Johnson 60hp 1982 idle adjustment screw?

[Bosunsmate]

Hi.
Ive bought a Johnson model J60TLCNM, the last owner said it was running rough and stalling out.
Ive cleaned the carbs and ive put it back together. Cold Compression (100psi/95psi) and spark seem good although i didnt check timing.
Theres a screw on the top front middle of the carbs which on my merc were a idle adjustment screw/ air mixture.
Is the screw on this an adjustment device?
The top and bottom carb screw were both screwed in tight which would in other motors i have worked on resulted in a lean sneeze. Id like to know if possible what a good starting setting is if these screws are meant to be backed out. They have little gaskets on them which im not sure indicates whether they are meant to be in tight or not. I definitely dont want to run lean
Thanks

 

[F_R]

Re: Johnson 60hp 1982 idle adjustment screw?

They are to plug the hole, not to be adjusted. As you suspect, that is the reason for the gaskets. The mixture is by fixed jets. Perhaps somebody has damaged them by poking wires or drills through them? Or worse yet, drilled them oversize?

EDIT: The idle jets are deep in the hole, after you remove the screw/plug.

 

[emdsapmgr]

Re: Johnson 60hp 1982 idle adjustment screw?

You can check out the original factory exploded parts diagram for your carbs on this website: epc.brp.com The carb diagram for your year engine shows the fixed idle and intermediate jets which hide behind the screws in question. You may want to remove these jets and visually check to be sure they are not restricted, perhaps by dried fuel gel.

 

[Bosunsmate]

Re: Johnson 60hp 1982 idle adjustment screw?

Thanks for both of those posts. Im very glad i didnt run it with them backed out as that was the safety setting i thought id start on, which is what i would done on my merc.
Il look into it more tomorrow when the suns up and il see if those jets look corrupted if it isnt running right then.
It was dribbling two stroke mix out of the top carb when it wouldnt start so i have readjusted the float and checked that the inlet reeds are ok so hopefully thats covered off the fuel dribble. I did get it started once i got the choke hooked up but i cut it straight away as it was very powerful/fast with no backpressure on.
Its nice to have a trim and tilt engine to look forward too.
Cheers

 

[Bosunsmate]

Re: Johnson 60hp 1982 idle adjustment screw?

I restarted it and it went ok for about twenty seconds but it then had some tiny backfires so i cut it. I restarted it and it kept having these small backfires and then it started varying in speed.
It picked speed up quite a lot and i thought thats too fast so i went to cut it and it wouldnt. First time ive experienced that. It was running longer on muffs and at speed more than any i have ever done on muffs before, i started to think it may self destruct, it was in control of itself not me, however it was running really well, ie no backfire.
I couldnt cut it and i wanted to get out of there but i also wanted to save the motor so i made the decision to go in and pull the fuel disconnect as that was the quickest thing i could come up with. I then ran and waited around the other side of the house for the piston to go through the door or it ran out of fuel. It eventually stopped after about 30secs.

I was wondering how a motor can run with the engine turned off- i suppose its heat from the cylinders that ignites the fuel to replace the killed spark?
I took off the rear cover to look at the thermostat and it opens fine.
This red thing i assume is the poppet valve looks melted like its being under a flame almost. The long end which goes into the engine is the melted part.
It moves ok in the rubber housing but id say the melted plastic would restrict the flow of water along it somewhat but not massively.
Any thoughts on it?
Im removing carbs to check the jets

 

[Bosunsmate]

Re: Johnson 60hp 1982 idle adjustment screw?

Update- i cleaned up the poppet+ carb jets and reinstalled. She still had a small misfire and seemed to run at too high rpm, i was thinking lean condition still so i took the inlet reeds right off for a thorough inspection and they were ok. I turned the hose on and i noticed that the top part of the crankcase was filling with water. The bottom was ok.

I rechecked compression and it was still the same as yesterday.
Im picking i need to take off the exhaust cover to have a look around. Anyone done this? it looks as though i need to remove the powerhead to do this as the bottom rear screw cant be backed out far enough. I suppose i should change the lower crankcase seal while there as it looks as though i can pull it out without needing to disassemble the crankcase.
The undoing of the cover to get to the powerhead bolts seems like there are some really badly postioned bolts especially the one just behind the starter
Picture is of top crankcase inlet filling with water

 

[Bosunsmate]

Re: Johnson 60hp 1982 misfiring

Re: Johnson 60hp 1982 misfiring

It shoots water out the telltale fine. When i turn it off and then turn the flywheel it shoots further water out the telltale.
Im picking it must be pressurising the exhaust chamber as the outlet for the telltale is at the bottom of the exhaust cover (I did this with LU removed and hose on inlet pipe)

 

[Bosunsmate]

Re: Johnson 60hp 1982 idle adjustment screw?

I had big problems removing the powerhead bolts, but i managed to get them all out, or completely dehead them. I also got the nut off at the rear. I cant seem to get the powerhead to lift off though. This is what im trying at present. As you can see it even lifts the boat completely off the ground. Any ideas?
Thanks

 

[Bosunsmate]

Re: Johnson 60hp 1982 idle adjustment screw?

I just noticed one little bolt that might of being holding it together, its directly below the fuel pump. I will undo it and look for more suspects and try removing it again after work tomorrow.
For future reference for anyone who has a similar problem. I removed the exhaust cover, the bolts came out really easily. It was fine in there as far as i could see so i just dont know how the water was getting into the top crankcase, maybe it was because i had removed the reeds, i dont know.
The cylinders were normal too. Here is the head gasket it didnt seem broken, the top cylinder is on the left

 

[Bosunsmate]

Re: Johnson 60hp 1982 idle adjustment screw?

I drilled out the head bolts which were hanging it up. Ive managed to get it separated below this lower base and the exhaust housing.
Any ideas why its still holding up?

 

[Bosunsmate]

Re: Johnson 60hp 1982 idle adjustment screw?

looks like it has the steering arm in it holding it up.
I think my only option is to bash this middle plate to bits, but this adaptor plate is nla...............
Im going to drill through this plate and smash it to bits while trying to preserve the crankcase parts above.
There will be one of these plates somewhere ready and waiting for a new rebuild to join up with!

 

[Bosunsmate]

Re: Johnson 60hp 1982 idle adjustment screw?

Well, ive gotten the powerhead off. Everything needs a overhaul but the lower seal looked ok, the o-ring wasnt but that may of happened in removal.
I need to get the exhaust housing off. How do i do this as the bolts are all seized so i want to pick the ones to do once only.
Do i remove the top two in the upper rubber mount or can i just remove the bottom rubber mount and pull it down, Ive removed the three bolts that hold the rubbermount to the exhaust/adaptor plate

 

[Bosunsmate]

Re: Johnson 60hp 1982 idle adjustment screw?

Update +conclusion.
I ended up keeping the exhaust base on, i couldnt work out how to remove it, the bolts adorning the midsection were all seized so i just ended up rebuilding the damaged exhaust base with high temp epoxy putty, from my own self inflicted damage from using a cold chisel on the seized bolts and surrounds. Luckily the base plate face was fine, especially in the crucial port side areas which contain the water inlet and exhaust outletsfrom the powerhead, itd be real bad times if there were cross channels between them if the gasket there couldnt seat properly.

I have put the motor back together after splitting the crankcase and having a quick check inside and resealing it. I went out for a brief test ride on the weekend and it went fine. I cant provide a smoking gun for why it was idling high and had a miss. It was idling so high that the mechanic i bought it off had removed the idle stop to try and get it to slow, something was wrong with it so no chance that that that was going to slow it.

The areas which may of caused the problem or contributed to it were in my personal order of likelihood of being more important-
The top of the stator had some of its green insulation disintegrated so i re-epoxied it. It might have being shorting out there.
The flywheel woodruff key was sheared so timing may of being out. I regret not trying to check timing more at the beginning but she was running so fast that it was wasnt nice to be too close to the action.
I replaced the headgasket as it was compromised causing leaking into top cylinder, either before or after the thermal run away. Compression is now 100psi on both cylinders with no water intrusion. The head didnt seem warped.
The crankcase looked like it may of had a small area in the mating face where it could of leaked.

The past owner had put in the wrong impellor and key. It seemed ok before i took it out, but it slipped at high speed, luckily i was doing a engine test on it so i realised quickly there was no telltale flow. The audible overheat alarm needs a lot more volume.

It had a impellor with a half crescent key which is not quite big enough for this motors driveshaft key area which requires the pin type key and impellor. I also am doing the LU seals tomorrow, apart from the prop shaft ones, hopefully the others stop the milky gearbox oil reappearing that was present.

In summary to anyone else who has this problem i found it a very easy motor to work on apart from the powerhead to base bolts, it seems to be very similar in design to a lot of the JohnsonEvinrude motors from the eighties across a wide power range from 40hp up.

If your engine is running fast and or missing i suggest checking the faults i listed which dont require removing the powerhead first but if you do need to remove the powerhead and the bolts arent being nice be extra cautious on the port side of the engine as that is where the most crucial inlet and outlet ports for the powerhead to the lower leg are.
So having the base plate and housing on that side in top condition is a lot more important than the starboard side which is not close to crucial ports.
Enjoy your spring all those in the Northern Hemisphere