1984 Johnson 70hp Triple "Tear Down" And Diagnosis ( Johnson / Evinrude 55, 60, 70, 75 hp )

Pretty much is what the title says :) AND trying a few things over here to raise the state of my art on video's in general

[@johnzizik]

Great video for those of us who have these old Evinrude outboards. Mine is a 70 hp. I’m taking it apart right now due to no compression in cylinder 2. This was exceptionally helpful. Thanks so much!!

[@htssoutboardsboatstrains9784]

Certainly we can start a conversation on these , I have two more in the "works", I'm glad these can help. Trying to have them as a reference for.....me ( selfishly )

[@joeyherring5942]

What did you find? Mine has 30 psi compression on 2. 120 on 1 and 3. I'm in the research stage, but I can't see anything that can cause something this drastic, short of a hole in the piston. I haven't scoped it yet, but that's next. Turns over smoothly, no rattles.

[@johnzizik]

@@joeyherring5942 For mine, when I tore it down, it appeared to be a lack of gas and oil mixture (my fault). I had the head re-bored and honed and I’m getting ready to put new pistons, rings, gaskets, et al into it.

[@joeyherring5942]

@@johnzizik I opened mine up yesterday and found the same issue. #2 cylinder is fried. What did it set you back for the rebuild parts ($) and the rebore. I'm deciding whether to keep it or not. Thanks for the reply.

[@johnzizik]

@@joeyherring5942 The bore was $50 bucks a cylinder, pistons and rings, etc. are about $500. Repair parts are ridiculous right now, however, buying a used motor is even more ridiculous. Good luck.

[@johnhicks735]

I recommend getting some of either hondabond 4 gasket sealer sealant to put the gaskets back on with.,or some yamabond 4 let it dry totally before reinstallment.,or installation process of the new parts. From after removing the old parts out first procedure steps. So that already puts you in the getting the sealer sealant for your new gaskets.& Next the honing out those pitted.& Scratched up.& Scored cylinders walls individually before installing everything back into the outboard motor for using again.

[@ls2005019227]

I've had a Johnson 60hp since 2007, and just recently picked up another for my 14 & 15yo boys who are building a play boat. We've been researching for the teardown, which is why YT recommended this video......the beginning sounded familiar; & lo/behold, it's one of my favorite YT chainsaw friends, @afleetcommand!! I'm off to see what else you recorded for this motor. Thanks!

[@craigtimmons3468]

WELLLLLLL! The Blueing on the crank was the second clue, you even stated it looked dry and had been a little hot. Hopefully that block will clean up. Great investigative work.

[@htssoutboardsboatstrains9784]

Getting .020 over pistons for that one like I did the first. :)

[@vinhphan6738]

Thanks so much for posting this video.

[@johnhicks735]

I'd get A set complete set of hone tools to use for that outboard motor to. Along with cutting oil.&:some stp with bars stop leak in it to. For whipping around inside of the cylinder with for reinstallment of the new pistons.& Rings. It'll help with the break in process to with the new pistons.& Rings for proper wear.& Seating inside of the cylinder walls of each individual cylinder to.

[@mumbles552]

I've seen where people miss that hidden nut at the rear and break the intermediate plate by forcing the powerhead off!

[@joseluisalmonte9016]

Envitame para tu pais arreglar motore fuera de borda

[@tomhsawyer2011]

Thinking of powder coating my 70’s . I will let you know if a problem from heat but I really doubt it. Might have to learn to cast aluminum. Parts getting difficult.

[@htssoutboardsboatstrains9784]

I just grab them when I see them for cheap. All fresh water here and it's not unusual to see them not running for $100 bucks just to find the reason they aren't running is the fuel lines / pump just sat too long.

[@joaquinvidal1984]

Good job 👏

[@johnhicks735]

DIY your own ethanol free fuel types to use for running in them.& Other things to like lawnmowers.& Weed eaters.& More. That are known as 2 stroke small engines.,or 2 cycle small engines.

[@jonm7463]

Hi great video. Are you in the upper Midwest ? I'd like to buy a suspect engine,but don't know if I can do a full rebuild like this video.

[@htssoutboardsboatstrains9784]

North east. IF u have a decent machine shop in your area for the bore & hone you can do this. :)

[@cabdulaahicabdiyamahasomal3550]

❤❤❤❤❤

[@michaelmurrietta2263]

All evinrude and johnson have that pin on the crank case and they are removed from the rear

[@banditdarville.]

Hi, Thanks for taking the time to make this. I have a question though, it looks like the engine has 'wet liners' so do you remove them and send them for rebore, or are they bolted in? so you just send the whole block for rebore? Thanks in advance.

[@htssoutboardsboatstrains9784]

They are interference ( heat ) fit. So I guess it's theoretically possible. There is a shop in Canton NY that claims to re-sleeve those as when they get hot the center one sometimes gets loose. Me? I used over sized pistons and had the block bored/honed to fit the pistons. It's pretty easy to find .020" over pistons. Even .030" are available. Cayuga Performance in New Field NY did the work, did an EXCELLENT job too. Standard bore is 3" and he nailed it at 3.020"

[@banditdarville.]

@@htssoutboardsboatstrains9784 Thanks very much for the info, happy boating.

[@RedfishCarolina]

I have a 1980 70hp Evinrude that was bored 030, its etched on the piston tops, so I assume that's what that means

[@johnhicks735]

Fast conversion names.& Terms knowledgey for saying 4 stroke small engines./ Is 4 cycle small engines.& 2 stroke small engines./ Is 2 cycle small engines.,,or outboard.& Inboard motors for boats.& Etc. Use on water ways.& Large bodies of open waters to.

[@dougfloyd7342]

Hey like your videos. question: I have a 1986 3 cylinder 60 hp outboard, it has been sitting for about 3 years. the Flywheel would not turn so I removed spark plugs and added some sea-foam creeper and let it set in upright position for a couple of days. Was able to turn flywheel with wrench and pull bar (worked back and forth until it made a full turn. It turns but seems a little sticky at one certain point while turning. Installed new starter & solenoid & battery also new thermostat (old one was completely closed but last time out water was coming out from water pump line. Tried to crank but starter engages but will not disengage unless I turn flywheel with wrench. I guess what I'm asking is there major damage internally and is it worth trying to fix? Any help would be greatly appreciated. Thanks in advance!

[@gabriliru9665]

Hi, compliments for your video! I have the same engine as yours, my mecchanic found some water inside of the cylinders, the middle one and the lower one. Engine head gasket is okay, so the meccanic said the water is coming from some other source. So my question to you is, what do you think could be the problem? Thank you in advance.

[@htssoutboardsboatstrains9784]

I've seen some where the sleeve actually would move & let little water in. But that also was accompanied by a funny knock. Usually middle cylinder. Another place a little "less likely" simply is from the exhaust water jacket coming back in when the motor shuts down. Obviously w/o rpm's there is little of no pressure so it would be more than a "leak down" back into the exhaust port. THAT would be the "preferred" issue for sure.

[@gabriliru9665]

Thank you for your answer. To fix the problem you mention, I have to unmount the engine completely? Is there some gasket or oil seal to replace? Thank you in advance..

[@htssoutboardsboatstrains9784]

@@gabriliru9665 I would pull the motor and then have access to the cylinder head, head gasket and exhaust plates. If the center sleeve has moved you have to do that anyway. Not many places have the ability to fix the sleeve issues. There is a machine shop in northern NY that claims to be able to re-sleeve one of those, but who knows. At that point I might find a block and fit new pistons as I did on the two project motors i did for this channel.

[@gabriliru9665]

@@htssoutboardsboatstrains9784 Thank you very much. I was thinking it would be easier...I'm not a mechanic, I wanted to try to unmount the engine, but, to replace sleeve and pistons...it's too much. I give up. Im going to sell the engine for spare parts. I'm sorry beacuse it was an old engine, I was attached to it. I want to thank you for your advices and for your time.

[@austinlobue5627]

Will a 1989 70hp rebuilt power head work on my 1978 Johnson 70... I'm trying to do pistons/rings/ gaskets on my 1978 but can find only parts I can find are from 1989-2001...

[@htssoutboardsboatstrains9784]

Head gasket for sure won't fit. I think a lot changed in 1986. Also wrist pin bearing and a bunch of things. So what works on a 78 might work up to the 84/85 version. Best resource is to look in marineengine.com and check the part numbers.

[@markchristopher6248]

I have a 1984 70hp Just like in your video I replaced the top seal, but i screwed up my roller bearing with the drywall screws getting the seal out Do i have to take the hole engine apart or will it come off from the top? Please let me know i can't seem to find a video

[@htssoutboardsboatstrains9784]

Have to take it all apart as there are "pins" to hold the outer race in place. Sorry :( BUT really not the end of the world. If I can do it you can. :)

[@storyoc]

i want one of those crankshaft lift things that attaches to the cherry picker-any links???

[@htssoutboardsboatstrains9784]

prolly not I made that one

[@storyoc]

@@htssoutboardsboatstrains9784 ebay get 50bucks for a lift that attaches to the 3 flywheel bolts-i guess ill rig something up-

[@captainchrisfishing]

Would you be interested in rebuilding a 70 hp johnson for me

[@htssoutboardsboatstrains9784]

depends on where u are and how fast you need it :)

[@michaelmurrietta2263]

Just bore one hone others

[@htssoutboardsboatstrains9784]

Got all new stuff .020 over

[@zexsir]

Ever done with when all cylinders are .020? Just bore your bad cylinder to .030 over?

[@michaelmurrietta2263]

Can do if it clears up for 30 over remember it's a 2 stroke it won't be out of balance it will run

[@htssoutboardsboatstrains9784]

@@zexsir nope usually I just do them all. I've had folks request I just do one. If I have all the time in to tear apart get the machining done etc. I'm doing all three

[@135-j]

Do you have any tiller arms for sale for these Johnson motors

[@htssoutboardsboatstrains9784]

No, be fun to have one though :)