1986 Evinrude 150hp Couple of Questions bout motor and lower unit PLEASE!!

[86invader]

(1) Hello there. I just replaced my lower unit with another lower unit (Old one came apart from inside) The one i got is a "Commercial 150hp" lower unit. First off will it hurt my boat if i have a regular engine with a "Commercial" lower unit on it? I just bought the boat and the guy i bought it from gave me the commercial unit (He has Millions of boat parts every where)!

(2) I found this rubber tube/Hose that comes down behind the motor and is just hanging. (Not hooked up to anything). Where does it connect to? I have looked every where! I know its to my speedo cause it dont work. Can someone give me a pic of where it goes or a diagram? thanks

(3) Should i use Copper core only ignition wires on my unit? i want to tune it up before i take it out this winter to fish. I have these special champion "no resistor" spark plugs in it now (kinda wiern ive never seen these) lol

(4) when i run the engine with the ears with the water on i have water coming out between the upper and lower section of the motor. Is this ok? (Where the lower unit bolts to the upper: In between the two) the guy i bought it from says that its normal cause the water coming from the hose is pressurized. I feel that hes blowing smoke up my but i just wanted to make sure i dont break anything else.

(5) I have a 15x7 prop on it now what can i do to get a little more speed? (No big deal) now its around 45mph. my boat is an 1986 invader ski and fish 18.3 long.

Sorry for all the dumb questions but if i dont ask i will never know. Thanks dave

 

[emdsapmgr]

Re: 1986 Evinrude 150hp Couple of Questions bout motor and lower unit PLEASE!!

It won't hurt your engine to use the commercial lower unit on your engine. The problem is the gear ratio in the commercial units is not the same as in the normal consumer lower units. The gear ratio in your original unit is 14:26. The gear ratio in a commercial is 15:28. The commercial is geared for power and will not run your boat at the same speed as with your current prop. The rubber speedo hose connects to a small plastic hose barb at the front top of the gearcase. Look at a 1983 150 gearcase at this website: epc.brp.com. It is item 1A on the gearcase drawing. I'd get factory spark plug wires from a Bombardier dealer. They come as a kit (one per spark plug) with all the parts: part number 582365. If you have a strong telltale and water exiting the exhaust relief ports in the upper midsection, you should be just fine. There is no seal/gasket between those two parts. If you change the lower unit to the commercial lower, you will have to experiment with props. Likely it will run somewhat slower than the stock lower unit due to prop inefficiencies of the different prop pitch you will have to run.