# 15 HP Evinrude help - No power or rpms



## wmk0002 (Jun 20, 2016)

I posted about this motor on another forum so I am copying and posting that original post here below:

I have a relatively new to me 1982 Evinrude 15HP, model E15RCNC. I bought it based off having good compression and that the seller ran it in a barrel at low speed on top of a good price. Since I have bought it, I have checked the impeller and LU oil and both are in good shape and the motor is cooling. I rechecked compression and got 110 psi on both cylinders. I installed a helicoil into the stripped recoil starter hole and now don’t have to use a rope on the flywheel. I checked spark and both are jumping a ½” air gap on my spark tester.

The first time I tried it out on the lake I was in a 1436 flatbottom. I had previously just ran an old Sportwin 9.5 hp and got a decent 16 mph out of it on the boat so figured this one would do much better. First blast off it took off with good power and immediately bogged down to just a few mph. Back home in the barrel I rechecked everything I did prior and after convincing myself it was good I gave it another lake test on my new 1648 Alumacraft flatbottom. Same bogging, lack of power, and slow speed/low rpms as before. FWIW the Sportwin did 15mph on this hull.

This time, I rebuilt the carb. The old one was clean but the needle was sticking some. Lake tested again and got the same results. This test though I tried pulling plug wires. Pulled one plug wire and ran the motor and it ran like when both were plugged in…so I thought it might have dropped a cylinder. But then flipped it and it still ran, just slightly worse. So both cylinders are firing.

On to working on it again in a barrel at home, I pull the plug wires while it’s running at a somewhat fast neutral idle and have the same results as on the water however I notice massive arcing from the disconnected coil to the block and other coil. It does this when either plug is disconnected. Is this a sure fire indicator the coils are bad? Or should that be expected when they have such a high charge and nowhere to dissipate the energy to?

I will add I have not installed new plugs yet. They are the correct ones though in that they are Champion QL77JC4. Neither looks totally fouled although one does have some white spots on it. I know I have compression, spark (at least to the plugs), and fuel (I’m confident in my carb rebuild as I was very thorough). In all of my tests I tried pumping the primer bulb but to no avail, gas was fresh and properly mixed, and vent cap open. Does this seem like fouled spark plugs? Or does the coil arcing I mentioned indicate something else? I am buying new plugs today and ordering new plug wires too. I’m looking for advice as to what the problem may be and what to try next if new plugs and wires don’t do the trick. I definitely don’t want to go throwing money at the ignition system until I know for sure what is at fault in it, if anything.


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## wmk0002 (Jun 20, 2016)

I bought some new Champion L77JC4 plugs today. I also bought some of the sprayable Seafoam Deep Creep to use on a on the water test to see if fuel starvation is an issue here.


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## dahut (Jun 20, 2016)

You're pretty thoroughness I'll give you that!
I have to question any coil that is arcing to the surrounding structures

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## wmk0002 (Jun 20, 2016)

dahut said:


> You're pretty thoroughness I'll give you that!
> I have to question any coil that is arcing to the surrounding structures
> 
> Sent from my LGL31L using Tapatalk



Thanks lol. I try to tell the whole story up front. I'm pretty competent when it comes to outboards but electrical/ignition problems frustrate me to no end and I'm fairly sure that's my problem. I'm confident fuel delivery is not the issue and compression is what it is. 

I question arcing coils as well because they are supposed to be isolated aside from the high tension spark plug leads. I'm not familiar with this motor nor its coils but imo the hardened resin/epoxy or whatever it is that they seal them with feels almost tacky on both coils instead of smooth. Seems strange for both of them to be this way though if it is a problem.


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## perchjerker (Jun 20, 2016)

I would replace that coil for sure

it probably has carbon tracking and you are losing spark though it under load. 

I would be inclined to replace both coils And the plug wires as well since you are in there.


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## dahut (Jun 20, 2016)

I can't see how it can be much else, with all the diligence you've put in.

I'd follow Mr. Perchjerkers advice

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## wmk0002 (Jun 21, 2016)

I think I will do that. 

Does anyone have a brand recommendation? The OEM, CDI Electronics, and Sierra brand coils are all priced very similarly for this motor.


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## perchjerker (Jun 21, 2016)

OEM all the way

the old one lasted, what 34 years? (unless it has been replaced before of course)


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## dahut (Jun 21, 2016)

Got a link to them?

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## wmk0002 (Jun 21, 2016)

Here's a ling to the ignition system parts list. The coils are number 3. 
https://www.marineengine.com/parts/...E15RCNC&manufacturer=Evinrude&section=Magneto

I also tend to lean towards the OEM ones, but I seem to recall reading somewhere that CDI Electronics makes superior parts....but I could easily be wrong on that.


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## dahut (Jun 21, 2016)

Thank you for providing the link.
Would you undertake to explain the "power pack" shown in the parts breakdown.
I'm thinking "exciter" or pilot coil, but I haven't done that research.

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## wmk0002 (Jun 21, 2016)

From what I remember from the service manual, the power pack sends out about 200-300V to the coil (as powered by the stator, and signaled from the trigger/timing sensor). The coil then supercharges that to multiple thousands of volts to make a good spark under compression. To my knowledge, if the powerpack fails, you totally lose spark to one or more cylinders either all the time, sporadically, or after the powerpack gets hot and fails/shorts. I had this problem on my 70hp...it would drop a cylinder after running for a few min when the powerpack began to heat up. Costly fix as it was about a $250 part if I remember right.

I'm not losing any spark from what I can tell so I think the powerpack is ok. I do have an inductive timing light I can use on the water which can help me verify if it comes to that. I also have a 9.9hp which has a compatible pack I can swap over to this motor and test. Actually I would try that with the coils too, however, despite being the same model year motor, it has the older style rounded coils for whatever reason.

Hope my powerpack explanation makes sense. I can read up on better from my service manual when I get home.


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## dahut (Jun 21, 2016)

Yes you explained what I'm referring to as a "pilot coil" very well.

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## wmk0002 (Jun 22, 2016)

I captured some video for yall just a little bit ago. 

https://www.youtube.com/watch?v=qMg2AfyNkrU

I ran the motor at a fast idle and pulled each plug separately. As you can see, each coil arcs to the engine block and occasionally to the other coil as well. Looking more closely (and seen in the picture below) the back portion of the coil that contains what I call insulating resin (?) is not just tacky like I previously mentioned but actually mushes when I press on it hard. Also, only one coil has a part number on it but from what I can tell that part number is for a 5 and 6 hp motor. Maybe this motor had the wrong coils and they have been damaged by seeing too much voltage from the powerpack than they are built for? I don't really know, however, I think my best bet here is to buy 2 new OEM coil kits. That way I know that the coils, wires, and plugs are new and not the cause of my headache.

I'm about to look through my service manual one last time to see if there are any more tests I can perform before ordering though. I have a DVA adapter for my multimeter so I should hopefully be able to verify that at least the ignition system up to the powerpack is working correctly by outputting the correct voltage range.

Pics:


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## dahut (Jun 22, 2016)

Wow you are thorough.
I like that.

I'm calling you if I ever need help with an outboard engine!

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## wmk0002 (Jun 22, 2016)

Thanks, but let's see if I can get this one fixed first lol! Fingers crossed new coils, plug wires, and plugs will do the trick.


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## dahut (Jun 22, 2016)

:thumbs up:

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## perchjerker (Jun 23, 2016)

those coils are definitely shot. 

replace everything like you are planning

just an fyi it takes more spark to fire a cylinder that is under load than it does at light load or idle

so its leaking spark though those carbon track when you are running it


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## wmk0002 (Jun 23, 2016)

perchjerker said:


> those coils are definitely shot.
> 
> replace everything like you are planning
> 
> ...



Thanks for the vote of confidence perchjerker.


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## dahut (Jun 23, 2016)

:thumbs up:
You had me at widespread arcing, the wrong type coils, and potting compound tturned to soft mush

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## wmk0002 (Jun 23, 2016)

Ordered some OEM coil kits that come with new plug wires just a little while ago. Hopefully get them in and installed early next week. I'll post an update on everything then. Thanks for the help guys.


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## RiverLife (Jun 27, 2016)

I would be checking the exhaust ports first before ordering any parts. If they are built up with carbon it wont rev up or have any power.

Good job on the carb rebuild and compression check. Now you have a good baseline down. I would also change the plugs and make sure gap is correct. How about fuel filter?

Coils work or they don't generally or may cut out when engine gets hot. You described more of a bogging rather than miss firing. I feel coils are ok.

You can try starting engine in the dark to see if wires are arching out. Bad wires will also be a misfire and not a bogging condition.

My guts tell me to check exhaust on this one. 

Color of spark plugs tell a story. What color are they?


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## wmk0002 (Jun 27, 2016)

Well.... coils came in amazingly fast getting here Saturday. Ordered them from MarineEngine.com btw. So Saturday I installed the new coils, plug wires, and plugs(gapped to 0.030"). Then Sunday took it to a small local lake for a test run and had no real noticeable improvement. I installed a new inductive tach and using my phone's gps was seeing max speed of 7 mph at max rpms of 3100. While out I verified that the butterfly was fully opening, that fuel was flowing through my clear fuel line between the pump and carb, and that it was pumping good water and cooling. I brought a can of the the Seafoam Deep Creep and gave it a few quick squirts to see if it responded like it was starved for fuel but it didn't help. Then I gave it some longer blasts like you would do for a decarb for kicks and it bogged worse and smoked a ton but then came back up to the same rpms as before.

I'm going to revisit my spark and compression test again along with pull the flywheel to check the ignition components under it and to check the shear key. I'm not sure what ignition problem would contribute to this now. I know the charge coil under the flywheel typically has a high speed and low speed output so maybe its possible the high speed side is bad but I can rev the motor up much higher in neutral in a barrel with out any cutting out. Maybe the spark can keep up but gets weaker at that speed?

But Rivelife may be on to something. At this point, if there was a serious ignition problem I think I would be seeing some different symptoms. This motor does have some nasty goo coming out of the exhaust leg and thru hub exhaust ports when I run it on muffs or in a barrel. Stuff looks like light gray grease. Can I pull the exhaust port cover and inspect or will I need to totally pull the powerhead?


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## wmk0002 (Jun 27, 2016)

To address a couple other points Riverlife mentioned, I have not messed with the fuel pump or it's filter. I have totally forgot the fact that the fuel pump diaphragm could be leaking and flooding one cylinder. I will check that.

As to color of the plugs, both are very wet with fuel. No water that I can tell. Seems like more fuel is being delivered than can be burnt.

I'll pull the plugs this evening and post pics. Also post some better pictures of my old coils. Even if they were still good, I'm glad I changed them because they looked rough.


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## RiverLife (Jun 27, 2016)

Man I have worked on more motors than I care to admit. 

By what your telling me now it's time for a new carb. I have pulled my hair our with similar problems recently with a 15hp Mercury. I would run it in a barrel and it would muck up the water and pump fuel out the exhaust. Plugs were soaked. I rebuild carb and fuel pump and it was worse. 

Sometimes carbs won't atomize fuel any longer and need replaced. The Merc 15 starts on one pull idles nice and runs good now with new carb.

Make sure lower unit does not have any fishing line around it and that it spins free and lube is good.

Have confidence in yourself and you will figure it out. Keep at it and keep us posted.


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## wmk0002 (Jun 27, 2016)

RiverLife said:


> Man I have worked on more motors than I care to admit.
> 
> By what your telling me now it's time for a new carb. I have pulled my hair our with similar problems recently with a 15hp Mercury. I would run it in a barrel and it would muck up the water and pump fuel out the exhaust. Plugs were soaked. I rebuild carb and fuel pump and it was worse.
> 
> ...



I'll look into it. I didn't know a carb could really go bad though. I have a 9.9hp of the same year I just made some progress on but have yet to try out. If it performs well I can do a carb swap between the two and see what happens on each.


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## kofkorn (Jun 27, 2016)

Pull the carb and look at the float. Not sure when the change happened, but they went from a cork float to a plastic one. The old cork floats can sometimes get "Waterlogged' and will sit lower in the fuel than they should. It causes the fuel level to run higher than it should and can cause a rich condition at open throttle. You don't usually notice it at idle because you adjust for it with the low speed needle. I bought a motor that had this condition. It would run poorly and occasionally stall at WOT. I changed out the float and it ran like new. 

Every time I open an carb and see the cork floats, I replace them with a new plastic one. It's not worth the chance.

Good luck!


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## perchjerker (Jun 27, 2016)

even though the coil did not fix it you did the right thing to replace them


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## wmk0002 (Jun 27, 2016)

kofkorn said:


> Pull the carb and look at the float. Not sure when the change happened, but they went from a cork float to a plastic one. The old cork floats can sometimes get "Waterlogged' and will sit lower in the fuel than they should. It causes the fuel level to run higher than it should and can cause a rich condition at open throttle. You don't usually notice it at idle because you adjust for it with the low speed needle. I bought a motor that had this condition. It would run poorly and occasionally stall at WOT. I changed out the float and it ran like new.
> 
> Every time I open an carb and see the cork floats, I replace them with a new plastic one. It's not worth the chance.
> 
> Good luck!



I replaced the old float with the new one that came in the OEM carb kit. I adjusted it to level when turned upside and blew through the fuel inlet with everything I had but couldn't get it to blow through. So I'm pretty sure my float and its setting is good. I also have new fuel hose so I should be debris free withing the fuel system. Probably need to add a filter to the fuel tank hose and check the screen on the fuel pump though.

I'm glad I changed the coils too. If I end up just using my 9.9 hp, I will swap coils so the one I'm running has the most up to date ones so it definitely wont be waste.


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## wmk0002 (Jun 29, 2016)

Copy and pasted below is my post from the iboats forum. The high speed jet test was done per a rec on there.
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Here is what I did last night. I removed the carb to check out the high speed jet. It was really hard to read but I'm almost certain it said "58 15". My guess is that means it is a 0.058" size jet for a 15 hp? When I tried researching what 15 hp took that size of jet I got a hit for a 2000 model 15hp. Based on my searching through the parts diagram for my motor, I should have a size 56 jet. Aside from the jet, I checked the entire carb out again. It was really clean, full of fuel, and the vent was clear. The needle valve was seating fully when I inverted the carb and it wasn't sticking. I put it all back together and moved on to some more tests.

Next I pulled the plugs. The top cylinder's one was pretty clean and the bottom's was dirty. With the Seafoam Deep Creep I was spraying in it on my last water test I would think both would be really clean if the spark was as it should be. So then I did another spark test and both plug leads were jumping a half inch gap like before. I then put the plugs back in and ran the motor while attempting to use my multimeter to measure the voltage on the leads going to each coil. According to the troubleshooting guide I saw they should both have 150V no mater the rpms, but should increase with rpms up to 300-400V. For whatever reason my multimeter wasn't working but in probing the wires the voltage was arcing up my test leads and to the block and killing that cylinder. I tried it again closer to the powerpack and this time it died and I also lost all spark. Not really sure what happened...I know it is not a kill switch problem because the black kill wire from the pack is taped off and I kill the motor by just backing the throttle all of the way off.







A note I would like to add is that when I first fired the motor up (cold start) I manually pushed the cam roller to give it some gas and rev it up. When doing this, for the first 10-15 seconds, the motor ran smoother than it typically does and the throttle response was almost immediate like lit should be. But as soon as it warmed up just a little it went back to feeling like it was maybe missing and bogging when I quickly gave it throttle.


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## wmk0002 (Jun 29, 2016)

After getting bummed out with my work on the 15hp, I removed the LU from it and installed it on my 9.9 for the first time since cutting the water tube to convert it from long to short shaft. I ran it in a barrel and it ran pretty good. So after work today I think I will take it to the lake for a test run on my boat to see how it performs. If it does ok, I think I will drop in the 15hp carb and give it another test. If that works too, I can basically rule out the carb on the 15hp. I can take it from there and maybe try a powerpack swap, fuel pump swap, etc and maybe narrow it down further that way.


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## wmk0002 (Jun 29, 2016)

Also, FWIW, this is what the bottom of the exhaust leg looked like after I pulled the LU. Is the gray, foamy exhaust a sign of anything in particular? Seems like it would be caused by a lot of unburnt oil. Also, why is the main exhaust tube exit so resitricted? It appears there is a larger hole above the two smaller ones that has a piece plugging it up. Is that correct way everything should be?


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## kofkorn (Jun 29, 2016)

The two different spark plugs is concerning. You may have a head gasket leak, letting water into the cylinder with the clean plug. Can you shine your flashlight inside the cylinder and see any water droplets after running a few minutes? If you have one cylinder that is sparkly clean as compared to the other, it is usually an indication of water intrusion.

A gray foamy mix could also mean you're running rich. The gray foam is the emulsified fuel/oil combo that mixes with the water coming out of the exhaust. It's usually an indicator of a carburetor issue. I'd check your float level again. Also make sure that the gasket isn't extruding into the carburetor space. Sometimes if the gasket isn't positioned properly, the float can get hung up on the gasket, preventing it from fully seating. 

An easy way to test this is to take your boat out and get it running. Warm it up and get it going as fast as it currently can. Then go back to idle, disconnect the fuel line and immediately go back to WOT. If you have a fuel level issue, the motor will run slow for a few seconds and then as the fuel level in the bowl drops, the motor will gradually speed up to a normal high speed WOT, before eventually stalling from lack of fuel. (Don't try this with a multi-carbed engine, you could starve your top cylinder before the bottom one runs out of fuel)

Hopefully this will eliminate any worries of an electrical issue. 

Good luck!


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## Sinkingfast (Jun 29, 2016)

About that exhaust restriction...

When I rebuilt my 76' 15hp I did away with the wet leg and installed the megaphone exhaust. When i did some research..like 2 years on that motor..I saw that the megaphone mids had various versions of that outlet. Some had 3 holes, others 3 holes with one plugged..and with just those 2 holes and no 3rd hole or plug. Even saw one on ebay with a nut and bolt in that large 3rd hole. Ebay is good for more than buying..


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## wmk0002 (Jun 30, 2016)

I appreciate all of the help guys!

I do have some good news in that I tested my 9.9 out yesterday evening and it worked really well. I'll shy away from great as it could probably use a tuneup itself but it started easy, idled decent just not down very low, and got up to WOT with no hesitation or misses. It pushed my boat 16 mph at about 5100 rpms with just me in the boat and did 14-15 mph at 4900 rpms with my dad in the boat with me. This was done with a decent shape standard 10" prop. According to the prop calculator I used those rpms and speeds indicate a lot of prop slip (19-25%) but I guess that is expected with a smaller motor and a big boat as it doesn't really seem to get fully on plane so it has extra drag. As a side question, would this motor on this boat be best paired with a 9" prop and would a 4 blade, if available in that small of a size, allow better "grip" which may reduce my prop slip and help my speed/rpms a little?

So now with a running 9.9 motor, now I can start doing some carb swaps. I think I will drop the 15 hp carb on the 9.9 next and give it another try. If it runs well and I see the expected rpm gains then I'll know I can rule it out. If not I can try the advice to disconnect the fuel and see if it picks up rpms as the fuel bowl level begins to lower which would indicate an improper float height. Likewise if the carb seems to be the issue, I can then later put the 9.9 carb on the 15 to see if it performs similarly to the 9.9 or if possibly has other issues.

In addition to the carb, both the fuel pump and powerpack will be easy swaps as well if it comes to that. So I feel I am in a good position now going forward....plus I have a working motor I can use in the meantime which is huge.


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## wmk0002 (Jul 11, 2016)

Just got back from from vacation so haven't done any fiddling with the 15 hp recently. But I did take the boat out with the 9.9 hp again the day before I left. This time I took some Seafoam deep creep with me plus installed the newer plugs I had previously put in the 15. This trip out, after running it hard and doing a halfway decarb with the deep creep, I was seeing 5400 rpms by myself and was just shy of 17 mph. 

I think I am confident enough now with this motor that I will try the 15 hp carb on it next.


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## wmk0002 (Jul 14, 2016)

Put the 15hp carb on the 9.9 hp the other day and ran it in a barrel yesterday. Ran great in the barrel so I plan on giving it a lake test this weekend. I'll post back with results and I'll try to shoot a video as well.


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## wmk0002 (Jul 16, 2016)

I was able to take the boat out this morning for some fishing and to try out the 9.9hp with the 15hp carb. It ran almost identical to when the 9.9 carb was on and ran well. I only saw a couple hundred more rpms up to 5600 and maybe 0.5-1 mph gain but it still ran good so I guess that at least proves that the 15hp carb is good and isn't the source of my 15hp lacking power. I forgot to take the 15hp fuel pump with me to try that out but will do that next. I'm making some progress here at least.

And if anyone has any ideas why I didn't see the expected rpm gains from the 15 hp carb I'd like to hear them. I know im missing the reed spacers and tuned exhaust tube to go the full way to the 15 hp but I thought the carb alone would do more. Is it still possible the carb has a minor issue like the jet possibly being the wrong one? In a previous post I mentioned I thought it was a jet from a more modern 15hp carb and was a couple thousandths larger than what it should be. I'm certain the throttle plate was fully opening at WOT too.


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## perchjerker (Jul 17, 2016)

dont dismiss the need of the reed valve spacers and exhaust tube. The motor needs to breathe properly with the different carb so you may not see much difference without them. 

I dont have any direct experience with this motor but was an automotive mechanic most of my life and I can tell you to maximize performance of an engine (which is basically an air pump) all the components must be in place for maximum output from the setup


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## Pappy (Jul 17, 2016)

wmk0002 said:


> I was able to take the boat out this morning for some fishing and to try out the 9.9hp with the 15hp carb. It ran almost identical to when the 9.9 carb was on and ran well. I only saw a couple hundred more rpms up to 5600 and maybe 0.5-1 mph gain but it still ran good so I guess that at least proves that the 15hp carb is good and isn't the source of my 15hp lacking power. I forgot to take the 15hp fuel pump with me to try that out but will do that next. I'm making some progress here at least.
> 
> And if anyone has any ideas why I didn't see the expected rpm gains from the 15 hp carb I'd like to hear them. I know im missing the reed spacers and tuned exhaust tube to go the full way to the 15 hp but I thought the carb alone would do more. Is it still possible the carb has a minor issue like the jet possibly being the wrong one? In a previous post I mentioned I thought it was a jet from a more modern 15hp carb and was a couple thousandths larger than what it should be. I'm certain the throttle plate was fully opening at WOT too.



Perchjerker has nailed it perfectly. 
The carb is only part of the upgrade. You have now modified the front end of the "air pump" but cannot properly get the benefit of opening up the intake side without modifying the exhaust to take advantage of it. The side benefit here is that, once you pull the powerhead you can also get new water tube grommets and replace the old and probably restrictive ones and replace all your fuel lines while you are there.


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## wmk0002 (Jul 18, 2016)

Thanks for the info and reassurance guys. I will definitely do the full conversion later on, not just the carb.

As of now, I'm moving back to trying to get the 15hp going. At least if I get that running right I can run it on my hull and know for sure how a 15hp should really perform on it.

Speaking of the 15hp, yesterday I tried to remove the flywheel to check everything out under there but was left hanging as my puller kit didn't have bolts that would fit in the smaller holes. So I visually checked out the exhaust passage on the leg and it looked good. Then rechecked cold compression and got about 108 psi on each cylinder. I still need to check the fuel pump condition but aside from that my next priority is going to get some grade 8 bolts to pull the flywheel with.


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## wmk0002 (Nov 9, 2016)

It has been a while since I fooled with this motor but finally figured out why I mysteriously lost spark. Turns out the powerpack died on me. Swapped it out with the one off of my 9.9hp and I now have thick spark jumping a 1/2" gap.

Is it possible a failing powerpack could have been my problem all along? Possibly somehow weakening the spark as rpms went up? I know they are the brains of the ignition system but not sure what all symptoms a failing one can cause.


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## wmk0002 (May 18, 2017)

Finally ran the motor with the known good powerpack in a barrel and it ran well. I will boat test it sometime in the next few days and report back.


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## wmk0002 (Jun 1, 2017)

Victory at last!

I lake tested the motor yesterday after work and it opened up wide open and climbed to WOT rpms. I saw 17 mph but didn't have my tach on to get rpm readings. This was with the 9.9 hp carb on it so my speed is right on par with what the 9.9 hp motor was producing on this boat.

To recap what I did... I changed the plugs, installed new OEM coils and plug wires, and put on a known good powerpack. Based on no performance changes from the new plugs, wires, and coils I would say that I had a bad powerpack all along. Based on the unburnt fuel on the lower plug, it seemed to be failing at higher speed and producing very weak to no spark on the bottom cylinder. Whatever was causing this problem eventually totally failed when the powerpack died altogether.

Now I just need to order a new/used powerpack and put the 15hp carb back on and this motor should be good to go for another 35 years lol.

I appreciate the help from everyone!


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## finstr (Jun 1, 2017)

Congrats on finding your problem. I just found this thread and was thinking as I'm reading the issues that the power pack unit you describe sounds remarkably like an ignition module from an automobile. They're responsible for not only firing the coils but firing them at the correct time. The ignition advance curve is programmed into them and sometimes as in your case the ignition won't advance thus creating a serious lack of power and rpm. And they are impossible to bench test. I'm not sure if it's possible to run a timing light on an outboard even to check maximum advance. Like a lot of automotive manuals will state..."Replace with known good part" lol. I love that.

PS. It's very possible that the arcing coils damaged the unit. I've seen that many times in the automotive field.


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## Stumpalump (Jun 2, 2017)

That vintage power pack biodegrades. Changed one on the advise of seaway marine when I tuned up an 83 that ran poorly. Johnson and Evenrude dropped the price of the units to drown out the cheap China knockoffs. I think the bad coil issue was for the older stuff but people always swap coils first because it's a no brainier. On 80's OMC the power packs are a known biodegrade issue. I'm buying a 6hp today that does not run. Wish me luck.


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## wmk0002 (Jun 2, 2017)

Stumpalump said:


> That vintage power pack biodegrades. Changed one on the advise of seaway marine when I tuned up an 83 that ran poorly. Johnson and Evenrude dropped the price of the units to drown out the cheap China knockoffs. I think the bad coil issue was for the older stuff but people always swap coils first because it's a no brainier. On 80's OMC the power packs are a known biodegrade issue. I'm buying a 6hp today that does not run. Wish me luck.



Didn't know that. Right now I'm deciding if I should buy a used one off of Ebay for about $30 or buy a new OEM or CDI Electronics one for $60. I will be selling this motor so right now I am leaning towards the used one.


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## Stumpalump (Jun 2, 2017)

I have a "good" used one as well. Good enough to get it started. Spend the 60 bucks. That thing will fire up by just looking at the pull starter with a new one. That will help you get top dollar for it later and no hassles with a potentially bad part now.


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