1976 40hp merc on this boat pic

[domains]

hi jas....Winter in canada soon, can't play with prop size or pitch. I just bought this motor 40hp thunderbolt that runs very well. ran boat 2 years with 20hp johnson with 34kph on a stock new prop (alone in boat). Anyone try this setup 13foot with old 40hp horse power at flywheel.

Pitch 15 or less? 15 pitch what diameter or 14 pitch what diameter. Can spend some money throw me a few sizes tryed.

heres a pick of same boat i got. 13 foot boat

http://i156.photobucket.com/albums/t4/domains/Picture016.jpg

 

[Texasmark]

Re: 1976 40hp merc on this boat pic

Several people on here can probably help. Will give it a bump for you.

Mark

 

[steelespike]

Re: 1976 40hp merc on this boat pic

Cool looking boat.What is max rated hp? What is the present prop?
you can measure diameter by measuring center to end and double.
Difficult to even be sure where to start without some present figures.
You should fine tune the setup raise the motor 1/4 in. at a time until just before ventilation becomes a problem.Just add 1/4 in sticks on top of transom but maintain a good grip with clamp.Be sure it continues pumping water.Give us present rpm, speed and hole shot. Then start making decisions on a prop.

 

[domains]

Re: 1976 40hp merc on this boat pic

Hi...Prop is 10X13 max for boat is 50hp. I have no gage, that would be my best setup i guess.Is it easy to install specs say 5200 RPM max. hope its not yellow wires from stator (have none)

 

[steelespike]

Re: 1976 40hp merc on this boat pic

Check on the net for a Tiny Tach.I think there is one that can be used for a number of applications.Also if you get one for a 2 cylinder I believe it will work for any 2 cylinder.I think they are reasonable and easy to install.
Use the 10X13 prop for now, when you get your tach.A GPS is best for accurate speed.Just guessing the 13 might be pretty close.

 

[domains]

Re: 1976 40hp merc on this boat pic

Found what i need, plugs to sparkplug wires so i'm set .I thought i needed yellow charging wires under stator( don't have) thx for help.



http://cgi.ebay.com/ebaymotors/SenD...009QQitemZ190174149617QQrdZ1QQsspagenameZWDVW

 

[steelespike]

Re: 1976 40hp merc on this boat pic

Found what i need, plugs to sparkplug wires so i'm set .I thought i needed yellow charging wires under stator( don't have) thx for help.



http://cgi.ebay.com/ebaymotors/SenD...009QQitemZ190174149617QQrdZ1QQsspagenameZWDVW

Did you specify for a 2 stroke?Does it matter?
Let us know how it works as I'm thinking of the same but appropriate for my 4 cyl. Merc 500.

 

[domains]

Re: 1976 40hp merc on this boat pic

TT226R-1c seems to be the right one for my system, TT226NR-2C seems to fit all 180 degrees.