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1966 johnson 9.5 mq12a

just picked up this motor , started going over it , good compression , clean , paint a little beat up , looks like someone put new points, coil s in it , my question is motor seems very loose inside case , it moves all over inside case , is there a mount broken or wore out , you can put one hand on flywheel , whole power head moves very easy , even turning throttle handle whole engine moves ? if its a mount can you still get one ? how hard to change ? help
 
update , front mount was in pieces , tore it apart today , what a job , I picked up this motor at yard sale 50.00 very clean , guy said had tune up last year , runs good , checked spark , top good spark , bottom no spark took flywheel off , everything is new , even wires , cleaned gapped points , got good spark , been soaking oil in cylinders last 2 days , top cylinder 95 psi bottom 125 , everything I read said look for 75 , drained bottom end oil , very clean looked like new oil , pulled water pump , impeller looks old , ordered new one , I restore lawnboy mowers this is my first boat motor , cant wait till parts get here
 
Since you have the hard part done, may I suggest you go the rest of the way and replace the boot around the shift rod? They are very prone to failure, and when they do, the motor won't run worth a hoot with the hood on.

Your huge difference in compression readings demands further inspection and diagnosis on that too.

You are spending far too much in time and money to build up something that won't run right when you get done.
 
no I didn't pull head , I will check flywheel , heel gap , I ordered mount , impeller , shift rod boot , plugs , parts will be in end of week , ill keep you posted , the older guy I bought it from said he had the tune up , and carb done , and it always run good , so far all ign parts are new , I haven't even touched carb yet , I have so many parts laying around , one thing at a time I guess , ill keep you posted , thanks for all the help
 
I have this exact same motor, so I will follow this thread. I have only run mine in a bucket as I'm doing a refurb on my 1963 LoneStar 1448 V-hull.

CMOS
 
update , got the motor mount and other parts , got the motor mount installed , case all put back together , what a job , put the new impeller in , will put bottom end together this weekend , a going to re compression test it , got all oil out , got to check and set timing , I pulled carb, everything looks new,cleaned blew out , iam almost there , I cant wait to hear this thing run , oh I got to get new pull rope , looks rough , hope to bring this old girl back to life
 
couldn't wait [put it together , did timing with volt meter , first time for me , went well, good video on youtube , re do on compression test , all oil cleaned out dry cylinder , first top 87 bot 90 second 88 91 third 88 90 that sounds a lot better , all that oil really messed things up , got bottom end in , everything seemed to go good , checked spark , good , hooked up fuel tank , primed , one pull she started and ran great , pumping good water , really sounds good , shifts smooth , I like this motor so much my new Johnson coming off boat, cant wait to hit the water , that project went so well iam looking for another , thanks for the help guys
 
Now that's a happy ending! Congrats on the good work.

kimcrwbr1 - I have heard others say to NOT fuel starve the engine when done since a 2-stroke needs the oil in the fuel for lubricant. Thoughts?

CMOS
 
Hat's off to you pabiggun, not many people could pull off such an intimidating job and still be sane. I've done it on lots of those motors. After awhile it gets easy.
 
i have been repairing , restoring ,buying , selling, lawnboy mowers, and john deere tractors for years, i do about 50 mowers a year ,5 to 10 tractors ,i really enjoyed working on that old Johnson motor , i will be adding boat motors to my side business i have been reading repair manuals and learning a lot from this site ,want to thank everyone for your help
 
CMOS---Running a 2 stroke out of fuel when done is the best thing you can do to keep the carburetor clean.--------------Those that say otherwise simply do not know how lubrication of a 2 stroke works.----They simply do not know what happens to the oil once the fuel goes through the carburetor !!!!!!!
 
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