omc 140 looper w/v6 gearcase. overpropped?

[3car]

long story short, I bought a 2000 17 ' javelin venom with no motor, and I bought an 86 ' evinrude 140
looper that had been assembled from a few different motors. it has a v6 gearcase . the boat is slightly
overpowered , and has a 22 p raker prop . the problem is , the boat wont get on plane , just digs . once it
finally planes out , it only reaches about 51 mph by GPS . tach is not working , so I don' t know rpms.
I read somewhere that the looper v4 engines that got the v6 gearcase actually had lower gearsets in
them. is this true? if so , I may be over propped . from my research, this model boat with 115 's typically
run a 22 p prop to the high 50 ' s, but that is with the smaller lower unit and prop .
I was thinking something was wrong with the motor, but now I' m not sure .

someone also mentioned That I may have too much motor in the water, could that cause the planing problem? I have a manual Jack plate that I am going to install, but I was trying to work a few bugs out first.

 

[kenmyfam]

Re: omc 140 looper w/v6 gearcase. overpropped?

Set up is huge. Loading of gear, motor height, trim to name but a few. Post the model number so everyone can see just what it is. (shaft length etc) How many splines are on the prop shaft ?? V6 lower end has 15 and the V4 has 13.
When you say "dig's in" do you mean bow in the air or bow digging in ???

 

[steelespike]

Re: omc 140 looper w/v6 gearcase. overpropped?

the 140 is 2.00:1 the V6 1.86:1 Untill you get your tach working there is no way to make an accurate prop selection or to tell if the prop has put the motor in the correct rpm range.The Raker prop may be slower to plane and the higher gears would add to that.
Your antivent plate should be visable at speed.usually about an inch above the bottom this could be more with a jack plate.Be sure the throttle plates are opening all the way.

 

[Dhadley]

Re: omc 140 looper w/v6 gearcase. overpropped?

And there is a V4 gearcase that is the same size as a V6 with yet another ratio, a 2.15:1 (if I remember right). So, if you do have a 4 3/4" gearcase with a 15 spline shaft you could have a great range of ratios.

 

[3car]

Re: omc 140 looper w/v6 gearcase. overpropped?

And there is a V4 gearcase that is the same size as a V6 with yet another ratio, a 2.15:1 (if I remember right). So, if you do have a 4 3/4" gearcase with a 15 spline shaft you could have a great range of ratios.

Mine is 4 3/4 with 15 spline. If i mark a refrence point in the flywheel and block, then another on the hub and gearcase, I should be able to rotate the flywheel one revolution and count prop rotations correct?

 

[steelespike]

Re: omc 140 looper w/v6 gearcase. overpropped?

Correct,with the plugs out.

 

[3car]

Re: omc 140 looper w/v6 gearcase. overpropped?

appears to be about 2.5:1, so back to square 1.