10r77a rich lean adjust

[dmo1989]

Hey I recently got a 1977 9.9 johnson carb was gummed up so I took it apart and cleaned I didn't take not of the turns the rich and lean knob was at. Does anyone know how many turns from seated it should be ?

 

[flyingscott]

1.5 turns out should get you started then you can find tune it after it is warm

 

[dmo1989]

First outboard after I get it warm do I go leaner until it coughs and then turn it richer 1/4 turn or do I go richer? Or do I just play around until it's highest rpm

 

[flyingscott]

Turn until you get a lean sneeze then back out 1/4 turn and fine tune from there.

 

[909]

As mentioned "lightly" seat the screw. Then back off 1.5 turns. Then lean the adjustment until it sneezes or dies. Then back out 1/4 turn and don't touch it. Pull the screw knob out and set it dead center. After doing this test in a bucket, repeat it on a boat in a body of water under load.

Run it on a boat (wide open throttle) for a decent period of time to test , the suddenly kill the throttle to idle. It should not die. If it does back out another 1/4 turn richer and repeat the test. After you are confident you have it adjusted correctly pull the screw knob, set it dead center, and don't ever touch it again . Forever.

 

[dmo1989]

OK I got idle set nicely but now under throttle it will miss randomly every few seconds. New plugs good spark on both plugs, compression is around 120 both cylinders, took carb apart and cleaned again. It will run great for 10-15 seconds then a hard miss and run great again over and over

 

[jimmbo]

Sounds like a Lean Sneeze, richen it up 1/8 turn and try again
Did you verify the Sync between the Carb and the Spark Advance, when you put the carb back on?

 

[dmo1989]

How would I do the sync?

 

[dmo1989]

So update found what's causing the random miss. One of the coil packs has a small crack and was intermittently losing spark to ground

 

[oldboat1]

I have a couple of early '80s 9.9s, and find that cold starting sometimes requires a slightly richer setting, then back off to the leaner setting for running. #5 is a good instruction (if maybe a little stringent on the "set it and forget it" approach.)

 

[dmo1989]

Got it all figured out runs great now but now oil coming from prop so need to change propshaft seals hard to find parts for this oldie haha

 

[racerone]

Why would it be hard to find the parts??----The lower unit from a 74 model will fit on a 2005 model.----Slight difference internally but it fits.

 

[kbait]

Check gear lube before resealing.. likely unburned sludge oozing down from exhaust housing. Especially since it was running rough until you got it dialed-in.

 

[dmo1989]

Gear lube was about 1/4 water when I checked flushed it out with gear oil until seals come to try and prevent corrosion.

Why would it be hard to find the parts??----The lower unit from a 74 model will fit on a 2005 model.----Slight difference internally but it fifits

Everywhere I look for parts say unavailable for my year would newer seals and such work on a older model?

 

[racerone]

Going to be blunt here, as usual.-----You are looking in the wrong place talking to the wrong people.------Order a seal kit for a 1992 model 9.9 / 15 HP.----Parts such as the gearcase seals are the same year after year !!!----If in Canada order a seal kit at ---evinrudeparts.ca----Stuff is available all day long !

 

[Crosbyman]

whatyou need ....did you ask the folks at IBOATS on this site ??

 

[Crosbyman]

 

[dmo1989]

#2 on that diagram the propeller shaft seals I found some now though