55hp , 1977, idling and timing questions

[scott_maier]

I was hooking up the control cables for this motor and had the brilliant idea to disconnect that "spark control lever" on the starboard side of the motor. :facepalm: This is the large lever that the throttle cable connects to on the bottom and on the top it connects to the timing plate with a smaller link. The lever consists of two pieces with a large spring between them. Anyway, it seemed like it was binding so I took it off, disassembled it to clean the old crusty grease reassembled it and put it back on. The cleaning didn't make much difference, but I think I screwed up the timing in the process and now the motor won't idle. I also changed the length of that arm that connects the lever to the large throttle cam up at the carburetors. I have a johnson shop manual and went thru the link and sync to no avail. It'll start, run for a few seconds then die, I think it's flooding out.

It was idling fine before I did this by the way, I was just hooking up the control cables before i screwed it all up. All should be well with the carbs, spark and fuel pump, i rechecked compression on both cyl's and it's 150 on both. The only other difference is I'm testing in a barrel of water instead of the muffs.

I think I need to start from scratch as far as the link and sync goes, but I'm not sure where to initially set that adjustable link that connects the spark control lever and the throttle cam. This is part #73 in the following diagram.

http://www.crowleymarine.com/johnson-evinrude/parts/43353.cfm


Any suggestions? Boots to the head are also welcome...

 

[OLDIRON]

Re: 55hp , 1977, idling and timing questions

Hi. Don't know if this will help, but on mine, with the control in neutral, the lenght from the center to center of the linkage is 6 3/8". Leaving 3/4" of threads exposed on the plastic clevis end.

 

[scott_maier]

Re: 55hp , 1977, idling and timing questions

Hi. Don't know if this will help, but on mine, with the control in neutral, the lenght from the center to center of the linkage is 6 3/8". Leaving 3/4" of threads exposed on the plastic clevis end.

Ok. thanks alot. Hopefully that'll get me in the ball park.

 

[scott_maier]

Re: 55hp , 1977, idling and timing questions

As bad luck would have it the top carburetor inlet needle was stuck closed and not letting any gas in! That little wire spring connected between the needle and float arm was stretched a bit and not pulling the needle out of it's seat. So I squeezed the the spring closed by hand and got it working. The thing I don't get is that the fuel comes from the fuel pump into the top carb first, but even tho the top carb wasn't letting any gas in the bottom carb bowl was filling up. Must be a bypass or something in there. (Of course the carb issue would happen right after I messed with the timing linkage making me think the timing was worse than it actually was!) Anyway, got both carb bowls full and eventually got the motor to idle. To get the timing back I disconnected the link(part #73) connecting the timing advance arm and the throttle cam then set the timing without the link. Then I shut off the motor and adjusted the length of the link. I had to repeat that step a few times, but it seems good to go now.

Looks like i'll have to rebuild the carbs in the near future...

 

[scott_maier]

Re: 55hp , 1977, idling and timing questions

Today after work I reset the timing according to Joe Reeves method posted in the FAQ . My wife helped me, she was the official key turner while I'll held the timing light on the flywheel.

Now it's running like it was before, okay but not perfect. The engine misses a bit at idle, .. Hopefully a good cleaning of the carbs and rebuild kits will take care of that.

 

[scott_maier]

Re: 55hp , 1977, idling and timing questions

The low speed jet was missing in the top carburetor, so putting a new one in there plus new carb kits should smooth things out...I hope.

 

[scott_maier]

Re: 55hp , 1977, idling and timing questions

Had just enough time last night to put the low speed orifice in that upper carb. It smoothed it right out, but I still have to tweak it a bit, just need a few more hours of play time

 

[scott_maier]

Re: 55hp , 1977, idling and timing questions

Talking to myself here, but what else is new. I put the carb kits in last night. I found a tiny bit of crud stuck in the lower carburetor low speed orifice and the same carb was also missing that center gasket/oring that sits in the middle of the bowl and goes around the pick up tube assembly. Now she fires right up and idles nice and smooth. She'll actually idle with the throttle plates closed like the motor is supposed to do! And I put the timing light on and got it at 3 deg. +/- .5(eye ball check) . So now I'm back to where i was 2 1/2 weeks ago