1975 15 hp johnson leaking gas on its side

[OptsyEagle]

Re: 1975 15 hp johnson leaking gas on its side

If the primer bulb couldn't revive it, then I would not worry about fuel pumping for now. Verify the cylinder operation and let us know how that turns out.

 

[Johnson209]

Re: 1975 15 hp johnson leaking gas on its side

If the primer bulb couldn't revive it, then I would not worry about fuel pumping for now. Verify the cylinder operation and let us know how that turns out.

I checked each cylinder today and both are running ok I think. At first the bottom plug died when i did the test but I had it at the lowest idle. When I had the engine on higher throttle, both boots check out fine, neither died. I also took out the motor yesterday and it was worst then before. It would bog at first or sometimes dies when i try pushing it to full throttle. One of my buddy said my engine sounded like I have too much gas comming in and it was running too rich. I played with the adjustment and to no avail it sounded good and idles fine in the barrel, but when it's in the river it's a different motor.

 

[OptsyEagle]

Re: 1975 15 hp johnson leaking gas on its side

Well, a motor that bogs down is usually a cylinder cutting in and out. Perhaps the crankcase leak you had is coming back, only at the higher pressure that comes from higher RPMs. I can see it working until you hit a higher RPM and then blowing out the crankcase seal you made, but I would think this new leak would still be there later, at idle. I cannot see why it would re-seal itself back.

If I stay on the intermittant cylinder theory, perhaps a loose wire connection. A bad ground. A wobbly armature plate.

Also, what spark plugs are you using? Have we got you switched over to the NGK B7HS plugs? The champions do not work on that series of motor very well, and surging and bogging is one of a few symptoms they can produce.

Maybe some other people have some thoughts

 

[Johnson209]

Re: 1975 15 hp johnson leaking gas on its side

Thks optsy... I was playing with my motor last night switching the coils to see if I have intermittent sparks on my top coil and now the motors dead. It won't start. I put the coils back to it's original position and still won't start. I've took the flywheel off and check the points and they were about 19 so I reset them at .20. I have sparks jumping 3/4 or higher on the bottom but top plug is not jumping at all. When I swapt coils and clips I saw sparks jumping but the top one is still not jumping so I'm thinking both my coils are still good maybe my top condensers are fried .For sparkplugs I just put in some new ones they are Autolite 425. I don't see sparks plug being the problem
Because it still won't start with my old champion plugs. The last time i got the engine to crank over , it would bog and want to cut out so I tried high throttling it , but it did a couple burp and died and wouldn't start anymore. This motor never did this before. Do you think I have a bad reed or condensers.
My next thought is recleaning my carb again and reset the float to spec.Do you know the float settings on this motor?
I don't want to be buying parts I don't need, any ideas why it's acting up and not wanting to crank over when before it was idling good.I don't see any gas on my new spark plug when i check them but I can smell it though.

 

[OptsyEagle]

Re: 1975 15 hp johnson leaking gas on its side

If you are having problem getting a cylinder to spark, then that is the place I would focus. The condensers rarely fail. I would go back to your points. Give them a light filing with either a points file or some very fine sandpaper. Dip a white business card in some laquer thinner and pull it through the points and then blast them with compressed air. They should be very clean now. You can close the points and verify they have continuity with a multimeter before you put the flywheel back on. You can even put the flywheel on with a snug fit of the nut and do your external spark test to verify it is sparking well before you torque the flywheel on tight. Obviously you will just be pulling the starter rope and not starting the motor, with this test.

When you are playing around with spark plug boots and clips and you can't get the motor to start, you may find that you have switch the clips around. If the clips and boots are switched against each other you will be firing at bottom dead center instead of top dead center and the motor will never run. Check that (just switch the clips (not the boots) and see if it fires up or at least chugs).

I have never used autolite but I have used Champions and my motor will bog and surge. The best explaination for it is that in the series of motor you have, the fuel comes in to it in such a way that it can flood out that electrode. In later models, OMC designed the cylinder head a little different to avoid this, but you are stuck with the one you have. Myself and many others have had better success with the NGK spark plugs. It sounds weird to me, but I have proven it a few times myself, by switching between NGK B7HS and Champion UL81Cs. I used the NGKs for this reason. I can't say how the autolites work.

If you had a carb problem, it would effect both cylinders and most likely create issues at idle. I don't think your problem is in your carburetor. Could be reeds, but again, unlikely. If your reeds were defective, you can sometimes see fuel being spit out of the front of your carb barrels where your choke butterfly is. Sometimes it even shoots into the air silencer. Check that to be sure.

 

[Johnson209]

Re: 1975 15 hp johnson leaking gas on its side

Again Thks .. For all the information OpstyEagle. I'll try n switch the clips around and check for gas leaking in the air silencer for bad reeds. In the beginning of this forum I think I did mention that I lost a carb straw in the cylinder. Ive got more than half out but I don't know we're the rest went. I took off the side port n saw a piece in the reeds and got that out. But I couldn't see further in. Do you think I should take off my reeds and double check it our do you think whatever straw was left in it probably got burn out and came through the exhaust port. First I'll clean my points and follow yr steps.. Thks again

 

[OptsyEagle]

Re: 1975 15 hp johnson leaking gas on its side

I am not sure what you mean by a "carb straw". Was it a fuel tie like the one in this picture? In any event, in this picture you can see that this individual had a tie stuck in the reed, forcing it to stay open. As you may know a reed valve is designed so that on the upstroke of the piston it can suck fuel in, but on the downstroke it should close, forcing the fuel into the combustion chamber to be eventually sparked. If the valve is stuck open, the fuel gets forced out the reed and usually out the carb throat into your air silencer. It has pretty much the same effect as the crankcase leak you had earlier. So if you had something solid get sucked into the intake manifold of your motor, then take a very close look for this fuel spitting.

Unfortuneately, although some have said that one can access the intake manifold and reed assembly without removing the powerhead from the motor, I have never been successful at that. So, in my opinion, the powerhead would need to be removed to take a look at the reeds.

So check the other things first.

 

[Johnson209]

Re: 1975 15 hp johnson leaking gas on its side

I am not sure what you mean by a "carb straw". Was it a fuel tie like the one in this picture? In any event, in this picture you can see that this individual had a tie stuck in the reed, forcing it to stay open. As you may know a reed valve is designed so that on the upstroke of the piston it can suck fuel in, but on the downstroke it should close, forcing the fuel into the combustion chamber to be eventually sparked. If the valve is stuck open, the fuel gets forced out the reed and usually out the carb throat into your air silencer. It has pretty much the same effect as the crankcase leak you had earlier. So if you had something solid get sucked into the intake manifold of your motor, then take a very close look for this fuel spitting.

Unfortuneately, although some have said that one can access the intake manifold and reed assembly without removing the powerhead from the motor, I have never been successful at that. So, in my opinion, the powerhead would need to be removed to take a look at the reeds.

So check the other things first.

I was spraying inside my sparkplugs holes last weekend trying to clean the carbon deposit in the cylinder and the straw that came with the carb cleaner accidently flew inside the piston. It was chop up into 4 pieces. I got more then half out but the rest of the straw is left somewhere in the engine. When I open the side port of the engine to see if theres more pieces in there, there was a piece that was also lodge in the reeds but i taken that out. I check for leaks in the intake and there's no fuel spitting out. Somehow after Adjusting the points and cleaning them today the motor starts up and seems fine. It revs fine and idles ok in the barrel. I will take it out to the river this weekend and see how it runs. Usually it will run good in the barrel but when I'm on the water it's tottal different. I hope it will run as good as it did in the barrel .

Thks OpstyEagle ... I keep u updated

 

[Johnson209]

Re: 1975 15 hp johnson leaking gas on its side

Took the motor out today and it ran flawlessly . Who would think that cleaning the points and idjusting it back to spec would make the motor run as good as before. Two pull cold one pull warm. Idles all day long with no problems. I like to thank u again OpstyEagle and to all ya Fellows that help me also, thks.

 

[OptsyEagle]

Re: 1975 15 hp johnson leaking gas on its side

Good to hear. I usually tune mine up every couple of years, since the point blocks wear closing the gap a little over time. I reset them and of course clean them up and always notice a little more uhmff when I hit the throttle.

If you get a minute with a camera, I am sure a few on here would love to see a picture of your crankcase seal fix, if you can get the right lighting for it.

 

[Johnson209]

Re: 1975 15 hp johnson leaking gas on its side

Good to hear. I usually tune mine up every couple of years, since the point blocks wear closing the gap a little over time. I reset them and of course clean them up and always notice a little more uhmff when I hit the throttle.

If you get a minute with a camera, I am sure a few on here would love to see a picture of your crankcase seal fix, if you can get the right lighting for it.

Ok.. I will post up video ASAP when I get a chance to put my motor back in a barrel.

 

[Johnson209]

Re: 1975 15 hp johnson leaking gas on its side

If you get a minute with a camera, I am sure a few on here would love to see a picture of your crankcase seal fix, if you can get the right lighting for it.[/QUOTE]

heres a pics if any ones interested on seeing how I did it. Its a mess but i didnt get a chance to sand it down and paint it because Im still seeing if the marine tex would hold. So far so good.

Anyways i put new flooring 3/4 plywood on my boat and Im loosing mph. By myself before i was getting 20 mph. With 2 person 16 mph and with three I get 13 to 14 mph . What should i do when i carry a heavy load like three person. Should i change the prop in higher pitch or lower it so i can gain my speed back. Any thoughts guys? I dont have a tacho meter so i cant really test my motor. As of now i have the original prop on the motor. If i was to go a step higher in prop with heavy load on my boat do you think i would get my speed back.
thanks

 

[OptsyEagle]

Re: 1975 15 hp johnson leaking gas on its side

What hole do you have the tilt rod in? Counting from the boat, I tend to use number 2, when I am alone and number 3 hole when the boat is a little heavier. Obviously this all depends on the boat design and how the wieght is arranged in the boat. I know nothing about props. Always used the factory one they gave me.

Nice job on the seal. Thanks for the pic.

 

[Johnson209]

Re: 1975 15 hp johnson leaking gas on its side

What hole do you have the tilt rod in? Counting from the boat, I tend to use number 2, when I am alone and number 3 hole when the boat is a little heavier. Obviously this all depends on the boat design and how the wieght is arranged in the boat. I know nothing about props. Always used the factory one they gave me.

Nice job on the seal. Thanks for the pic.

Yeap no problem..
I have my tilt rod on number 2 when by myself and with people on board I put it on three..
Simetimes I hear the prop slipping though on three. You've been more then helpful OpstyEagle. I try posting up a new thread on the prop section n see if I can get a better idea bout getting a new prop. Thks A bunch..