Re: '87 Johnson 70 Cylinder Question
iF YOUR THAT FAR INTO IT ALREADY,YOU GOT TO DO IT RIGHT ,BORE IT TO NEXT SIZE ,WHICH SHOULD BE 20 OVER,UNLESS THE GAUGES ARE DEEPER. i THINK YOUR TALKING ABOUT THE SIDE PLATE ON THE PORT SIDE OF THE ENGINE.tHAT SHOULD BE REMOVED AND ANY CARBON,SALT ETC CLEANED OUT.yOU SHOULD DEFINATLY CHANGE THE BOTTOM BEARING AND SEAL ON THE CRANK,USE ALL NEW BEARINGS. tHEY ARE CHEAP,EXCEPT FOR THE TOP AND CENTER,UNLESS THERE IS A COMPANY THAT NOW PROVIDES THEM AFTER MARKET. i USED A COMPANY CALLED PRO MARINE,DONT KNOW IF THEY SELL TO INDIVIDUALS,BUT I'M SURE YOU CAN GET ALL YOUR GASKETS ,BEARINGS ETC FROM SOMEONE. PERHAPS IBOAT,I HAVENT LOOKED. I PERSONALLY LIKE WIESCO FORGED PISTONS,I WOULD BORE THE ENGINE ALL THE SAME,MAKE IT NICE AND UNIFORM.AFTER YOU GET IT TOGETHER,IT'S POSSIBLE YOU MAY HAVE A IDLEING PROB.THESE ENGINES SOMETIMES NEED CHANGING OF THE AIR JETS.I DONT RECALL THE SIZING ,BUT I'M PRETTY SURE THEY NEEDED TO BE SMALLER.IF YOU SPEND THE LITTLE MORE TIME AND MONEY,THAT ENGINE WILL LAST ANOTHER 20 YRS NO PROB.OF COURSE NOT COUNTING LOWER UNIT AND ELECTRICAL .CHANGE YOUR IMPELLER EACH YEAR CHANGE GEAR OIL OFTEN ,AND YOU WILL BE OK.HONING DONT DO MUCH OTHER THAN TO GIVE YOU SOME NEW CROSS HATCHING,WHICH SHOULD BE DONE AFTER A TRUE BORING THAT WILL MAKE THE CYL,ROUND THROUGHOUT AGAIN,BRING IT TO A MACHINE SHOP THAT DOES OUTBOARD STUFF AND ASK THEM TO MAKE IT READY TO ASSEMBLE.
