85 Johnson 2 horse - carburetor access

[boobie]

Re: 85 Johnson 2 horse - carburetor access

Edit.......

 

[twocyclemania]

Re: 85 Johnson 2 horse - carburetor access

Sandor27: Sounds a lot like my motor. Like you I can't believe the thing won't at least give a hint of life. Currently I'm soaking the piston/cylinder with the CRC knocker loose product. In the meantime I'm going to take the carb off again and give it a going over. I'll be back soon with the results. thanks for the help

 

[twocyclemania]

Re: 85 Johnson 2 horse - carburetor access

Went through the carburetor again. Removed the high speed pickup and all passageways were clean. No cork, no gunk, no obstructions. I replaced the packings (2 each) of each of the needles and reassembled. Removed and cleaned the bolt connections for the mag plate ground strap. Soaked the piston for a couple of days with the CRC Knock-er-out solution. Nothing! The compression is still 30 lbs and the plug is dry as a bone. Can the lack of compression result in a lack of suction for fuel? I tried adding fuel/starting fluid through the carb and through the spark hole and I still can't get the slightest of ignition (yes I have spark). I'm thinking compression. Does this sound like a tare down for new rings or should I continue to soak them or any suggestions at all as to the problem and solution. Next step is to remove the exhaust plate to view the piston/rings. Out of all my motors this smallest one is giving me the most trouble. Thanks to everyone for the help so far!

 

[Bosunsmate]

Re: 85 Johnson 2 horse - carburetor access

Yes it can.
put your hand over the carb and crank it. see if you have any vacuum

 

[twocyclemania]

Re: 85 Johnson 2 horse - carburetor access

This thing is just not going to fire up. I re-checked the compression and I'm still getting 30 lbs. I'm beginning to believe the whole problem with this motor is compression. I pulled the side exhaust cover today and from what I can see there's no scoring of the piston. Correct me if I'm wrong but shouldn't the rings flex a little (in and out). I pushed on them with a small screwdriver and there appears to be no movement in the slightest. Though they're not rusted could this be my problem. Also, at this point is it worthwhile to try to soak them. I put quantities of CRC knock-er-loose into the spark plug hole for a couple days prior to this. Any suggestions?

 

[Will Bark]

Re: 85 Johnson 2 horse - carburetor access

Since you have nothing to lose I think I would mix up a solution of 50/50 acetone and auto transmission fluid and pour it down the spark plug holes and let it sit for awhile; maybe the acetone can cut thru if is gummed up. Good luck. Others may think this is a bad idea and will chime in.

 

[twocyclemania]

Re: 85 Johnson 2 horse - carburetor access

This motor has little use. The top of the piston and the exhaust chamber have almost zero carbon. There's nothing gummed up. I'm beginning to believe that the rings are stuck; maybe from sitting for years or possibly the motor got dunked and not serviced afterward. Though there's no evidence of internal corrosion I still think the rings are stuck in one position and thus I'm not getting compression. I'll give your concoction a try. As you said I have nothing to lose.

 

[Crosbyman]

Re: 85 Johnson 2 horse - carburetor access

Only one...easy option for now... soaking
keep both piston above the exhasut ports and soak. maybe she will loosen up on the rings and you will regain some compression.

check to see if soaking oil leaks out or puddles on the pistons faces. if the oil leaks out you know the rings are taking a bath

later on try to move the rings via the exhaust port maybe you can get them to move a bit inscreasing the soaking effect

keep at it

 

[twocyclemania]

Re: 85 Johnson 2 horse - carburetor access

The solution I'm using does leak out when I spray it through the spark plug hole (it doesn't puddle for very long). I'm hoping the rings will get enough of a bath to loosen up. I do believe they're not 'flexing' as they should as the piston moves. The may be stuck due to electrolysis/corrosion. Once again, this motor has little use; probably too little. I've seen a good number of pistons and exhaust areas over the years but never one as clean as this one. This motor is an enigma if I ever saw one.

 

[poida]

Re: 85 Johnson 2 horse - carburetor access

Spark, check, Fuel, check, Compression
It might be worth a shot trying to start it at wide open throttle, you may have to disable any anti start mechanisms that prevent this. I had a low compression 18hp that would only start with the throttle open due to low compression. I lived with it till it flipped me off the back of the boat and did a 360 and tried to kill me. At least if you can get her running then the rings might loosen up a bit. Failing that i'd put a set of rings in.

 

[twocyclemania]

Re: 85 Johnson 2 horse - carburetor access

Update: I removed the exhaust cover and found the one ring farther back on the piston seemed to give a little when I pushed it with a small screwdriver. I'm thinking it's working as it should or somewhat. I had hoped that it loosed up from the solutions. I spent the past few days pouring solutions (including auto trans fluid crc knocker loose and penetrating oil) but I don't have any acetone) over the exposed rings. The top ring is pressed all the way in and does not move at all. There is no piston scoring from what I can see. I had hoped that the movement of the lower ring would give me a little bit of compression. The motor did manage to get it to give me very slight firing (first time) but that was it and it didn't happen again. I think the viscosity of the trans fluid helped to create a bit of compression and it was a one shot deal. I took another compression reading but for some reason it was even lower than the original 30 lbs. Should I keep on trying to soak the rings or remove the piston, hone, and add new rings? Any advice? thanks

 

[Bosunsmate]

Re: 85 Johnson 2 horse - carburetor access

Yes remove and see if you can clean up the rings without having to buy new ones. But new unworn ones would be much better.
You a just waiting good trans fluid etc if you keep trying JMO

 

[twocyclemania]

Re: 85 Johnson 2 horse - carburetor access

I even tried cola and that top ring is still stuck all the way in. I don't think it's going to release any time soon. Is there a safe way to remove the existing rings stuck as they are? I know rings will break without much effort. I'm inclined to remove the piston, hone,and replace the rings. Anyone think I should hold out longer or go with the replacement? thanks for all the advice!

 

[nwcove]

Re: 85 Johnson 2 horse - carburetor access

I even tried cola and that top ring is still stuck all the way in. I don't think it's going to release any time soon.

you tried what???

 

[boobie]

Re: 85 Johnson 2 horse - carburetor access

Nwcove, you never heard of using coke-cola to free a rusted bolt or nut. That was a trick they used years ago.

 

[boobie]

Re: 85 Johnson 2 horse - carburetor access

Twocycle, I think it's time to bit the bullet and tear it down. JMHO.

 

[twocyclemania]

Re: 85 Johnson 2 horse - carburetor access

I'm glad someone got a charge out of my using cola. This was the 'hail Mary' play. I had hoped the acid would eat up the corrosion/electrolysis or whatever is holding that ring. I'll give it a day or two more then I'm going with the recommendation that I tear it down. It's a low use motor and only one cylinder to deal with. I've got to see this thing run. thanks again!

 

[nwcove]

Re: 85 Johnson 2 horse - carburetor access

Nwcove, you never heard of using coke-cola to free a rusted bolt or nut. That was a trick they used years ago.

have heard of that....never tried it tho. but knowing how corrosive that stuff would be on machined surfaces, bearings, its just something i would not even consider for that application.

 

[boobie]

Re: 85 Johnson 2 horse - carburetor access

I never used it either. But some old mechanics in the model "A" Ford days did.