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Is my lower unit causing my bogging issues?

B

bigtime_mcalpine

Regular Contributor
so here what I’m up against:
1987 20hp Evinrude. Carb thoroughly cleaned 2x in bath of varsol over 48hrs, new carb kit put in, plugs, sub’d in another coil and tried in cyl 1 and cyl 2, new fuel lines, replacement fuel pump, replacement CDI, new lower crank seal, new intake and reed gaskets and reeds thoroughly inspected.

Starts on first pull. Idles smoothly. Will putter along at trolling speed but give it any kind of gas and it just falls flat on its face and will just stall.

I replaced a few thing (above) hoping that would address but nothing! So took it on water today after replacing CDI and no change. Started and puttered around perfectly, gave it gas and it momentarily half reacted then died. Ran it in reverse…same. Buuuuut, I then tried in neutral and that thing just rev’d smoothly to top RPMs….im starting to wonder if maybe I’m dealing with a lower unit issue…of course I just sold my extra 2 weeks ago. Do you guys think this could be cause?
 
My son had a motor that actually did have a lower unit on the verge of locking up and he tried everything in the world to get the motor running right. We were discussing any other possible solution while having a beer and leaning on the back of his boat. I reched up with my foot and went to spin the prop and it barely moved. I asked if he had it in gear and he said it was in neutral. We both attempted to spin the prop and it barely moved. We opended the drain plug and very thick brownish crap came out in clumps. Apparently he had leaking seals in the foot that had been allowing water to enter for a very long period of time. So, put your motor in neutral and tap it with our foot and see if it spins freely.
When cleaning the carbs, did you clean the main jet? If you remove the drain plugs from the bottom of the bowls, the main jet is inside that hole. Screw those out and I bet you'll find crap partially clogging them. Because they're in the bottom of the bowl, if the motor has been sitting for any length of time, the gas will evaporate and any sediment and trash can clog those jets.
 
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