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1984 Johnson 4hp Seahorse general informations needed

haha Looks like I was wrong and the gasket is fine I'm going to go get an exhaust cover gasket and powerhead base gasket today
for now here's a picture of under the exhaust cover, Looks pretty good, particuklarky the water circuit. I assuming he little rubber 'rod' in the top right hand corner is another factory installed 'water restrictor'
I guess even if there's nothing amiss on the top end here at least i will know that which should provide some peace of mind.
 
Carefully press on the rings with a phillips screwdriver They should spring right back. Looks good actually, Do you have a compressor to blow any chunks of crap that may be lodged in the water circuits?
 
No compressor sadly. Working in my apartment!, the water circuits look quit clean. there is a inch or so long rubber rod in the top right of the exhaust picture, you can just see the end of it, hard to imagine it wasn't supposed to be there!
Got the bolts off to remove the power head though it's not being obliging yet
The exhaust cover came off really easy.
Used a bamboo skewer to press on the rings they seem to move freely
 
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It is in the parts diagram it is called a metering rod. These motors do not have a thermostat so it meters the water so the engine come up to operating temp at the head.
 
Cool, I'll give it a little clean, it's pretty well perfect already. The only potentially problematic looking bit in the water circuit so far was that bit of solid gunk at the bottom of the head
 
I was looking at heads on ebay and that is a common area that gets stuffed up. It should run just fine once yopu get it back together. I like to test the water pump before installing the gearbox. Just attach a socket and extension to the driveshaft with a chunk of hose and stick it in a barrel and spin the driveshaft clockwise with a drill the water should gush out the water pump?
 
hmmm interesting, the top grommet is COOKED, likely from the overheating..not exactly looking forward to another trip across town, found an $18 price on it. Yeesh. tiny little rubber thing, some crud in the water ciBottom o' head.jpgtop o' leg.jpgrcuit too but not plugged
 
I use a sharp wood chizzel to clean the old gasket off and brush a real light coat of permatex aviation gasket maker on both sides of the new gasket and snug the bolts down evenly then just give them a extra tug. If you try to torque to spec your likely to break the old bolts.
 
Cool , but I forgot to get a new grommet today and I already dropped $42 on this engine today, that'll make it $60 on this &^*& job. ah well, Too bad it's a short shaft!! haha
Anywho I tried the drill-hose-bucket idea, the pump seems to be working well, gushing out water, gasket scrape.jpgthanks!
here's my ye old purpleheart scrap gasket scraper!
 
yeah I might have to do something like that, which is too bad as when it runs well it pushes my boat well , is nice and light, has forward and neutral and runs smooth and quietly...or at least quieter than my seagull. I looked around for a leg extension kit but they're rare as hens teeth. Maybe I'll keep an eye out for a month or so. There's still time before the sailing season starts. here's the funny boat I was hanging it off of.Cute Danica side view (small).jpg



 

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IMG_5333.jpgThat's a longshaft, clutched British Seagull 40 plus. Approx 2-3 hp high thrust. Pushes the boat at about 3.5 knots max.
1979 I believe. 25 to 1 ratio two stroke. Super simple but uses high quality materials. Easy to strip on the dock if needed.
The bracket goes up and down but doesn't have differing degrees of depth unless you adjust the actual wooden mount accordingly for a particular engine.(drill new mounting holes or cut off bits) With a short shaft at the right depth one tends to get cavitation if you go out on the bow. and if the boat isn't full of gear and you encounter the right sort of wave/wake It can roll/pitch enough to submerse the outboard head. that's likely also a result of having a weight hanging off the back(outboard and tank) and an anchor and rode on the bow(box in second picture)
 
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Hey what do you think about this kit
http://www.ebay.com/itm/201487786926
I asked the fellow about it because the leg extension looked exactly the same as the one listed for my engine
here: http://www.marineengine.com/newparts/part_details.php?pnum=OMC0394477

the fellow sent me the mounting footprint dimensions and I would say they are pretty well identical
the problem items to make(for me) would be the leg extension and the drive shaft. The copper pipe and the shift rod could be made and the bolts could be easily acquired
 
Couldn't find the grommet up here, I don't think sierra has it and a local distributer said it was obsolete, but happily they gave the number of a place in Washington that I phoned and who very nicely sold it to me via paypal. whew! Cost $10 US including shipping, which is about $600 Can right now (haha) Have to wait on the rest of the reassembly but i have the head and the exhaust plate on. Will torque the head up properly when I remember to borrow my father's torque wrench
 
It was Auburn Marine actually, still waiting on the grommet and researching longshaft kits
there was one place in New Jersey that had 2 in their inventory but they had been stored outside and supposedly had disappeared after Hurricane Sandy..Word is there is ONE kit in the US now..bahahaha and it probably costs twice what I paid for my motor
I has thinking of building one
I could add an extension to my existing drive shaft (in the middle), and easily build a shift rod and water pipe
i could probably fabricate a leg extension part
However there are some kits for 70s engines on line that look pretty similar, or at least the leg extension looks identical and shares the same measurements(see above) the shaft looks the same except for the impeller attachment (which could be altered easily) I just don't know about the splines top and bottom
 
Well I put the engine back together today and fired it up with 25-1 mix (to make it easy on it)
Ran pretty good (I didn't run it fast ) and pumped water better than it ever has.
Checked the compression when warm about 82 on both cylinders. I think it was getting around 75-78 ish cold)
It might still be missing a little so I might still look at the points as i haven't yet
I like this motor, and I'm familiar with it now, too bad a long shaft kit is impossible to find!
 
You can probably get the complete extension kit from seawaymarine in lynnwood WA just give them a call it will not be cheap thats for sure. You need water tube, driveshaft, housing, shift rod and bolts.
 
I'll try them but I looked before and their catalogue lists them as not having the kit
Auburn Marine searched for me (he said they could search in ways i couldn't) and he said there were only three listed in the states and the list price was $300. If I have to pay $250+ US I might as well make my own
 
Oh and by the way thanks for all the help with the various bits of rebuilding I've been doing. I'm just about to pull the flywheel to check the points, I have to buy a few bolts first for my puller
 
That is aAuburn Marine in Washington state
the fellow there was pretty nice
You're right! hat motor does have just what I want..in fact it is just what i want!
Sadly I'm in Vancouver BC Canada (just north of you) and that seller will not ship internationally nor will he accept questions about anything. (sometimes people that won't ship 'internationally' will still ship to Canada)
 
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