 15 seconds or so in between movements to let the motor catch up to what you're doing. Some smoke when you run in a tank is ok, but if it smokes while you're out on the lake is a different thing. Set your carb, and I think it probabaly just needs to be run for awhile to blow out the cobb webs."
 
"took it tto a shop and they c

"took it tto a shop and they checked everything out and said that it isnt worth fixing. The flywheel key is sheared, armature plate has a lot of play in it, crank seal is leaking, oil and gas all over points and condensor, broken motor mount on bottom front(not available anymore), has a rough spot when turning it over. They dont know if the last one is in the powerhead bearings or the lower unit."
 
"Take the lower unit off and t

"Take the lower unit off and try it.The flywheel key sheared is not expensive nor is the seal replacement ( can be replaced in 10 minutes )The motor mount should be plentifull used. Sounds to me that you need a manual ,take it all apart and then see if it is worth assembling.sounds like a good winter project.Used parts for that motor are plentifull to say the least."
 
that is what i was thinking. b

that is what i was thinking. but what about the armature plate?
 
That motor was basically the s

That motor was basically the same for many ( 20 ) years.Used parts are plentifull. I have several
apart in boxes.
 
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