# Johnson 4hp woes



## Weldorthemagnificent (May 3, 2018)

I picked up this little motor for my 11’ boat I am working on. Seems like the perfect weight for the little boat. Anyway I bought it as a non runner and I’m pretty good with carbs so I started there. It was pretty clean already with a little grit in the low speed jet. Aha I thought. Motor started and for one brief shining moment of glory ran smoothly for 20 seconds and quit. Wouldn’t restart even spinning it with a drill. Noticed the engine was quite hot for such a short period of time (yes it was in a barrel). So an impeller is due for sure. What I’m not real experienced in is ignition. I’m pretty sure these coils aren’t quite in factory condition and will need replacing. Probably go ahead and get all new everything. 
My question to those more experienced than I is. Is this as simple as removing and replacing, or is there some trickery I should know?


Sent from my iPhone using Tapatalk


----------



## Weldorthemagnificent (May 3, 2018)

Sent from my iPhone using Tapatalk


----------



## Weldorthemagnificent (May 3, 2018)

Sent from my iPhone using Tapatalk


----------



## Weldorthemagnificent (May 3, 2018)

Also the plug wires get hung up on the fuel pump with the cover on. Seems like there’s got to be a better way. 


Sent from my iPhone using Tapatalk


----------



## Pappy (May 3, 2018)

That is exactly what you do want to see when picking up an older vintage engine! Those are original coils. Shows that the engine sat for probably decades. Am betting the throttle roller has little to no wear as well. 
Put nothing but OEM parts in it. Looks like a 4hp? If so that engine puts out almost no water out the small holes. What does come out is pushed out by exhaust pressure as the water passes by the holes. Place your hand back there and see if it gets wet with mist. That cylinder head will run a bit warmer than what you are used to. Still do a water pump and by all means make sure the pump is completely submerged in your barrel prior to starting and running.


----------



## Weldorthemagnificent (May 3, 2018)

Kid I picked it up from said he did impeller. I’ll have a look before I order one. While spinning it with the drill I put my hand by the holes and it was misting a bit. 


Sent from my iPhone using Tapatalk


----------



## Pappy (May 3, 2018)

If he did an impeller then by all means....re-do it as it prob was a Sierra part. Notorious for fitment issues. I used to laugh at the posts I would see in the AOMCI forums where guys saved a bit of money on aftermarket then posted about all the ways they were shaving down the impellers to make them fit properly.


----------



## Weldorthemagnificent (May 3, 2018)

I was looking at parts online and wondered about the quality of Sierra vs oem. I don’t do a lot of outboards. Aftermarket isn’t always bad. Fiddling with snowmobiles, I’ve had good luck with Kimpex parts. 
Thanks for the heads up. 


Sent from my iPhone using Tapatalk


----------



## Weldorthemagnificent (May 24, 2018)

So I followed Pappy’s advice and ordered oem parts. Made a couple mistakes, first I ordered from marineengine.com. Although they have great parts breakdowns, they ship ups and the customs brokerage fees were about 40% of the value (I’m in Canada). Secondly was not dropping the lower unit before ordering parts. Think I found the heat issue. There was no grommet on the water pump housing where the tube goes in. Tube was also bent to the side like it wasn’t even in the hole maybe. Anyways I’ll source a grommet locally. Once that’s done, I will turn attention to the ignition. 


Sent from my iPhone using Tapatalk


----------



## CedarRiverScooter (May 25, 2018)

Tangential story here . . .

I also have a 4hp, 1969. The starter pull would fail to engage about 1/2 the time.

I took it partially apart & found one of the plastic bushings cracked.

Went to the local dealer & they didn't want anything to do with helping me find a replacement.

I did find it online at Boats.net.

Turns out it is a very common part, I bet the dealer had it in a bin if he just looked for it.


----------



## Weldorthemagnificent (May 25, 2018)

Most dealers don’t want to fool with parts. They are holding up an 80 dollar an hour job on the shop floor to look for a part they’re going to make 3 bucks on. That’s what I love about online parts shopping. 


Sent from my iPhone using Tapatalk


----------



## onthewater102 (May 25, 2018)

Pappy said:


> If he did an impeller then by all means...re-do it ...



Love it. 

Trust no one with used motors - check the impeller (not the stream) every time. Good luck with this one OP.


----------



## Pappy (May 25, 2018)

Weldorthemagnificent said:


> Most dealers don’t want to fool with parts. They are holding up an 80 dollar an hour job on the shop floor to look for a part they’re going to make 3 bucks on. That’s what I love about online parts shopping.
> 
> 
> Sent from my iPhone using Tapatalk



Weldor, that is the exception,not the norm. 
We are at $96/hr. and will take the time to look up, sell, order as necessary, and spend a bit of counter time trying to help a customer self-diagnose. What we will not do is look up and supply part numbers over the phone to someone. If they want to order parts over the phone we will be more than happy to do that as well. 
All the dealerships I know of around my immediate area do the same thing. We have all been in business for a long long time and this is possibly one of the ways we have done this.


----------



## Weldorthemagnificent (May 25, 2018)

The impeller looked good. Looked just like the oem one I bought. I swapped it anyways but I’ll hold on to the spare, I have a 6hp I’m going to get into next. 
There is a good marina near me that will take time to help with parts. The smaller one man shops don’t want to fool with the diy guys and our obscure parts. 


Sent from my iPhone using Tapatalk


----------



## Weldorthemagnificent (May 26, 2018)

Went by the local marina today and they had my grommet so I installed the foot and changed gear oil. Then up top went new coils and ignition bits. 


Sent from my iPhone using Tapatalk


----------



## Weldorthemagnificent (May 26, 2018)

https://www.youtube.com/watch?v=lkg0JfcWq8Y

It was tough to start at first and I had to use a drill. Then all of a sudden it wanted to go so I ran it for a while. Persnickety thing to tune but I think I have it dialed in enough to try on the lake. 


Sent from my iPhone using Tapatalk


----------



## Weldorthemagnificent (May 26, 2018)

Thanks Pappy for the advice!


Sent from my iPhone using Tapatalk


----------



## Pappy (May 26, 2018)

It's running a bit on the rich side but you can dial that in on the water........nice job!


----------



## Weldorthemagnificent (May 27, 2018)

Got the idle leaned out a bit and I can slow to a crawl. Took it out on the lake and it ran fine. Started 2nd pull. Fiddled with the high mixture and found the sweet spot. It pushed the boat along nicely but was no where near plane as I have seen some of them on YouTube. This would make a great trolling motor/kicker on a larger boat or be badazz on a flatback canoe. For my 12’ aluminum, I think I’ll look for a 6. 


Sent from my iPhone using Tapatalk


----------

