9.9 johnson rebuilt

jay mendoza

Petty Officer 3rd Class
Joined
Aug 14, 2009
Messages
81
Well we finally got the whole engine back together and ran it on the lake for Labor Day without a hitch, thank goodness. It took three weekends of going up to our cabins by the lake to complete this project which has been hanging over my head for a couple decades. I knew the 1975 9.9 had been seized and had issues back in 1980 when I bought it used, and had purchased everything needed to rebuild it, including .030? over pistons, seals, bearings and gasket set, but I never found the time. Additionally, it just kept running year after year, so why mess with it? A recent find of a pristine ?Rude 9.9 power head from Rancho Marine about a year ago renewed my interests as it would preclude a complete power head overhaul and make things much easier. The original paint was also still available so that put it on the schedule for the 2009 season.

We also found that the gear case was full of emulsified oil and needed re-sealing, thank goodness Holloway?s had all the seals. The one thing I forgot however was the upper water tube grommet, and a fuel pump diaphragm kit, which meant that we had to wait another week for these parts. This was a blessing, as when we returned, all the fresh oil had wept out of the gear case as I failed to torque the drain plug adequately. So we refilled it and used a lot more torque, ?nuff said!

Next ,on went the new power head after a fresh coat of Johnson gold paint, retimed the ignition, synced the magneto and throttle cam, set-up all the linkage adjustments, lubed everything, and the lower unit with new seals and water pump was bolted on next. The only error was the coil primary wires were swapped, resulting a in a backfire, this was quickly remedied and she fired on the next pull. The engine ran super smooth and required just a minimal idle speed and mixture adjustment before heading out to the lake.

Even with three of us in the 12 foot Western W-12, we could outrun the dock hands at Holloway?s in the same boats with 9.9 hp engines, I love that 15 carb John talked me into back in 1982, it makes a real sleeper out of the 9.9. Looks like I?ll be back to just changing impellers, gear oil, and the occasional pull rope and recoil spring for the next 25 years. We did notice it now gets better gas mileage, with a small increase in power over the old engine.
 

ChrisAG

Petty Officer 2nd Class
Joined
Sep 13, 2009
Messages
176
Re: 9.9 johnson rebuilt

Nice work - but why go to all that trouble, why not just get a "newer" used engine? Then again, I understand the value of doing it yourself...
 

Rick.

Captain
Joined
Jul 30, 2006
Messages
3,740
Re: 9.9 johnson rebuilt

Congratulations on a job obviously well done. They are great engines. Rick.
 

jay mendoza

Petty Officer 3rd Class
Joined
Aug 14, 2009
Messages
81
Re: 9.9 johnson rebuilt

You are right Chris, and I did consider buying anouther complete replacement but this engine has no corrosion problems, and it's the early points version (1974-76 had points) which I like as I'll never have a power pack going bad and ruining a fishing trip. The other reason for not purchasing another engine is cost: My total costs for this rebuild were under $300.00, as the spare power head only cost me $125.00, and I spent $80.00 on the lower unit, and another $70.00 on misc seals, gaskets, pump kit, and new plugs along with a bottle of gear oil.

The other reasons are I know this engine and therefore what I'm dealing with, another engine could open up a whole new can of worms, at least this engine was running when I took it down for a major servicing. Add to that the fact that the Johnson "gold" color(actually a metallic gold/green) does not show staining like the white and grey models, and is classy.

Now I have a spare power head, and all the internal parts to rebuild it, that I can overhaul whenever time allows. I might try a bit of blueprinting of the ports to make them all open at the same time on both cylinders, and open up the apertures of the leaf plate for a bit more flow, "D" the exhaust ports, and use hand cut fibre reeds, just for a little more suds, and set it aside as a spare.
 
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