1977 Johnson 85 horse runs good on 3 not 4

[MRneatfreak]

Been troubleshooting this motor/boat for some time now. I installed 3 new coil packs even though they probably didn't need it, and I have swapped power packs although I'm not sure they go with this motor. The numbers on them don't make any sense. Anyway it starts fine, and then after warming up a bit it acts like cyl #3 is out of timing and sometimes will stop the engine or if it doesn't there will be a puff of smoke out the exhuast. But if I disconnect cylinder #3 and run it, it seems fine. The carbs are off a different motor, but are practically new inside. I have replaced all the fuel lines, new primer bulb, fresh fuel, etc. I set the idle timing by cranking the engine with no spark and set it at 4 degrees btdc. I had some trouble with that, the screw was all the way in so that might be part of the reason. I don't know.. Also when I advance the shift lever all the way forward the timing base doesn't move all the way forward? Lost in the sauce on this linkage stuff. I have the service manual for this year and horse of engine, but...

Ugh, is there a Mega byte limit on videos? It won't upload 30 seconds of recording.

 

[nwcove]

Re: 1977 Johnson 85 horse runs good on 3 not 4

post the vid on you tube, then post the link.

 

[emdsapmgr]

Re: 1977 Johnson 85 horse runs good on 3 not 4

It is possible that you have one of the coils connected incorrectly to the power pack. That could have two cyls firing at the wrong time. The engine may run that way, but backfiring is likely and the engine will have no power. Double check the coil wiring to the power pack terminals with the factory wiring diagram. The degrees of idle timing is only important to get the engine to run the first time. The timing gets reset when you set the idle when the boat is floating in the water. The idle rpm should be set between 650 and 750, set when the boat is floating in the water and is in forward gear. The timer base should move freely/easily with the spark advance lever. It is possible the timer base will stick on older engines-when the grease dries out-it may not move freely.

 

[MRneatfreak]

Re: 1977 Johnson 85 horse runs good on 3 not 4

Ok sorry it took so long. I posted two vids the first one says firing on all 4 cylinders and shows the issue at hand at about 19 seconds.
http://youtu.be/EJIx9bvv908

and the second vid, with the #3 cylinder disconnected and a smooth idle.
http://youtu.be/VZqE2tpQB2Y

 

[MRneatfreak]

Re: 1977 Johnson 85 horse runs good on 3 not 4

It is possible that you have one of the coils connected incorrectly to the power pack. That could have two cyls firing at the wrong time. The engine may run that way, but backfiring is likely and the engine will have no power. Double check the coil wiring to the power pack terminals with the factory wiring diagram. The degrees of idle timing is only important to get the engine to run the first time. The timing gets reset when you set the idle when the boat is floating in the water. The idle rpm should be set between 650 and 750, set when the boat is floating in the water and is in forward gear. The timer base should move freely/easily with the spark advance lever. It is possible the timer base will stick on older engines-when the grease dries out-it may not move freely.

I have double and triple checked myself on this one, the sticker is still intact on the power pack lid that shows where everything goes. I also have the Johnson 1977 service manual and it shows where everything is connected too. Just to make sure I tried reversing #1 and #3's plug leads and that made things worse. I think I am going to shell out the money for a known good power pack.

I also have another question. The shifter linkage won't extend far enough through the movement from the remote box to get in reverse, but forward is ok. I thought the adjusting trunnion nut was out of adjustment at the carb holddown nut, but I had my son move the lever up front, and it won't push far enough aft on the engine, the remote box lever is almost parallel with the deck. It seems I can engage reverse on the engine by moving the linkage by hand. Also noticed the cable guide is moving on/around the cable? Isn't it supposed to be locked in place around the cable?

 

[MRneatfreak]

Re: 1977 Johnson 85 horse runs good on 3 not 4

Well I bought a new CDI powerpack specifically for this engine from a marine supply distributor. It definetly sounds different, but I'm not sure if for the better. I went to stick it in gear and opened another can of worms, found out I could only go into fwd but the shift lever would not go aft. Took the remote box apart and it all looked ok. Put it back together and this time would only go in reverse but not forward. This is just the shift box, as it is not engaging drive gears on the motor, which I verified by being able to spin the prop with the engine off.

Gonna have a friend show me how to properly rig the cables. It looks pretty involved according to the book. I'll post another vid later on with the new power pack.

 

[nwcove]

Re: 1977 Johnson 85 horse runs good on 3 not 4

not sure if its a myth or fact, but with your cdi ignition you shouldnt even roll the engine over without having your spark plug leads grounded. ( watched the vid and saw the lead pulled and allowed to hang)

 

[MRneatfreak]

Re: 1977 Johnson 85 horse runs good on 3 not 4

Shifter not going into reverse, but can move linkage by hand to get into reverse, don't know what to adjust? I removed the ancient evinrude control box because something was binding inside, but never could see what when I dissassembled.
http://www.youtube.com/watch?v=2Rb6XEAI3g4&feature=channel

Cold start and the miss I am experiencing even with a new powerpack.
http://www.youtube.com/watch?v=VBD3np3yvLQ&feature=channel

More; seems to well on the muffs when rev'd up a little, starting to think carbs?
http://www.youtube.com/watch?v=minbaL8V8s4&feature=channel

 

[MRneatfreak]

Re: 1977 Johnson 85 horse runs good on 3 not 4

not sure if its a myth or fact, but with your cdi ignition you shouldnt even roll the engine over without having your spark plug leads grounded. ( watched the vid and saw the lead pulled and allowed to hang)

You're right, I have read that before :facepalm:. I'll make sure not to do that with my Brand New Power Pack .

 

[MRneatfreak]

Re: 1977 Johnson 85 horse runs good on 3 not 4

Well I think I ruled out the ignition. I ran it in the water and the miss went away when I throttled up in gear. It does well pushing the boat. I took it out for about 3 hours today in the bay. I can't go ahead full, other wise it will die, but if I go half power, and then throttle up all the way it'll run full bore for about 4 seconds and die if I don't throttle back. But if I throttle back and I can keep it from dieing. So not sure if its a fuel pump issue or a carb problem? When I running around at half power, the primer bulb is kind of soft, but at full power it is hard, mind you it'll run all day at half power. I wanted to check the water seperator but had nowhere to dump it. Maybe it's full of water and when I call for full power some water gets through and chokes the engine? I'll have to check it.

 

[emdsapmgr]

Re: 1977 Johnson 85 horse runs good on 3 not 4

Check for a weak fuel pump. When running at high rpm's try constantly priming the fuel hose bulb. This will force extra fuel into the carb bowls. If it runs fine at WOT as long as you constantly prime the bulb, you may have a weak fuel pump.

 

[MRneatfreak]

Re: 1977 Johnson 85 horse runs good on 3 not 4

I think I tried that but I don't remember the outcome for full throttle, all I remember was the bulb was hard at full throttle? I had my son drive and I sat by the engine and kept squeezing at half power = no change. If the bulb was hard (full) this is good right?

I read some other threads about a person rejetting a carb to run the higher altitudes in the rockies. And it dawned on me that I took the carbs from my other engine which I knew were good (low compression on #3). That engine I think is either a 115 or 135, have to check the model under the coil packs to be sure. Anyway that larger engine would require more fuel, so maybe I need to play the jet change game :facepalm:.

During week 1 when I got this setup I couldn't get anything but a backfire, so dissassembled the carbs that came with it, looked freshly rebuilt, watched a youtube video (the downfall) which instantly turned me into a professional , and I removed the welch plug on a high speed jet. The kit I already opened had a welch plug that was slightly too small in diameter and was too loose. The marina I got my parts from http://harborviewmarine.com/ couldn't find any reference of the carb I had and a kit that was available for it. In fact of the three Johnson's I have they didn't have any reference as far as part numbers matching for carb kits? So I took from peter to pay paul and transfered carbs that I knew worked not too long ago. In fact they still were wet with fuel.

I'll take the choke plate off and get some numbers, maybe you guys can steer me to a link to a carb kit.

Getting shoulder surgery tomorrow, I wonder how much I can still do (physically) next week .

 

[MRneatfreak]

Re: 1977 Johnson 85 horse runs good on 3 not 4

I checked the fuel water seperator and only had about 2 ounces of water when I dumped it in a jug, with about 12 ounces of fuel. So that theory is done.

I found the choke setting in automatic. There is choke, auto, and off. So wondering if maybe at full throttle, the vacuum sucks the choke shut with it in auto? Might be something to experiment with.

I took all four carb drain screws out and pumped the bulb, didn't see anything come out except fuel. Then I took the high speed adjust screws out on the sides of the carb (I think thats what they are). And blew compressed air through them with the bowl drain screw removed, both directions. Then I got curious on the jets, so I took one out and it said #30 on the side and looked shiny new. So then I took a jet out of the carbs that were originally on the motor and they are #25 and were a dull color. My plan is to install all four #25's in the carbs and repeat the test in the water. What kind of gasket should be on the high speed adjust screws? Black rubber or that red gasket? One set of carbs has a black rubber one, and the set that's on the motor are the red paper ones. The red paper ones I'm afraid are going to vibrate loose when I go to, turn them out for adjustment?

 

[MRneatfreak]

Re: 1977 Johnson 85 horse runs good on 3 not 4

My service manual lists what the slow and fast speed hole sizes are, and my manual covers 85 and 115hp:redface:.
xxxxxxxxxx 85: 115:
High speed .049 .059

Low speed .025 .029

So I already did 2 low speed orifices, got a little work ahead of me. Always fun trying to catch the orifices before they fall down the side of the motor into no man's land .

Are the high speed screw's adjustable? I would think not as fuel would leak out?

 

[BonairII]

Re: 1977 Johnson 85 horse runs good on 3 not 4

Have you tried to bump the choke and/or pump the ball at WOT to see if the motor picks up? Do you have the correct plugs/gap?

 

[MRneatfreak]

Re: 1977 Johnson 85 horse runs good on 3 not 4

Didnt bump the choke at WOT, but I think I did try to squeeze the ball and It was hard. I already know the jets are the wrong number I just pulled the high speed jet and it was a #61C, the service manual calls for a #49. So I already opened that can of worms, got 2 1/2 of the correct 8 jets installed. 75% sure the plugs are correct, the Johnson dealer sold them to me. Have to check the numbers though. The service manual calls for the gap to be .040, but I think they were at .030. I set them at .040, it didn't change my rough idle anyway.

 

[MRneatfreak]

Re: 1977 Johnson 85 horse runs good on 3 not 4

L77JC4 is what's on there now. The book calls for Champion L77J4 or AC-M40FFX.

So let me guess I need to regap to .030?

 

[BonairII]

Re: 1977 Johnson 85 horse runs good on 3 not 4

Didnt bump the choke at WOT, but I think I did try to squeeze the ball and It was hard.

Bumping the choke would've given you a quick shot of richer mix that would have either perked up the motor...or bogged it down(if it was already getting enough fuel).

 

[MRneatfreak]

Re: 1977 Johnson 85 horse runs good on 3 not 4

Well I changed all 4 low speed and all 4 high speed jets between my carbs, now the engine has 25's for low and 49C's for high. Started it and still has the pop/miss but it isn't consistent. Gonna take it to the lagoon right now and see what it does with water backpressure.

I don't remember the rule with WOT and operating at night, other than to have bow and stern nav lights lit. I think I remember WOT was ok as long as you didn't see any other vessels with their lights on in close proximity. Is that correct?

Can't wait till daylight, cause it'll be a week or more before I get in the water again. It's one of those things where you made a significant adjustment and you want to know what the outcome is.

I guess I could leave it on the trailer, all hooked up and go WOT, just like all them people that are too lazy to pull their boats onto their trailers when loading.

 

[MRneatfreak]

Re: 1977 Johnson 85 horse runs good on 3 not 4

Bumping the choke would've given you a quick shot of richer mix that would have either perked up the motor...or bogged it down(if it was already getting enough fuel).

I think I did that with half power, but it really didn't do anything other than start to kill the motor. Which I was already fighting problems with at full power, so didn't try it at full.