1974 Johnson 50hp Stuck.

[Chrisravosa36]

Ok thankts scott, Im just wondering if Timing will be an issue, or if it easy to take car of? I dont know much about the ignition systems at all...

 

[flyingscott]

Timing is much later. What I do is take lots of pics of the motor before you pull it apart. I will take the whole throttle and assembly out as one piece. Disconnect the magneto rod from the magneto and the shifting rod from the shifting. That way they come out still connected. One trick is get zip-ties because when you take the big linkage off there is a spring in there. When it comes loose put the zip ties to hold it all together. That way when you put it together timing will be easier but that is a conversation for a much different day you are not even close to that.

 

[flyingscott]

Also don't unscrew anything from the linkages leave it as is.

 

[Chrisravosa36]

Haing trouble taking off the head, I took all the bolts off from under, took about 3 hours to remove everything necessary, flywheel actually came off easy. Anyways, the powerhead is off, but it is like there is something holding it down, the backside lifts about an inch (sparkplug holes back side), but not the front, it looks like there is the powerhead, a gasket, this orange aluminum block, a gasket and then the exhaust housing, any tips? I followed everything in the manual, and it said nothin about this, in totally I removed 8 large bolts, 2 small bolts and a nut and washer.

 

[Chrisravosa36]

There is a seal in-between the two metal plates, but it wont come apart....Im not sure how I should attack this, but Id like to get the head off today. Any help??

 

[racerone]

????----The part with the red primer does not need to move to get the powerhead off !

 

[Chrisravosa36]

Yes, but it did, there was one nut holding it on, should I put that nut back on? I tried getting it off before that nut was off, and it still wouldn't come apart... Im sure ive got all the bolts off, because thats what it suggested in the manual.

 

[racerone]

????---The part with the red paint does not need to come off to remove the powerhead !---Post a picture of all the bolts / nuts you have removed in order to get the powerhead off the mid section /. exhaust housing.

 

[Chrisravosa36]

Alright I will do that in about 3 hours when I get home, just to give you an idea, I took all 4 bolts off the left side, and all 4 off the right, and the back bolts on the back of the motor, but I will still take pics when I get home.

 

[Chrisravosa36]

Those are all the bolts I took off holding down the powerhead

 

[racerone]

There should be 4 bolts 1/4" ( same length ) that mount the cowling to the block / cylinder head.---------8-5/16" bolts and one nut ( 5/16" fine thread ) that hold the block down to the exhaust housing..--------

 

[Chrisravosa36]

I did not get 1/4 bolts, where did you find those?

 

[racerone]

???------I have found those 4 bolts on everyone of these motors I have taken apart.--------Please read post # 91 a few times.

 

[Chrisravosa36]

Misread it, yes I took those out and they were not pictured, my fault, thanks for your help!!! I got it apart, opened up the head and cant seem to get the four connecting rods bolts out, is there a special tool for this? A socket wont fit in there, and I dont have a wrench that small, any tips??

 

[Chrisravosa36]

FINALLLLLLLYYYYYYYYYYY!!!! Its unstuck!! Took the wooden bottom part of a hammer, put it in the center of the cylinder, and him the top of that hammer with a sledge hammer, it freed up pretty quick! Turns out there was just a little amount of rust... most likley I will need a new crank though, because this one is very stiff, also there is alot of patchy carbon buildup on the walls of the cylinders, I did not see any scoring on the walls of the cylinder. Im am also thinking of replacing the rings, I was unable to take the piston off though. I went and bought the right socket, but they were really stuck, so I had to get an adapter and that snapped because of the major torque... Is 1200 grit sandpaper to gritty to clean the walls with? or is there a better way to do it? THANKS FOR EVERYBODY WHO HELPED SO FAR:hail:! Hopefully I will be able to update you tomorrow with the crank out.

 

[Keyboardman]

Good Luck finding a new Crankshaft for that engine. : ) If you want to part it out let me know!

 

[Chrisravosa36]

I found actually alot of used ones, 71 - 76 50hp were the same

 

[gm280]

I found actually alot of used ones, 71 - 76 50hp were the same

Oh yes, if you look hard enough there are parts in some unusual places. But hang in there and post your project engine progress for everybody to see. That is how others learn things and can follow along with you. :thumb:

 

[flyingscott]

Take the bearings off before you decide you need a new crank. The bearings being stiff could be from old oil may just need to be polished up a bit.

 

[Chrisravosa36]

Will do. I'm having an issue getting them separated from the connecting rod, they are VERY STIFF!! I found the right socket for it, but I have to use an adapter to a bigger wrench in order to get close to enough torque to move it, and the dam adapter broke, bought 2 more and they did to, is there a special tool for this?