1979 55hp running problems

[Jill_S]

We seem to be having problems keeping the motor running. Sometimes it will start right up and work fine then later it cranks but won't start. Carbs rebuilt (2) Also had problems of putting it in forward gear it would die but oddly enough it would do fine in reverse. Seems like hit or miss, intermittent. Gapless plugs don't appear to be flooded. Understand that at about 30% throttle is when the carb cam moves. We're not comfortably sure of control cable adjustments as we bought the controler separate from the motor and just hooked them up.

Some questions for starters. We believe we are correct that it uses a vented gas tank and it is vented. We pulled the line from the tank to the fuel pump and primed the bulb and it works, then checked outlet form fuel pump to carbs and it pumps good. We set the float in the carb according to specs with rebuild kit whis says 1/2 in full and 7/8 empty.

Starter sometimes does not engage fully and spins freely and understant this minor problem is unrelated to running problems naturally. So we'd like also to find a starter for this motor and have found the site Sea Way Marine has a supply of parts according to their site. Are there any other sites out there where we could find rebuilt or new starters, doubtful for new.

Thanks

 

[Frank Acampora]

Re: 1979 55hp running problems

Ah-Haa! Gapless plugs! Do you mean surface gap plugs? Champion UL18V or L20V? Do you have the Magna Power II ignition? It will say Magna Power on the engine somewhere, maybe the cover, and two coils will be mounted on the cylinder head. Depending on model, they may or may not be covered with an aluminum plate. If you do and you are having ignition problems, then there is not much you can do. That system was poorly designed and most eventually failed. Parts are not available for them. If you can find a used one, a retrofit kit was offered, but that was a long time ago-- I doubt you would be able to find a new one..
If you do not have Magna Power II system, do NOT use surface gap plugs. regular ignition systems do not have the power to fire them. Use Champion L4J if you have them. They are obsolete and nearest equivalent is NGK B8S or AC MK42FF or Autolite 2635.
For parts, check with Framzmarine over at Chrysler Crew. He has all kinds of "stuff".

 

[Jill_S]

Re: 1979 55hp running problems

Frank,
Thats not what I wanted to hear. Yes UL18V but can you put gapped plugs in.
It does say Magnapower near the electrical connections. It does have a poorly designed something mounted right next to the spark plugs so you have to remove them to pull the plugs.

OK so we worked until late and nailed some if not most of the of the problems.
Main issue was the adjustments of the control cables, idle adjust and the carb cam rod connecting thing. Sorry don't have the book to look up proper terminology. We set the control box in gear, pin in, and the control box lever to idle position, straight up. Then made sure the cable adjustment at the motor were properly adjusted for the idle position to the notched mark on the carb cam. Then we moved controller forward to full throttle. All looks good. Then moved lever back to idle but it stopped or rested a bit more advanced. So I took my hand at the motor and pushed on the cable toward the bow and it was at the correct position that we originally started in. Does any of that make sense?

So here is my next question. Are the control cables spring loaded inside somewhere? I'm a Johnson/Evinrude gal and when you move the throttle handle there is no hesitation, it instantly moves at the opposite end. I'm not talking about in the control box where you have to advance the throttle approx. 30% forward before it moves the motor parts, shafts and cams. It just seems like I can push on the cable at the point where it attaches to the motor linkage, inside wire of course, and it will move... say... a bit less than 1/2 inch with no affect at the remote controler up front. Maybe thats normal slack inside I suppose.

Gosh I hope this doesn't sound like jibberish but its hard to explain without eyes and pictures. We're getting really close. It starts right up, most of the time, put it in gear and doesn't die so we are ready to drop it in the water tomorrow for a real test run.

To be continued
Thanks Jill

 

[eurolarva]

Re: 1979 55hp running problems

I have a 45 HP that is about 10 years older then yours, however I had a similar experience as you. I was attempting to increase my idle by adjusting the cam on the attached picture. It worked like a champ except that when I would fish my motor kept flooding out on me and it would not start. If I pulled the plugs and let it sit for an hour it would fire up on the first try. The cam is an excentric. At idle according to the manual there should be enough room for a piece of paper between the cam and the carb throttle butterfly linkage. It is a tough adjustment to make but I found going minimum one sheet of paper was better then the cam touching causing a higher throttle. Hope this helps. It would be better for you to have a fuel issue then a spark issue. I looked your motor up at mercury and all the 79 models have the gapless plugs so you probably have the ignition that Frank mentioned.

 

[Jill_S]

Re: 1979 55hp running problems

Ahh!! Very interesting. I'm trying to make sense of your tip. Are you saying that if the cam is touching the carb throttle linkage that it may push on the carb linkage which messes with how the butterfly sits in the ...oh whats it called...the inlet throat for the air draft....something like that, causing it to flood. I really don't have to have an answer for that cause if it works then great. We'll check it out.

Now about those control cables. Its too wired how when all is set for idle and we move the throttle handle full, in gear but not running, how it does not come back to its original spot on the cam. Which we have it set looking just like your posted picture, advanced a bit from the notch mark. There seems to be play in the cables.

By the way, how do you post the pics. Do I have to have them out there somewhere on the internet for the forum to find.

I really appreciate the advice and tips from you folks. I am doing this for my brother in law and he is smart guy who works as a mechanic but is really dumbfounded with the boat motors. We are at wits end and I personally want to give up and find some kind person in California where we could take it to that won't charge us a small fortune. Or at least someone I could talk to on the phone. If anyone wants to volunteer and contact me we'd be very pleased. My e-mail is jschwocho@sbcglobal.net and I can give out my number there.

Thanks guys

 

[Frank Acampora]

Re: 1979 55hp running problems

The cables are a goofy system. If you look closely, you will note that the inner cable is attached to a solid point on the engine and a moving point in the control box. The outer cable cover is similarly attached to a solid point in the control box and a moving point at the engine. Logic would make it seem that no movement would be possible.
At any rate, there is compliance in the system and I can't tell you how many engines I have had that need the control handle backed into reverse a little then moved to neutral in order to actually get neutral. Sometimes its frustrating.
Oh, By the way: You do know that the throttle cable quick connect at the engine is spring loaded (it should be about twice the size of the shift cable quick connect.) and the center portion should be sticking out about 1/4 to 3/8 inch? This allows the shift linkage to move the engine into gear before the throttle starts to advance. If you don't have the tension on the internal spring, there will be more slack in the throttle cable which could cause your centering problem
The UL18V plugs are a very cold plug with an air gap in the ceramic portion. I don't think they make a gapped equivalent and if you go too hot---melted pistons (seems like everything you do wrong on outboards results in melted pistons).