1977 Johnson 115 hp ETL Idle Question

[Charlie5653]

not sure about that red stuff, only thing I can think is I rebuilt the starter also. On that lower starter bolt reinstall I put this color permatex on it?

 

[racerone]

The red stuff is a coating put on in the factory.-------Those pistons / rings look to be low hrs.-----But that is what you know now and not before this low cost inspection.----What does # 4 look like ?

 

[Charlie5653]

#2 has 122 lb #4 has 120 this side looks to me to be pretty much the same. GREAT TEST ... the covers all look pretty much the same inside as well.

Thoughts?

 

[racerone]

What did you do to go from 108 compression to 120 PSI ?

 

[Charlie5653]

#4 per request

 

[Charlie5653]

the 116 108 was from memory probably 6 weeks ago and I didnt write them down. also this morning I took all the plugs out and grounded them to test.

sry for that bad info

 

[Charlie5653]

heck, maybe these gaskets were drawing a bit of air, they are really bad shape. is that a possibility?

 

[Charlie5653]

Racer, Also what kind of sealer would you suggest for these 4 gaskets? On the carbs and intake I used grease because I figured I probably would be taking them back off again.

And, Do you live in the states?

 

[racerone]

Not in the USA.--------Use Permatex aviation sealer.----Just a thin smear will do.

 

[Charlie5653]

Ok, Should I clean that red stuff out of there or simply close it back up

 

[Charlie5653]

Ok, parts ordered. Will post back in 4 or 5 days when parts arrive/install.

Thanks so much for all the help and advice, Charlie

 

[Charlie5653]

A couple more observations after cleaning up the bypass covers. all 4 covers looked the same, mild to significant build up on the top 3/4 of all 4 covers, the lower 25% of all 4 were slick clean. This appeared to me as the majority of fuel was entering the chamber from the lower 25% of the cylinder. (wasn't sure if there is any significance to that, so I wanted to share)

Also, If I rotate the pistons all the way down (so I can see a portion of the top of them) they appear to have build-up on them?
I can try to take a pic of one if you would like? Also not sure if this is the norm so wanted to share.

Also, found a crack in one of the coils, even though it's sparking fine, I ordered a replacement.

Cheers for now, and Thanks a million !! Charlie

 

[Charlie5653]

Would the ethanol be a problem, should I be using an additive to eliminate the ethanol?

 

[Charlie5653]

Update: Gaskets installed --- This time I did things a bit different, and started the motor in a test tank.
The motor will idle with maybe 1 lean-sneeze very seldom (3 mins or so), The idle is still pretty rough as the tach bounces around from 700 to 1100 ? maybe this is as good as it will get for an older motor?

I installed a new coil on #4 and my observed - ( with inline spark lights on all 4 cylinders at idle ) The spark color changed completely to a very noticeable brighter / sharper spark color? The other 3 coils still remain lighting every time but a more faded orange color? Note: all 4 coils old coils test good per ohms..
Is it possible these old coils could be weak?

Also while in tank, noticeable oil showing up. Ordered new seals for lower half.
will update after I get the lower seals in.

Any Thoughts??

Thanks in advance, Charlie

 

[racerone]

I rebuilt a 1984 model 140 hp for a cousin some years ago.------When he picked it up he said ----" wow I can not believe how smooth it runs now "----So if your motor is surging from 700 to 1100 RPM there is sometin wrong !!!

 

[interalian]

This is how mine ran on its first start after rebuild. In a barrel with enough water.

https://www.youtube.com/watch?v=aDwttmHO1Gg


And this is on muffs after running all summer.

https://www.youtube.com/watch?v=G2WBqUFurko

 

[Charlie5653]

Interalian, I'll try to do a video of my idle tomorrow. Your engine sounds great to me. Well Done!!

This motor set for 12 yrs, I cant believe it even started. This model has to be a workhorse !!

Still seems lean to me with spits of wanting to idle well. maybe top and bottom seal are sucking a bit of air? I'm unclear on if the seal is bad will it suck air? or does the big Oring on the crank have to be bad in order to draw unwanted air.

I also can tell you folks this : with the engine at idle I can cover up 3 of the inlets on the breather/silencer and it doesnt affect it? if i cover the last one it dies....

 

[Charlie5653]

With all the help I received here I felt obligated to return and share my final results. What a challenge this was. let me make a long story short and explain what actually fixed the engine and the final key ingredient to perfect the motor of old... after countless hrs rebuilding carbs (3 times), coils, powerpak, air leaks ect ect ect... the engine continued to cough and die and idle was horrible.. One day last yr I went out again to piddle with it, filled up the water barrel and fired it up...... all of a sudden the idle picked up to around 2k and stuck?? I turned it off and it would not start back up... All I could think of was the shear pin had sheared and blew it completely out of time. removed the flywheel and yes, it had sheared off completely. I installed a new key and the engine purrs like a kitten. I think it runs better than when it was new.. lol So, in closing another thing to check is the shear pin under the flywheel.. Apparently on this engine, if the shear pin is partially bent but not sheared it can throw the engine just enough out of time to make you pull your hair out.. Cheers, off to catch some largemouth... Thanks for the help here again!!