115 Johnson 1973 115ESL73M no WOT

[Kloctower]

Last year I had an ignition coil fail so I decided that because everything on the motor was from 1973 and original I was just going to replace it all. I went to see the CDI website n ordered literally one of everything for my motor. It showed up I have the manual I am a paid mechanic in the automotive industry and do all the work on my four Outboards myself. I followed the manual to the T. changed out sensor coil, all four ignition coils, power pack, stator, electric choke, starter motor and selinoid, fuel pump, ignition key switch, I even upgraded to the CDI rectifier regulator instead of using an original version. After all that I set the timing according to the manual and the motor ran great for one time out it was perfect. (After the overheat event that prompted timing adjustment) The very next weekend I took the boat out and can't get wide open throttle. I thought maybe my timing set was off but according to the manual I'm supposed to synchronize carburetors and sensor coil or timing? I didn't see more about this in the manual I want to see what you guys think. I tried 3 different fuel tanks with larger hoses and new filters fresh Fuel and oil. Put the old fuel pump back on put the old rectifier back on try the old Power Pack and coils none of these things worked. Try adjusting the throttle cable that didn't seem to affect it at all. I did make one small adjustment to the timing between the time it worked and the time it didn't but it was like 1 degree. I set the timing with the prop off backed into my local launch because I thought it would be pretty hard to try to set it at 3900 RPM with a boat moving by myself LOL. If anyone has a better way to set timing I would love to try it. Now I don't even know if I could set the timing again because I don't think the motor will reach 3900 RPMs. Yes I torqued the prop down to its specifications. The motor does not overheat I can run it at half throttle as long as I want without any issues. For some reason it won't kick up on plane it stays at half throttle even though it should be at wide open throttle. Normally I can get close to 30 miles an hour out of this boat I can only get 10 right now. I did have one incident where the over temp alarm came on that is what prompted me to adjust the timing. After I replaced all the electronics on the motor I try it and got over temp alarm so I set the timing and have not had another over temp since then and the motor wasn't all that hot I shut it down immediately. Compression is good on all four cylinders. Spark plugs look good not fouled. I'm at a loss here don't know why I can't get wide open throttle with all new electronics. This motor ran great before I changed all the electronics and timing. I would go 15 miles out into Saginaw Bay on Lake Huron one-way fish all day

 

[jimmbo]

Timing is usually set/checked at cranking speed, or under load on a dyno. 3900 rpm under no load will be reached before the max timing advance is reached.
Whenever the carbs are off, or the linkages are disconnected, a check/adjustment of the carb-timing needs to be done
Are the carbs opening fully?

 

[Kloctower]

Thank you for your time. What do you mean exactly by "carb-timing" and how do I check or set that?

I forgot I should tell you the motor has been hard to start ever since I changed the timing. The first couple times out it was okay but now I have to crank is over for a good 2 or 3 minutes to get it started obviously I do it in intervals. I don't hold the key down that long. This motor was not hard starting before. It used to fire right up! Especially after already running that day.

Yes I believe the carbs are opening fully. I took it out yesterday and a friend was on the boat with me. He adjusted the throttle back and forth while I watch the motor and the carbs seemed to be operating normally. I will say when I had to adjust timing I did notice I had to move the spark Advance screw about a full inch and I thought that was odd. But I did have to install a new CDI sensor coil that's a one piece sealed deal instead of the old multi piece style sensor coil. It wasn't like the old sensor coil so I thought maybe that was why I had to adjust the stop screw so far. I have never taken the carbs off or the linkages off all the way. I have removed the mount-cover from over them to slide them out of the way but they were still connected to their points. I've only ever had to remove the cover that goes over the adjustment screws on either cable. I did have to remove both of the cables up at the control box when I replaced the key switch but that's pretty cut-and-dry no chance of messing up adjustment in the remote box up front...

So you believe my timing is in fact NOT set correctly? By removing my prop to set it I have made a mistake? Dang internet forum advice! Lol different forums than this one is where I got that idea. So I need to set timing again but at cranking speed this Time?

 

[racerone]

Are all the wires hooked up to the correct terminals on the powerpack ??----What are the actual compression numbers.----No idea why one would install all new electronics on that 73 model , not at all.----Timing normally is fixed at the factory and needs no adjustment.

 

[Kloctower]

Yes I double checked all the wires on all the power pack Terminals and the coils. Cleaned up all ground wires with sandpaper and made sure all spark plug connections were good and solid. Compression check was at the end of last year when the problem started I believe they were all around 110 or within a few PSI of there. Maybe I'll check again and let you know.

I REALLY appreciate your time and response so I don't mean to be rude here but why I changed the electronics on my motor is not relevant to what's wrong with it right now. Furthemore telling me that I shouldn't have done it doesn't help anything in any way shape or form. Someone else might start an argument over you making that comment. I'm not that type of person but I am going to point it out to you that it's kind of confrontational. It's almost like an insult. Kind of like telling me that what I did was stupid and I don't know what I'm doing. In my situation the wires were old and cracked and had copper showing in multiple places on different Electronics plus one of the coils failed so I made the decision to replace it all rather than waiting for another component to fail later on down the road possibly while I'm on the water. Electronics from 1973 aren't exactly the most reliable. I was also worried about Sparks jumping from Electronics to a ground or to one another causing problems. I had tape over some of them. I had the money so I decided it was time to just replace them all and I plan on rebuilding the power head if I have any further issues. I have already rebuilt the lower unit with all new kit and seals from top to bottom.
Now I hope I haven't offended you but it was kind of time wasted for me to explain all of that which is why I said it's not really relevant to the problem. Either way the electronics that came on the motor originally are gone and now they are all brand new and most definitely hooked up properly.

Also racerone as I said according to my manual after replacing the sensor coil you have to reset the timing. I was getting an over temp alarm and according to my manual it was due to timing. After changing the timing the over temp alarm went away but now I can't get wide open throttle as I could before.

 

[F_R]

So, has that motor overheated at some time in the past? It could have a water leak, spraying into the cylinders via the exhaust ports. Just a maybe-guess.

At any rate you need to find out if it is running on all 4. Do a cylinder drop test.

I don't think you could have the timing so far off as to have such a dramatic power loss.

 

[racerone]

Good luck with your project.

 

[Kloctower]

F r thanks for the reply. I'll do the test and check for water. I had one over temp alarm but i shut it down right away.

 

[Kloctower]

Good luck with your project.

Racer one you may not remember me but I certainly remember you. about a year ago you did this same thing to me in a different post. I let it go then but someone else pointed it out to you. It just seems like you're overly confrontational and some what condescending to some of the new posters on this form. I'm sure you're very knowledgeable but trying to stir the pot of doesn't help anything. If you're looking at this post objectively what you said was unnecessary and somewhat confrontational. It was insulting to tell me I don't need to do something I did when you're not here looking at my motor. Sorry if I hurt your feelings I didn't mean to but I'm just not going to let you continue to treat me like that. You don't have any idea what the condition of those Electronics worth so to tell me I don't need to replace them all without any more information is most definitely an insult. Again I'm sorry if I upset you or hurt your feelings but this isn't the first time you've done something like this to me I needed to point it out.

Last time you did the same thing you left the post in a huff after someone pointed out your rude comment. The components were damage and needed to be replaced. that means you were wrong. It's okay to admit when you're wrong and to apologize for insulting someone when you didn't have all the information. That's right now. if you would just apologize then we can move on instead of running off from the post because you were called out. I have no hard feelings against you I just don't feel it's fair for you to continue treating me like that when I try to be as respectful as possible.

 

[fireman57]

Did you ever clean/rebuild the carbs? The WOT could be the high speed jets clogged. The hard starting could be an issue from retiming it.

 

[Kloctower]

Fireman thanks for your answer. I haven't cleaned the carbs but I did considered the high-speed passages as a possible cause. It would just have to be incredible timing that the high-speed Jets get clogged up immediately after me changing out a bunch of electronics and resetting the timing. It could happen but I do run an inline fuel filter which has been changed every year and the tank on the boat is brand-new only 2 years old plastic with new pick up and lines. I bought this boat from a farmer's field it was a piece of junk I got it for two hundred bucks the motor started right up so I bought it. It had mice living in the engine cowling chewing on wires and such. The first time I fired it up and mice came running out from the air silencer. But the boat ran for 2 years just fine until the coil went bad I started changing things and now I have this problem. I changed out the fuel tank because it was rusted through and got all new lines cuz the old ones were so stiff. It's possible that the high-speed jets are clogged but they would have to be clogged by something left over by the mice that took two years to find its way into the carburetors. I keep the engine very clean now and as I said I've replaced pretty much everything on this motor. I don't really have the money to go out and buy a brand new boat so I slowly fix up my old one overtime now it's pretty nice.. for me anyway.

 

[Kloctower]

It's an old girl but it's mine. The minnkota terrova riptide 24v is worth more than the boat 2 times over! That and the Humminbird helix 9 SI make for a great time out fishing...

One thing I forgot to add is that I did drill into the right side of the motor to add a pisser. I bought the fittings from OMC and followed the post on this forum for adding the water discharge. It works great I don't think it has anything to do with my problem but that was something I did after changing All Electronics. I'm certain I didn't drill too far. Drilling and tapping holes is something I do on a daily basis at my job I'm very familiar with the process. As a matter of fact the drill bit that I used to pop the hole in the water jacket was shortened by me to make it impossible to drill too far...

I want to thank all of you for your replies. As of right now I'm going to reset the timing back to where it was from the factory and clean the carbs. I'm going to do the cylinder drop test and make sure my cables are set correctly with a link and sync and check all my work as far as wiring goes. After that I will get back to you but it will likely take some time. If you have any other ideas at to what my problem may be please let me know I'm all ears. I will make sure to update this Post as I work and also once I find the problem.

 

[Kloctower]

Things are getting worse now I'm beginning to think something else is wrong. I can't even get the engine to idle. I am attempting to do a Link and sync but can't make it through the process because the engine will not stay running. It will run great at times and idle high then all of a sudden it will just stall out of the blue.