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1992 Johnson 40hp, no power unless using priming bulb

Oxide80

New member
Looking for a little help with diagnostics on a 1992 Johnson 40hp on my 17' Tracker Deep V. Boat sat in a barn for 6 years, purchased it and got it home. I knew the fuel was old so I drained it, replaced the water separator and inline fuel filter. Replaced spark plugs also. Fired right up and idled with the water muffs on, water flowing from the outlet. Checked oil level that was 3/4 full.

Initial shake down in the water fired right up and idled. Backed out no issues, chugged around for a few minutes letting it warm up. Throttled up with only a slight change in rpm. I use the primer bulb abd it takes right off and will rev up. Some times it stays running at high rpm others it cuts back down. One time it cut back on RPM I had an alarm sounding so I shut down and restarted. No further issues with an alarm after that.

Im going to change out filters again, who know if it sucked something up but I couldn't see any debris in the tank when I drained it. Also get some carb rebuild kits. My main question is could the VRO cause these symptoms? I've done plenty of work on 2 stroke snowmobiles and dirt bikes, but never anything oil injected.
 
If a motor like that sat for 6 years you would be wise to run at 50:1 mix in your tank until you confirm operation of VRO unit.---Perhaps too late now.-----Install a new water pump impeller.----If motor sat with fuel in carburetors for 6 years the carburetor high speed jet could be plugged !----Post the compression test values.
 
If a motor like that sat for 6 years you would be wise to run at 50:1 mix in your tank until you confirm operation of VRO unit.---Perhaps too late now.-----Install a new water pump impeller.----If motor sat with fuel in carburetors for 6 years the carburetor high speed jet could be plugged !----Post the compression test values.

Thanks for the quick reply. Water pump is on my hit list and I was watching it closely. Boat only ran maybe 5 min and went a mile at best before I parked it. Yea a possibility of damage from lack of oil that was a chance i knew I was taking. I will do a compression test and add some oil to the fuel. Thanks for your help!
 
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