1989 Johnson 150 - Where to start?

winfieldh

Seaman
Joined
Jun 24, 2004
Messages
72
Hi,

I have purchased the above motor that has not been run in 3 years. It was put away with full tank (70gallons,but did not have fuel stabilizer). I have started draining out the old fuel so I can add fresh, but am wondering the best way to go about bringing engine back online? I am told it did run fine prior to storage. It does look like one cylinder head has been replaced. Picts are here,

http://picasaweb.google.com/lh/photo/7T03JlLlVYEfxnPZAO9ZHjPMFGspHqGFO_myBYDLSys?feat=directlink

Maybe firing it up is the best way to see what's going to break, but I'd like to avoid busting any easily attended areas if possible.

Thanks,
Winfield
 

emdsapmgr

Supreme Mariner
Joined
Dec 9, 2005
Messages
11,551
Re: 1989 Johnson 150 - Where to start?

I'd do a compression check to baseline the powerhead condition prior to starting, and for your future reference. If the compression checks out ok on all 6 cyls, then you can proceed with the next steps to running the engine. You are starting in the right direction, by getting rid of the old fuel. That would include draining the carb bowls prior to starting. Pull all the spark plugs out and spray some light oil in the cyls and rotate the engine with the starter a few rpm to lube the cyl walls. Reinstall the plugs. Changing the lower unit gear oil should also be done. Since the engine has been sitting for 3 years, any residual fuel in the carbs may have dried up, possibly creating a gum deposit in the bottom of the carb bowls. You may be able to start the engine, but if the carbs are gummed up-it may not operate well, so you will be looking at overhauling the carbs. Since you have no repair history on the engine, plan on putting a new impeller in the lower unit. The two thermostats are fairly inexpensive, so replacing them insures that the cooling system should operate properly when first started. Since you don't know the condition of the combination oil/fuel pump, you may want to premix 15 gallons of fresh fuel/oil in the tank. During your consumption of that fuel, monitor the oil level in the separate oil tank to make sure it is being consumed. This double-oiling situation only need be done till you confirm the fuel pump is working normally: consuming oil from the separate tank.
 

fisherman912

Cadet
Joined
Oct 18, 2009
Messages
28
Re: 1989 Johnson 150 - Where to start?

Check out the top secret file at the very top of this forum. There is a very good topic there about "awakening a sleeping outboard"
 

archcycle

Chief Petty Officer
Joined
Sep 21, 2009
Messages
647
Re: 1989 Johnson 150 - Where to start?

Also pull the plug wires and the wires coming from the powerpacks into the coils and inspect the contacts for corrosion. If it's been there for years there's no telling whether they're still greased up in there and preventing humidity from entering and fouling them all up.
 

winfieldh

Seaman
Joined
Jun 24, 2004
Messages
72
Re: 1989 Johnson 150 - Where to start?

Thank you all for the responses. This is just what I was looking for.
 
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