Have Boat Questions? Ask a Boat Repair Expert.
Couple of things.
Make sure the control cables or linkage is not sticking.
Check the throttle shutters in the carbs are closing all the way.
On the side of the carbs is a flat link arm. They are adjusted by a small screw and flat nut. Loosen the screw. Move the control to neutral/idle. Move the carb linkage to allow the carbs to snap shut, they are spring loaded. Check the throttle plates are closed. Snug the adjusting screw so both close at the same time all the way.
the carbs are now synced.
On the towershaft, the rod that controls the throttle just to the side and rear of the carbs is a curved throttle cam. At idle the grooved line should be next to the roller on the carb linkage but not opening the linkage. Adjust as necessary.
At the top of the towershaft is the connector to the timer base. make sure this isn't binding.
Try these things and post back what you find.
Don't worry about the primer bulb not getting hard.
The rpm is controlled by two things the timing and the fuel ratio to air.
Things that will cause higher rpm are, advanced timing, air leak, lean idle mixture, carbs partially open.
Have you checked the timing on the engine?
I'll bet the timing is too high at idle.
Look at the bottom of the towershaft the adjustment screw is there. Time it in the water with a timing light. There should be a decal with the specs on the engine.
You are referring to the recirculation hoses. If one breaks then you are getting extra air into the engine.
Do you have a good idle now?
You should be OK then. Once you put the boat in the water set the idle speed so it stays running in gear but as low as possible. Probably about 900 to 1000 in neutral. Set the idle mixture as lean as possible without any back fires or popping where it still can accelerate and get on plane.
Forget the dry block nut case!
When you installed the lower unit where you sure to get the water tube in the midsection indexed properly?
You can put a garden hose on the water tube and turn the water on and see if there is a blockage. Check the fitting where the indicator tube connects for blockage.
There is a tube in the midsection that goes into the output tube of the water pump. If they are not connected then no water to the block.
The impeller key? Goes on the driveshaft and the impeller slides over it. Without it the impeller won't turn.
Let me know how you make out and don't forget to rate! Thanks
Did you require a phone call?