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Hi Guys could you help me with a Johnson 3 hp jw-18 1963 issue?

Drunkenbum

New member
Hi
Thanks for reading i am totaly new to outboards but built enough 2 strokes to know my stuff

Story so far
i was given a small boat and outboard last week the engine is a Johnson JW-18 and is in very good looking condition ..so i changed the plugs for NGK B7s cleaned out the tank and carb ( they were spotless in inspection ) mixed oil 50:1 ( 100mm oil to 5ltr petrol) put it in a vise ,fired her up and she started. I gathered that it needs water to cool so litraly had it running for 5 seconds brung revs up once then killed her

So onto the water
got her going and after about 30 seconds she died ..good look round striped carb again and and noticed the air valve on filler cap has to be open ( slaps head) ..anyway starts her back up and i am off ..bit splutery so sorted mixture out and she was fine ..untill i hit some weed and she started to struggle ..now i am not a boater so cariied on thinking it would clear .it did not ! and then Died and will not start again:-( dident feel hot or smell hot so hopfully i have not cooked it

So guys i have no bought a repair manual but was wondering what your thorts are to what is wrong

thanks for reading

Jay
 
Not any help with why it won't restart but

Currently recommended plugs are Champion J6C. NGK N7S may be just a touch cooler but about the same as J4C that were originally specified.. Id have probably used B6S if the Champions were not avaialble but splitting hairs probably

That 1963 motor has plain bearings, no needle rollers at all , therefore use 24:1 fuel mix with a TCW-3 oil

Dont run it out of the water at all or you will wreck the water pump impeller. Its a good idea to fit a new impeller anyway on a "new to you engine" if you don't know when it was last changed so put that on your "to do" list.

Also check the gear oil.

As for current non starting. Check the compression before going any further to be sure you have not over cooked it beyond economic repair.
 
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Not any help with why it won't restart but
Check the compression before going any further to be sure you have not over cooked it beyond economic repair.

Thanks Vics i can feel compression on the pull...Bloody hell i suspect i have cooked it now :-(
Are rings and piston's not avalable anymore for these old engines? as for mix 24 ML of oil pr ltr ?? thats seems a hell of a lot.planning on taking exaust off you can usaly see if its cooked by looking at the rings through the port calnt you?
 
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It is a 1963 model.-----24 parts gasoline and 1 part oil is the mix ratio.
:( sounding like i have done it in then what a shame thing is it had the ratio on the back put in pints so must have got my maths wrong to metric....gutted !!!!! its most certainly that then i suspect ..its not Seezed though so i have a chance ?? can you get rings for these in the uk?

Thanks for you input guys bit embarrassed and gutted at the same time
 
Thanks Vics i can feel compression on the pull...Bloody hell i suspect i have cooked it now :-(
Are rings and piston's not avalable anymore for these old engines? as for mix 24 ML of oil pr ltr ?? thats seems a hell of a lot.planning on taking exaust off you can usaly see if its cooked by looking at the rings through the port calnt you?
24 :1 is 42 ml oil per litre petrol. A tad more than twice as much oil as 50:1

Do the compression test and report your readings

Both plugs out and pull it over 5 or 6 times at least to get a maximum reading on the gauge.

Pistons and rings are available according to the parts lists on Marine Engine

I buy parts from Oakley marine ( aka Outboards direct) in Brighton. http://www.outboards-direct.co.uk/ If you fill in an online enquiry form someone will phone back to check the details.

Users of the YBW.com forums in the UK have also found Wills Marine in Kingsbridge, Devon good for parts.
 
For what its worth, folks, I have no less than 100 of these little twins between my own and those I have repaired. For some 40 years now I have been using Amsoil pre mix with strictly non alcohol fuel. This full synthetic oil is rated for any outboard application at 100:1. However, not throwing caution to the wind, I mix 64:1. That's 2 oz per gallon. This is only in non needle motors, others at 100:1......this is what works for me and my customers. Had one failure however, but I tracked it back to a plugged pickup screen for the water pump. The guy was scaling panfish on top of his outboard testing barrel. Boy, did he feel stupid. I have 2 resorts in remote NW Ontario, and have used Amsoil at these ratios for 40 plus years. Our main motors are 9.9 and 15 hp OMC's with also twin 25, 30 and 35 hp OMC's for the bigger boats. If you can't move outboards around by hand, they have no place in the bush. 4 strokes are just too heavy and bulky. At these ratios we are running very clean anyway. My 1967 Evinrude Fisherman has 4000 plus hours on it. I started guiding for my Dad with it when I was 10 years old. Since 1980 it has been running on above mentioned mixtures. Amsoil now has an excellent oil called Saber pre mix for hand held equipment, which includes chain saws and weed eaters. I have run chain saws in logging and firewood for 48 years, only hurt 2 saws to the point of needing overhauls. In both instances it was because of failed crankshaft seals, clutch side. I always do my air cooled equipment at 64:1, however, but I love the Saber, it produces excellent performance with very minimal odor. Many days I spend 4 hours with a chain saw running in my hands. These are bigger saws too, nothing under 70cc. My big boy is the Stihl 880 magnum which is 124 cc. Still running perfect after 10 years of cutting red oak firewood with a .404 full chisel. I will never run any other product than Amsoil in my outboards or power tools, so I can't speak for the ratios of the oils that were engineered when they set recommended ratios in 1963. Besides all this, I HAVE TO SPEAK THE TRUTH, I GOT A BAD MEMORY. Go ahead and blast me, but let me ask you one question first. Why do you want to argue with someone that's right?
 
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So you ran it all clogged up with weeds and what-have-you, starving it for cooling water until it overheated and seized up solid did you? Hellava way to get to know your stuff about outboards too! :)

Anyhow, lesson learned. That hot... best to replace the head gasket regardless of what compression you might have, then tighten every screw, nut, bolt you can find on that powerhead... that much heat would loosen all of them.

Also replace the water pump... it's about had it.

What has been told you by other members about the 24/1 mixture... that is absolute gospel... listen to them! Otherwise you'll be having some expensive parts turning blue!
 
Ouch! So you won't go fishing with me at 64:1? I got a spare motor.......but seriously, I'm in this business to make customers happy, not destroy motors. I give a full one year warranty on all my repairs..........if my operating instructions are followed. Everyone gets a free quart of Amsoil to get them started, I have a list of references that will blow your mind. Our subject 3 hp, however may not have been as severely damaged had he been running 64:1 Amsoil.
An injector line broke off first trip up the portage in Ontario just last spring. It was almost dark. Didn't catch oil drip. Freighting in with 1987 Merc 115. WOT, it slowed to a stop.......scarry stuff. NOT a running out of gas type stop. I've been running outboards for 55 years. The motor restarted and ran another 3 or 4 minutes, froze up again......ouch. Pulled cowling and looked with flashlight.......oily???? Turned around and back to landing with the kicker motor. Put freight back in truck, boat on trailer, back 30 km to town. Grabbed a motel. Next morning I found the brittle plastic injector line completely broken off at the injector pump. To the little marine shop in town, I know the owner well. He had to run to Winnipeg for the day but left me a few tools and a compression tester. Shop was closed for the day. Hooked up all new lines, added more Amsoil Injector pre lubed cylinders. Compression 100 to 110.......ouch! Test ran on Eagle lake, ran strong. Headed back up to the river......30km run, perfect.
You tell me any other oil could pull this off? No way in God's green earth. Its time to upgrade the Gospel.......this is new technology and it can be applied to old equipment. When I began operating outboard motors.........the same ones I still have here in my collection........the manufacturers asked for 30w motor oil at 16:1. You spent the day trying to troll in a cloud of smoke, brother. The only break you got was when you stoped to change spark plugs.
 
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Any way.......I don't care for this new technological marine industry, I'm gonna retire soon. I run and I love the "old stuff". I work on this new stuff, but the romance and love is missing. They used to make 100 horsepower outboards with no transmission.....direct drive only. I had 'em, they required a bit of common sense to operate. Mixing oil with gas is almost a thing of the past. Today's world is "idiot proof" and personally I don't like where its going. If you can't accurately mix 2 ounces of oil to 128 ounces of gas, you should go buy an injection motor, or 4 stroke. I love my old stuff, and live my life by it. I want it to last until my grandchildren have it taken away from them by the government. My customers respect me for my stand, if they don't then they are out on their own. Dealers around here Don't even work on pre 1990 motors anymore. Me and a few others that try to repair their own stuff, are the only game in town. I will not steer them wrong. My ratios with Amsoil are not on theory, they are proven fact and acted out on years and years of experience. Show me one other individual with my years of experience using Amsoil 100:1 two stroke oils in almost any conditions........including 12 hp Ski Doos, and I will step down from my soap box and crawl under a table. I still run my 12.3 Olympic to remote Ontario for ice fishing. Do you think I want to let go of the machine I built with spare parts 35 years ago? I don't want to go 90 mph on the ice. 30 is just fine.....pulling a sled with full fishing gear, plus a passenger. If I get bogged down in slush, I don't need 4 big guys to lift it out of the slush, I do it myself. Some elderly gal asked me while watching the snowmobile races on open water a few years ago.......she asks, "how can they run a powersled on water"? My answer: "You put a 200 horsepower motor on a 600 lb. machine......and you can do ANYTHING"! Hah...........for each his own. I'm at 64:1.......sorry.......the record speaks for itself.
 
timguy so i am best using 64:1 mix then ?? lol

anyway guys thanks all for the advice i have learned my lesson just waiting for repair manual to come today and then i can do a compresion check
 
Yes its about that price but BUT it looks just like any other fully synth 2 stroke oil and as that i would use Motul ..i havent had time to look properly yet so i will post my compresion findings when i get round to it its not Seized by the way it never seized and wasent red hot ..i hope its the points tbh and now i have the repair manual i can get at it
thanks for your input
 
Look to see if the paint is discolored on the head. A little discoloration is normal on exhaust cover, this will also indicate how hot it got. Maybe it was discolored already.
Regarding oils......I have no recommendations or faith in any synthetic other than Amsoil. My experience is exceptional on this oil, especially with application in regards to older outboards. If you should go 64:1 it is only recommended by yours truly, that you use the 100:1 pre mix, or the Saber line. The Saber is only for pre mix as well. Why, because injection systems will inject much more oil than is needed. They have no brain to decide how good the oil is, if its contaminated, or if its even a synthetic. Synthetic oil qualities will vary and I have no experience, nor do I recommend blended synthetics. A key to 64:1 is also using top grade fuel with NO ETHANOL.......NO ALCOHOL. As I stated earlier in this post, I want my equipment to last. 24:1 mixtures were recommended for your motor long before 2 stroke oils were barely out of their infancy. Oils are improving over time, and we must consider that before we use antiquated recommendations. Amsoil is the VERY FIRST 2 stroke synthetic and was formulated in the late 70's. They are constantly testing and improving it. Many tests on 2 strokes have been conducted at ratios near 200:1.....at all motor speeds and loads. Some have failed, but at these ratios some failures were expected.
 
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timguy so i am best using 64:1 mix then ?? lol

anyway guys thanks all for the advice i have learned my lesson just waiting for repair manual to come today and then i can do a compresion check
Dont forget not only does your JW-18 have plain bearings but there are no crankshaft seals.

It relies on an oil film in the bearings to form a seal.

Insufficient oil means no seal
No seal means no go

at least if it wont go you wont do any damage through lack of lubrication

100:1 may be Ok in more modern engines but your Johnson deserves better treatment in its old age


Never seen anyone praise Amsoil before
 
If I can figure out how to post a video, I will show you one of my 1953 5 hp Johnson's running in my barrel. 64:1. It has been operated with Amsoil 100:1 for 30 years. You will see it running for 3 hours at a very slow idle, running with my hand on the cylinder head for a count of ten.....no gloves, minimal.....very minimal smoke. You will see the water stay crystal clear and clean. I can throttle up and without hesitation, shoot water over the top. Here is my question: What the he#% have the engineers been doing for 66 years? If they are trying to build a better outboard, more reliable, more efficient, easier to service, lighter, well then they have failed. There has never, ever been a crankshaft leak, or even the telltale lean "burp". Now this is solid, reliable, practical engineering. The engineering apparently allows for a certain amount of outside air to enter the seals. This is a given and calculated part of the mixture. If you ever needed an outboard that you could count on to get you out of a remote location in foul, cold, nasty weather. This would be my choice, not a 65 year old Yamaha.
 
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How about breaker points? How many outboards can you clean and set the points without pulling the flywheel? How many fuel pumps and gas lines does this motor have to fail? How about the neutral feature, just flip the lever. They engineered the fastest jet in the world in 1962......the SR71. What's happened to our brilliant engineers? Seems they focus on making equipment more technical and expensive to repair, rather than bulletproof, practical, simple, and repairable. You can still buy almost any part for this sweet little 5 horse. Think for one second that you will be able to buy parts for the 2018 Yamaha in the year 2084? If you guys keep running 16 and 24 to 1 in these old outboards, the Government WILL take them away from us sooner than you think. When I'm out on the lake and fishing with my vintage motors, people are amazed. They are not "scolding" me for "polluting" the water. They are saying, "WOW! DOES THAT RUN SWEET"!
 
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No, I'm not turning my back on today's equipment. I fix 'em all the time, but I can't help but see the obvious. There are simpler ways to create economy, power and reliability. Our engineers and manufacturers are focusing on complication and money. They need to insure a job for themselves in the future. For instance the CVT auto and truck transmissions......a Kevlar and rubber belt, are you kidding me? I got that on my 1969 Ski Doo.....but it is run by centrifugal weights and simple. These replacement CVT tranys are supplied only to select dealers with parts needed for overhaul not available to even the best transmission shops. Clutches are controlled through floodgates of electronics and sensors that often fail. Fluid is 12 bucks a quart. The government or some hacker can shut you down from a satellite. The future is bleak. Who needs a 400 hp outboard if the sattelite says stop........you are down to a paddle with a 2 ton boat. Don't buy gas at "pay at the pump". This is just the tip of the iceberg.
 
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