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77 85h seahorse

G

Grown in Tx.

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Last time i had it out it wouldn't start after a drift over a flat.
I found the carb jets were clogged wuth gunk. I have gotten it to start and idle for a few minutes in the driveway but still isn't right. Assuming all cylinders have good pressure, and without tearing into the motor, what should i start replacing to make sure my family and myself can be confident without worry of being stranded again. I plan on replacing plugs, wires, both carbs and all spark packs but what else? I can't afford a new motor and this one ran strong. thanks in advace
 
For its age it definitely needs new powerhead gaskets or at least head gaskets. Make sure gear case has no water and cooling system is sufficient!
 
Grown in Tx. said:
Last time i had it out it wouldn't start after a drift over a flat.
I found the carb jets were clogged wuth gunk. I have gotten it to start and idle for a few minutes in the driveway but still isn't right. Assuming all cylinders have good pressure, and without tearing into the motor, what should i start replacing to make sure my family and myself can be confident without worry of being stranded again. I plan on replacing plugs, wires, both carbs and all spark packs but what else? I can't afford a new motor and this one ran strong. thanks in advace
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Seems pretty drastic for a dirty carburetors problem. Better put your efforts into cleaning the entire fuel system.

For reliability, if you haven't changed the water pump impeller in a long time, now is the time.
 
It is extreme, but not as extreme as paddling a 17 foot boat a couple miles as people fly by with blinders on.
Like i said it ran strong, never had issues other than the "johnson cough" while idling. I'll do a comp check today.
 
When you refer to the johnson cough the motor is telling you something is wrong. Any cough at idle speed is fuel related normally and must be addressed. Too rich and you will carbon up the cylinders and heads, and too lean you will damage the cylinders and rings with lack of oil.
 
I felt like crap today and didn't get out, what i do is make a list of parts and prices from wholesale marine. I didn't see the new carbs so I'll probly just rebuild mine.
I will be buying parts in this order, i cant get the entire list at once so it will be done in stages
(1) $550 will replace the
coils, power pack, batt cables, carb rebuild kits, fuel lines, clamps, filter, bulb, starter, solenoid and rectifier.

(2) $330 will replace my tilt/trim motor&res.

(3) $550 will replace the stator and timer base, i dont think i need those right now.

Also priced a wiring harness $130 and a throttle cable for $89
There were prices for the power head parts as well as lower unit parts but I'm not ready for all that yet. It seems for about 2000 ican rebuild the whole thing inside and out. That's a lot cheaper than a new motor or a newer used motor I'll probly have to troubleshoot and work on.
 
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??--------------You are planning on replacing parts without any testing ??-------------Some of these parts are very well made and last a long time !!!
 
I appreciate it, i was going to buy a comp guage yesterday when a buddy told me he would give me one today so, I'll have results posted in about 11 hours. I know some parts are still good but i want to do everything possible to not break down again. 2 of the 4 coils have a cracked housing, they are still woking but for how long. The power pack looks fine on the outside but....i have no idea how old it is. I have an old waterproof container to put certain tools and spare parts in, just in case they will be needed while out on the water. I do not ever want to be stranded again and can't afford a new motor.
 
So do you replace light bulbs around the house before they pop ?-----------Just kidding here.----------Electronics can last for minutes or for decades.----------Nothing wears out inside a " powerpack "
 
My battery was low so i couldnt get a propper reading, the 1st was #80, 2nd was just under #80 then the 3rd and 4th both were lower like 70 and 60. But the batt was real weak and dragging by that point and the first 2 were reading low when i re-checked them. 1 more day.
 
Thats a little low it could be carbon on the rings. As long as they are even it should run good enough to do a good decarb. While ideling do a cylinder drop test. Pull a plug wire and quickly put it back on it should respond the same on all four cylinders. A good pair of channellocks will keep you from getting bit. If it is firing on all four cylinders by all means start working on your list. Fuel first rebuild the fuel pump and carbs and replace the fuel lines. New plugs for sure wires may be alright but wouldnt hurt to replace. Water pump impeller and change the gearoil and replace the drain/fill plug washers. Check adjust engine sync and get a can of seafoam spray and on the water give it a good decarb. Bring the engine up to normal temp and at high idle spray the seafoam in the carbs evenly until it starts smoking real good and quickly shut it down. Wait half an hour and start it and run it WOT for 15 minutes to blow the cobwebs out.
 
Thanks, I'll start the process you described for me kim, the manuel said to look for a min of 100psi (as johnson does not publish a recomended psi for this procedure) and i was hoping for no more than 5psi difference. Like i said its a strong motor, i HAD all the faith in the world in it, but is a 1977.
 
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