1984 70 hp johnson

I have a problem and would appreciate any suggestions. Spent the week-end at the lake. Motor ran fine for first two days. Last day there I was running wide open and had to slow down . When it was safe to take off again I had no power. Engine runs fine at idle but boggs down upon acceleration. I was able to idle back to the boat ramp. took her back to camp and pulled the plugs which were new. they looked fine. i did a compression check and had good compression. top cylinder was 123 middle was 122 and bottom was 120. I have good spark from all three coils. they are new as well. so is the power pack. I guess it could be junk in the carbs but I had just cleaned them with sea foam. any suggestions will be appreciated.

Re: 1984 70 hp johnson

make sure that all your ground wires on the coils are tight.

Re: 1984 70 hp johnson

I always like to check simple things first which is the fuel filter, fuel lines or oil/fuel separator. If these are restricted the engine may idle, but the engine will die when the system cannot meet demand. They are also something that can be clogged with use if the fuel is contaminated with tank debris, old gas or water.

Once you checked that they are good then go to the more complex items like floats, jets and carburetors. Then the electrical system.

By the way, as fotoboy said, checking loose wires, nuts, bolts and screw is always a good practices at any time.

Welcome johnr2008 and fotoboy to iboats.

Re: 1984 70 hp johnson

how did you clean your carbs with seafoam? this is the only way to clean carbs,
http://forums.iboats.com/showthread.php?t=244013, seafoam will keep a carbs clean, but will not clean it. besure to keep each carbs parts separate, and mark where each carb goes. you also have 3 fixed jets on your carbs, rather than 2, make sure they get back to the right places.

diagrams here: http://shop2.evinrude.com/ext/index.aspx?s1=bf6ad09c53cead335fcfd8a6471c0f7f

Re: 1984 70 hp johnson

I will check all grounds and all other wiring for that matter. I appreciate your replys. I won't be able to do it until saturday.I'll post back and let you know what I find.

to tashasdaddy... by saying I cleaned the carbs with sea foam ...I took them apart and soaked them overnight in sea foam and blew them out with compressed air. That stuff is supposed to dissolve everything that isn't supposed to be there.

Thanks again to all that answered.