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sometimes it starts, sometimes not! 1981 25hp

E

erratic_outboard

New member
I have a 1981 evinrude 25hp outboard, model e25rcIm which has run great for the past 10 years. But this year it only runs when it wants to. I’ve taken it out on the lake 4 times this year and the outboard will NOT start, despite me running it in a barrel the day before, each time. It runs great, low speed and full throttle, no fouling or stalling- and once I can get it started it’s good for the day. It doesn’t seem to want to start, it just turns over. I have to “fiddle” with it- pull the plugs (which look good) wipe them off, pull the cover off the fuel pump, etc, then eventually it will belch a little smoke and then start right up. This has never happened before, it’s always run like a trooper.

The engine has new NGK plugs, is getting gas, the fuel filter is clean, new fuel lines, strong deep cycle marine battery, and electric start. This model also has electronic ignition…

I took it out last Thursday and it would not start, despite me running it in the barrel at home the day before. So I pulled it out of the water and shined up all the electrical connections on the coils, etc, and dunked it again. Still no start.

Could it be bad coil(s)? I hate to start replacing parts that might be good, and we don’t have a good repair center here.

Please help- I’m not sure where to go from here and our boating season is short here in upstate NY!
Thank you!
 
Re: sometimes it starts, sometimes not!

Start by putting in Champion (Q)L77JC4 plugs.
Then disconnect the black/yellow cable going into the power-pack.
(Pull the pin out of the connector).
If this helps, you may just have a faulty stop switch.
 
Re: sometimes it starts, sometimes not!

Mine is doing that too. I believe the problem on mine is rain water getting into the ignition switch.
 
Re: sometimes it starts, sometimes not!

thanks guys, i am heading out to the driveway right now to try it again, and will post what happens later on the forum. watch, it will start right up and frustrate the bejeepers out of me!

stay tuned!
 
Re: sometimes it starts, sometimes not!

ok, i went out and tried to start it as is without doing anything, except for normal start procedure, and it would not start.

i pulled the power pack connector plug as mentioned above- no start. so i sprayed the 4 pin plug with electronics cleaner just to make sure, let it dry, plugged it back together, and no start.

the kill switch is dry, as i have it in the garage all summer so i don't have to take my gear out of the boat and cover it each time i take it out, so moisture can't be a problem.

so i continued to crank the motor, pretty much killing the battery but i had a charger on it. EVENTUALLY it coughed as i released the starter switch- at the end. this happened a few times. i tried it a few more times, then it belched some smoke and started. it acted like the choke was on for about 20 seconds, then cleared itself. it runs fine at full throttle and lowest speed and starts with just a touch of the start button, the way it used to. the way it should be. with no smoke after the initial start.

could it be that the gas is taking a long time to get to the cylinders for some reason? remember i installed new gas lines and the fuel filter is clean...

i did not gap the NGK spark plugs out of the package, just installed them. should the gap be .030? it runs so good, once i get it started, i don't think i need champion plugs. plugs are plugs, right? or am i missing something here? the NGK's cost me over 3 bucks apiece... not cheap.

and if i have to crank the thing so much at the lake the battery will probably die on me. not good for the starter either.

thanks for your help, very much appreciated!
 
Re: sometimes it starts, sometimes not!

I wonder if fuel is getting to the cylinders. I would put some fuel mix in a squirt bottle and spray some in the cylinders and carb. Then try to start and see if it will pop. If so, you could have a fuel delivery issue.
 
Re: sometimes it starts, sometimes not!

i just tried to start it again- no start. pulled the plugs and they have fuel on them so it can't be that. but i did squirt some fuel into the cylinders and the same thing- no start. it didn't even want to start, no sputtering, no nothing. I did change the plugs and used the new champion plugs (which were original for this engine) mentioned above and still got no start, no sputtering, just turned over normally.

so it appears to be a spark problem?

Any ideas? Bad coil(s)? and what is the purpose of the “power pack?” could that be bad?

i even tried to pull start it. i'll be feeling the pain tomorrow...

I’m at a loss here and really need some help.
Thank you!
 
Re: sometimes it starts, sometimes not!

When it acts up, you need to check for spark. Use either a spark tester or plugs themself is you don't have one.
 
Re: sometimes it starts, sometimes not!

Now, it’s a NO START all the time. I tried all day yesterday to get it started. I also checked the spark, the top cylinder has a healthy blue spark, there is NO SPARK in the bottom cylinder. They tell me this might be the power pack? is it possible that one of the coils burned out?

thanks again for your help!
 
Re: sometimes it starts, sometimes not!

Switch the coils, and you will find out.
But more likely a powerpack issue.
If you put in NGK plugs marked 'R', that might have been what killed the powerpack.
 
Re: sometimes it starts, sometimes not!

thank you for suggesting to switch the coils, can't do that today but hopefully i'll be able to get to it tomorrow and i will post what happens.

the NGK plugs are marked "B7HS" and below that "10"

the champion plugs are in the unit now.
 
Re: sometimes it starts, sometimes not!

i just ordered a power pack from this site, should be here early next week. i'll post what happens after i install it. seems to be the most likely cause of my problem. thanks everyone for your help!
 
Re: sometimes it starts, sometimes not!

i received the new power pack this morning, installed it, now i have NO spark on either cylinder. i'm really at a loss here. anyone have suggestions?
 
Re: sometimes it starts, sometimes not!

You need to get the OEM manual for your engine. It will help you troubleshoot your engine and make the necessary repairs to correct your problem.
As you have seen it is a waist of time and money throwing parts at your engine.
 
Re: sometimes it starts, sometimes not!

I don’t mean to be a pain by posting so many times but if someone else can benefit from my experience trying to fix this thing, then it’s worth it.

I reinstalled the old power pack, which previously provided spark on the upper cylinder, but this time no spark on either one. So I reinstalled the new power pack. Same result, no fire.

The diagnostic info that came with the new power pack states that for NO SPARK ON ANY CYLINDER:

-Disconnect the black/yellow wire from the power pack and test. If engine has spark, check the stop circuit. Thank you haffiman 37 for telling me to pull the pin out of the connector, I will try that when the rain moves out of the area and I can set it up in the barrel again.

-Disconnect the yellow wires from the rectifier and retest. If the engine now sparks, replace the rectifier.

-Then there is a bunch of technical testing that results in “the ignition coil(s) are likely bad.”

I know I need a service manual, but this should be a simple ignition problem, and I could do without spending $51.95 at this time. Plus the advice that you guys provide here is almost as good as a manual!

The parts diagrams provided on this site are not true explosions and do not show the true orientation of the parts of the assembly.

My question of the day is WHERE IS THE RECTIFIER? Is it under the flywheel?
 
Re: sometimes it starts, sometimes not!

hey bud take this for what it is, my question to you due to the simple fact that i know nothing about your engine as mine is an old johnson 9.5 , however my "no spark issue ended up simply being bad condensor and / or points and bad kill switch. now im not sure if your engine does have a point system or it is electronic but some people told me to replace my coils and after a new set of points i was sparkin like the fourth o july. now if youre not in a financial position to replace your entire ignition system . there may be some cheaper alternatives than just throwing a pile of new parts at this engine until it finally fixed. so heres my questions ;1) how are you checking spark..with a tester or using your plugs ? 2) does it have breaker points? 3) are they under the flywheel ? 4) have you inspected or tested the stop/kill switch ? now as i said i am a total newbie at boats and engines but have learned a wealth of information from this site and was able to fix by broken down old hoopty for less than $30 with everyones help from here and didnt need new coils . maybe i was just lucky but sooner or later youll be back out there and enjoying the water .good luck...dimitri
 
Re: sometimes it starts, sometimes not!

take a look at the first post on this thread, it gives info on my engine. 25hp 1981 evinrude w/electronic ignition (no points). electric start with strong marine battery.

i am checking the spark with the actual plug

no points, electronic ignition

i do need to check the kill switch, when the weather gets better. i store the boat in the garage in the summer but i can SEE better outside.

yes this site is great. i'm good with water and air cooled auto engines, but i've never worked on an outboard before, except for changing the plugs. the ignition system sure has some weird stuff in it.

so where is the rectifier? it might be under the flywheel?
 
Re: sometimes it starts, sometimes not!

i dont know where the rectifier is on your engine . perhaps since money is tight some one here can give you a link to a free manual or diagram of your ignition system . as far as checking for spark with your plugs, i was told that this would not work and you must use a spark tester. i got mine at the local auto parts store for $12 and it worked really well for me . apologies for running on about breaker points, as i said im new to this too . just a note ..after changing my points i still had no spark wich led me to a pile of troubleshooting that resulted in corroded and broken wires inside my kill swtch . simply taking it off and making sure the bare wires werent touching allowed me to check for spark and in turn fire up the engine..prehaps that storm will blow through and you can get back to mechanics....have a good day...dimitri
 
Re: sometimes it starts, sometimes not!

i pulled the black/yellow pin from the connector and still, no fire on either cylinder. so i guess that rules out the kill switch and circuit. my next best guess would be to test the rectifier. does anyone know where it is? i can't find anything visible that resembles the photos on this site. could it be under the flywheel?
 
Re: sometimes it starts, sometimes not!

Gee, about the only things left are the stator, timer base, or corroded connections.
 
Re: sometimes it starts, sometimes not!

agreed, i really should buy the manual. in the meantime, i gave up and brought it to a repair shop yesterday. i will post what they come up with- and the COST- when i get it back.
 
Re: sometimes it starts, sometimes not!

Just out of curiosity,did you clean all your ground connections?Sometimes a simple solution is the right one.
 
Re: sometimes it starts, sometimes not!

yessir i sure did, all connections are clean and good (except for pulling the flywheel) which is apparently where the rectifier is, my last guess of what the problem could be. the boat and motor has always been well taken care of, by me for the past 10 years and the previous owner for 8 years before me. that's why it's so frustrating. it SHOULD be something simple, it's a strong engine and has always run well.
 
Re: sometimes it starts, sometimes not!

Sometimes you cannot see the corrosion of wires.The battery cables are the worst.Moisture gets between the wire and sleve and corrodes the wire.The outside may look like new but the inside may only give you part conductivity,not enough to start,or none at all,depends on how the wind blows that day:)This can be said of many wires on a boat motor.
 
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Re: sometimes it starts, sometimes not!

The sad part is that this condition sometimes leads to other problems such as a bad starter,coil problems and wires that melt and ground out.I all goes well.
 
Re: sometimes it starts, sometimes not!

mixd you were right- the shop found rotted wires in the coil circuit downstream from the new powerpack that i installed. so i probably did not need the new PP anyway. in addition, the neutral start switch is defective- i went around that and grounded the wire, which now enables the motor to start, but it will start when it is in gear, not good. i just need to remember to always start it in neutral. the engine starts and runs great everytime now, and i need to order a new neutral start switch.

thank you and everyone who helped me with this problem on this forum. also kudos to WAYNE AND CHRIS AT LEWIS MARINE, FORT COVINGTON, NY for their help in solving this problem.

i am looking forward to getting out on the water and catching the "big one" when the weather turns a little cooler!
 
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