I have a GD LT 20 , it seems to bog down easily when I lower it into the water. I dont think it is turning fast enough at full throttle. I am going to install a mini tach this weekend. What should the redline be on this Vanguard 20?

4000-4200


But regardless of what your wide open throttle readings are, that has nothing to do with it bogging at idle. Probably just have to raise you idle 100-200 rpms.

It is bogging at full throttle when the lower unit is dropped into the water. the boats performance or speed is the same at full and half throttle. Would the RPM increase correct this? My prop is also extremely worn ...

I know that you dont have a tach, but how bad is it bogging? you loosing 50% of your rpms? more/less?

probably close to 50% , i had the carb rebuilt and the head gaskets replaced in December no improvement.

Well then it sounds like you still have a problem (or should I say that your problme wasnt corrected properly when it was worked on).

Now, back to your original question, yes the motor will lose some rpms when you drop it in the water, but if you are losing 1/2 the power that the engine is developing that doesnt sound like your governor is just out of adjustment.

i have never driven the boat when it is not loaded. 3 guys , dog and gear. Running maybe 10-12 MPH. The Hull is a 14 ft lowe line. It just wont "rev" up when you hit the throttle when the prop is in the water. if the prop is out of the water it will "rev" up to full throttle. Could this be the govenor?