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Just managed to get a great deal on a 12ft parkercraft and an older(early 80s)7.5hp Johnson outboard,have painted the waka and replaced the plugs and put fresh fuel in the tank of the outboard,got her fired up and running but bit rough,what’s some other things I can do to improve the running of the motor?have googled a bit and seen that a new impeller and to change the oil in the bottom of the shaft is recommended??any other ideas for the old girl? Thanks team.
Wow she looks great. If it’s running but rough, the new plug could be suspect or you will need to flush the carbs and fuel line. Should of given you my other one to camo, that’s a fantastic job.
Do you know its history?
If not change leg oil and replace impeller for a start.
Without actually being there to hear it run it is impossible to diagnose anything but.
drain float bowls.
If it starts and stays running reliably after changing leg oil and impeller give it a good run in a bucket or on the muffs untill well warm, telltail should be warm and 6year old stream not 60year old stream.
Fuel mix should be 50/1 of fresh fuel and a outboard oil not a chainsaw/lawnmower oil.... mine seems to prefer 95.
Of that vintage it may have a mixture screw on the front with the choke and stop button....it can take a while to really get this dialed in so idle is reliable if it has been sitting or titued with.
Only adjust it after at least 5 min running at or near full load to clean the plugs and be at operating temp....once dropping to idle if slowly idle drops and or it 4strokes idle is too rich, wind knob clockwise (tighten) to lean out. If idle increases or surges and is ting ting tingy its too lean adjust knob out anti clockwise.
If all good get out and burn a tank of gas on the water( in walking or rowing range) some full throttle hours does wonders for old two smokes
Hardcase,download image is right way up.
Nice paint job
Also the tell tail has water pumping through it but not a powerful stream..
Yea considering she was BRIGHT orange it came up pretty good,Had it in at Kings marine here in Hamilton for a proper overhaul but rushed in today and grabbed it back as I want it up and running for opening day if it goes ahead that is..bloody lockdown..only thing I can see missing is the tilt adjustment bar thingy so won’t be able to hit reverse or the motor will end up in my lap..
If impeller has been replaced that is a concern, engines sitting unused and not well flushed can build up "salt" but is actually aluminium corrosion.Quote:
Originally Posted by The bomb
First poke a bit of 200-300p mono or a bit of tig filler wire or what have you up the teltail hole while running.....if a few pokes clears it you can rest a bit easyer that it is getting water but I would check thermostats are working and not blocked.
Haven’t replaced impeller yet as no parts available due to lock down,it’s on my to do list when things get back to normal,has a lean/ rich adjustment lever on the front by the choke so will give that a go once motor is warmed up,will try the mono trick as well,what oil do I use in the leg?
you could also try high octaine fuel.....my older 6hp merc came to life when fed the good stuff,as do chainsaws and mowers....the 98 from BP is great.
tilt bar thingy.....piece of cake...ball cock arm will fit.not at one end and bend the other....or any long enough bolt that will fit..... the angle of your dangle will make HUGE difference to how it pushes along under a load of guys n decoys.
possibly only one hole off bottom will work.
now you have boat n motor,the big weekend will be so much fun...I spend a lot of time and too much petrol (but we wont go there apart from to add oars are good) zooming around lake to stir up birds from the centre and picking up wayward decoys and picking of woundie birds....if the choose to dive rather than fly 3 times they die...
80/90 gear oil....standard automotive gear oil is fine.Quote:
Originally Posted by The bomb
Yea looking forward to not having to paddle the Canadian canoe this year, will keep that for drifting small streams,no dog this year either since the pointer cashed in his chips late last year..will give the 98 gas a go as well.
It's also important to check the compression. I have a 1995 Johnson 8hp and the top pot measures 120psi and the bottom 110psi. Closer they read to each other the better, with a minimum reading of around 80psi as a limit. My advice is to use 95 octane mixed at 50:1 and TC-W3 two stroke oil. I recently tried Silkolene Comp 2 oil from my race bike and found that it spat oil mix and smoked excessively at 50:1.
Only use TCW3 oil as it is designed for water cool motors not air cooled ones. Never seen salt water that I’m aware of, it has been some time since last started.
Replaced the gear oil and pulled and checked the impeller,blades look in good knick,got her back together and definitely pumping water better through her now,gonna mix some proper outboard 2 stroke oil instead of the stilhl stuff I used,have some for my bigger boat,really wanting to get to a lake and give it a good run to really see how it goes..starts second pull every time now..🤞will try the hi octane gas mix as well..appreciate all the advice..
I bought proper outboard 2 stroke oil and then mixed it will stihl stuff...LOL boat seems to work well with it,no excess smoke and starts good...15hp t stroke merc..... the 6hp 4 stroke merc was a dream to start on 91...not so flash on high octain but the difference at high end revs was measurable on gps....very measurable eg 3-5kmph more.
We will have to agree to disagree then.Quote:
Originally Posted by mimms2
Outboard oils only should be run in outboards.
It is less lethal to aquatic life and is less polluting.
It burns cleaner at lower tempratures to keep the plugs, pistons ,head and exhaust from carboning up.
Always mix to the ENGINES mix ratio not the oils, the oils 100 or 1000 to one rating is its maximum in engines designed for lean ratios.
If you mix 100 to one for a seagull designed to run 30/40 at ten to one it will seize its plain bearing in no time at all.
50/1 is the correct fuel for that outboard. A easy way to get your ratio is to double you fuel fiqure, and then move the decimal point to the left add a zero at the end and presto there’s your ratio. I.e 13ltrs of petrol double the figure =26ltrs move the decimal point to the left and viola there’s your mix ratio .260ml of oil.
Yep mixed it at 50/1,what’s the cause of this?had it running and warmed up in the tank and when I removed it noticed this..any ideas team?Attachment 133903Attachment 133903
Have you damaged the seal when checking the waterpump?
check leg oil level and condition for water or loss of oil.
The oil looks very black as if it is actually from exhaust but that is extreme amounts.
Mine does the exact same thing! Gearbox oil it isn't, so it has to be from the exhaust blowing through the leg/gearbox joint. Perhaps it's normal as we usually just use muffs for the Jap makes and no dirt bin?Quote:
Originally Posted by veitnamcam
Yea its extreme amounts tho.... possibly from running chainsaw oil rather than outboard oil.Quote:
Originally Posted by outlander
A tank or two of the wrong oil either way (saw oil in outboard or outboard in saw) is no major problem but continued use will drastically reduce engine life.
Sent from my S60 using Tapatalk
Well, that's a relief VC. It's a new (to me) motor so only ran it once and it was with Silkolene Comp 2 synthetic oil for two stroke bikes. I sure that's what caused it.Quote:
Originally Posted by veitnamcam
That might be it ,I used 2 stroke stihl oil,have some proper outboard oil for my 50hp so will give that a whirl,just replaced leg oil with new gear oil so don’t think that’s it.
The bin I’m using is only just big enough to fit the lower part of the engine in as well so might make it look like excessive amount of oil?gonna try an give the carb a clean tomorrow,might help?
It's got to be the 2 stroke oil, that's our common denominator. I've previously run both a Yamaha 30 and an Evinrude 115 on muffs and proper outboard oil with no oily evidence on the lower legs before.Quote:
Originally Posted by The bomb
Looks like that was the problem,rigged up the hose direct to the intake on the leg this time and no issues,there is 2 small holes at the lower front of the leg just under the seam where it bolts together which seem to be another exhaust exit along with the main pipe lower down..yeehaa ready to go for opening morning now..not that I’m holding onto much hope it will go ahead this year..
Not sure what you found...was it the small quantity of water in the bin, or the wrong oil? The two holes you mention are tiny in comparison to the amount of oil spewed.Quote:
Originally Posted by The bomb
Both I would say,used stihl oil for the first 50/1 mix, and the when I used the muff setup noticed the 2 small holes pumping exhaust,hadn’t seen them before as they were under water in water bin,also cleaned the carby out yesterday so it might be running cleaner now,think the small water bin might have added to the appearance of all the oil on the leg as I lifted it out it would have picked it up from the surface..
Will give the proper outcome oil a go tomorrow probably
I cant count the times I have been told about a fire on a boat when its just a OMC ( Outboard Motor Company) starting up. I do know the the OMC were absolutely notorious for over oiling on start up. A system designed as a safety factor for the motor. Yeah rite. Certainly on the V R O ones.
All good she is running sweet now,think the wrong oil was the main issue along with the small water tank I had it in,bring on opening morning!!!
i may even come over one arvo and join you
