85 hp seems to have lack of power

tsoileau

Cadet
Joined
Apr 12, 2006
Messages
16
I have a 77 johnson 85 hp V4.(also have a 9.9 that I am working on). I have not really run the engine for about 4 years. I have cleaned the carbs, changed the gaskets between the carbs and the manifold, changed the fuel pump (got a used pump from a dealer--he said it came off of a 88 year 94 or 95. Went and ran it today. Idles great. Seems to run real good also except that I remember the boat getting out of the water a lot quicker than it does now which seems that the power that was there is not there now. After it planes out--good speed--just not quite what I remember. RPM's are around 4000-4400. Sort of remember them being around 5000+. Engine runs smooth at max throttle--which makes me believe that everything is as it should be--but the gut tells me no. Am I just nuts or should I check something. Ran the boat for about an hour to an hour and a half-ran ok. Put 7 fresh gal. of gas with about 1.5 older gas. Put gas stablizer and cleaner in with the 7 gal. I appreciate your advise and help.
 

LubeDude

Admiral
Joined
Oct 8, 2003
Messages
6,945
Re: 85 hp seems to have lack of power

Are you sure that the engine has the same prop on it as the last time you ran it? Even 5,000 isnt high enough, you should be 5,500+. I used to run mine at 6,000 all day long.
 

tsoileau

Cadet
Joined
Apr 12, 2006
Messages
16
Re: 85 hp seems to have lack of power

Did not change the prop or change the setting on the jack plate.
 

TD_Maker

Chief Petty Officer
Joined
Aug 31, 2005
Messages
564
Re: 85 hp seems to have lack of power

Sounds to me like you may have dropped a cylinder or two. Sometimes on the V-4 OMC engines, the cowling will hook some wiring on the way down and pull them off or loose. Check for any loose wires around the coils and power packs. Also, pull the plugs and look for really wet plugs which will point you to a cylinder that may not be firing.
 

ondarvr

Supreme Mariner
Joined
Apr 6, 2005
Messages
11,527
Re: 85 hp seems to have lack of power

If the boat sat outside for all those years, it may be full of water. Nothing like 500lbs of soaked foam to slow it down.
 
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