70 hp Johnson reduced power

[Vertigo]

I have a 1985 70 hp Johnson that idles nice, but when you apply the throttle, it bogs a bit, then, as it revs up, it takes off. We have had it serviced but still have limited power off the line. The carb and injectors have been addressed. Any ideas as to what it maybe? It runs fine once we get going. It also slows when taking sharp corners, for instance when tubing.

 

[Dhadley]

Re: 70 hp Johnson reduced power

Let's start with a model number. You mentioned carbs and injectors but you won't have both. If it is indeed a 1985 then it's a carb model. We'll assume it is a carb'd model and if the carbs are clean then some rejetting might be in order. Some info about your set up might help too. Are the top rpms where they need to be?

 

[Vertigo]

Re: 70 hp Johnson reduced power

You are correct, it is a carb model as it is indeed an 1985. The boat is at our cottage, so it is difficult to say what the RPM's are. I do however know that it idles at 1000 and I believe it is in the 5000 range at the top end.