'59 - 33hp Evinrude cylinder pop

I am working on a full restore on this engine. I have replaced all magneto parts, plugs, wires, carb kit, cut-out switches, leaf plate, and all wiring. As far as I can tell I've replaced anything that could fail other than pistons. It will start up but I am getting a distinct pop on the bottom cylinder. When I pull the bottom plug wire its running smooth but when I pull the top it sputters, pops and stalls.
My instinct is that its probably timing but I wonder if there is anything I havent thought of. I know i dont have the carb completely dialed in but I cant imagine why that would affect only one cylinder. Possibly carbon build up?

Thanks in advance.

Decarb it with seafoam deepcreep. There's a thread on this issue.

Sent from the dust in front of you!

Decarb definitely helped. Still running a little rough, maybe sync the carbs and I'll be in good shape.

thanks

Glad to hear it helped. Don't be afraid to give it another shot. Synching the carbs might just be the last you have to do. Good luck man.

Sent from the dust in front of you!

First off where is the pop coming from? Carb? or does it sound deeper? Crankcase halves leaking at the sealing line?
if it is popping back through the carb then reed seal at idle may have an effect. If it sounds deeper you may have a bottom crank seal leaking. If you simply richen the mixture does it go away? If you want to check crankcase seal you can take soapy water and spray along the crankcase seal area and see if it is leaking. Carb or electrical cleaner will do the same. You can check the intake by-pass covers the same way and the exhaust as well although I doubt the exhaust has much to do with it.
BTW - Evinrude did not manufacture a 33hp in 1959 so you apparently have a later model engine than you think if that is the correct horsepower. The 33hp for EV started around 1965 or so.
Evinrude did manufacture a 35hp in 1959.

You are correct, the motor is a 1965. I am working on a '59 boat with a '65 engine (33hp) and I just mixed them up in my heading. Thank you for pointing that out though.
I de-carbed yesterday and it got better, today I synced the roller and put the needles back to factory settings and it got better still.
I'm restoring the motor one google search at a time and each time I change something I start it up to make sure it still works so I dont end up chasing my tail. The challenge that I've come to realize is that it will never work right until it all works together.
I feel like I'm at the point now where I need to tighten everything up and get it on the water under load, I may not be exactly at fine tuning but I'm close.
I dont post a lot but believe me I've read hundreds, you guys are great, thanks.

Your welcome! I really hope you get everything ironed out.

Sent from the dust in front of you!

edit: 65 33hp evinrude.

I know this a LONG shot. I know you can only tell so much from a you-tube video but I'm putting it out there anyway. I struggled a lot with the timing. Manuals are great until they tell you to use ### tool, then no so much - I did finally find another way. I used to work on my old Norton back in the 80's so I'm not lost but this is my first outboard and I have no frame of reference. I'm still getting a "bump?" and I really think its timing. After carb adjusting, the firing is much more consistent between the two when pulling the plugs. Maybe it is what it is, maybe it needs to be under load, maybe it needs the cowling installed to calibrate air flow (being painted). Maybe..its just right.
This is the video, I didnt see anywhere that attaching a link was prohibited, if it is I apologize.

https://www.youtube.com/watch?v=HKaOExqdles&feature=youtu.be

Okay....at this point I want you to put the engine in the lake or wherever you run it.
The static water line will build back pressure. Am thinking you will like the running quality at that point.
You will need to tweak the mixture adjustment for idle quality in the lake with the change in back pressure.
Bring the needle in in small increments and let the engine steady out for around 20-30 seconds each time. When the idle RPM starts coming up and smoothing out keep going until you get a lean pop or the engine slows down. When either one of those happens richen the mixture again around 1/4 turn or a little more.
These particular engines will have a tendency to pop when coming off plane to idle quickly. This is normal but you can run a richer mixture to minimize it.
It is a 50 year old 2-cylinder 2-stroke so the running quality will not be like today's computer controlled injected engines.
Let me ask you this. What kit did you buy for the carburetor? Did it have the needle packings with the kit?
Would definitely run extra oil in the engine as well.

You're the best Pappy, thanks.

I bought almost everything off ebay and for the most part had no problems. I think I know where you're going, the carb kit I bought was whatever fit but I've read several threads about having the packing correct and I'm nervous about that. The packing that came out (high end not idle) had two of the firm washers and then the rest of the packing but the manual only showed one - I installed one.
I think you're right about putting a load on it. It's an effort to put it out on the water but maybe its worth it.

In an OEM kit you get several cork packings plus nylon. The nylon are placed on either end for bearing loads and the cork are placed in the middle.
At any rate you definitely want to use more than one packing. Use three apiece if the kit provided them. You will need to re-tighten the packing nuts two or more times before they stay in adjustment.