Won’t plane outt

Jkelly4

Recruit
Joined
Sep 9, 2019
Messages
1
I have a 1983 procraft 1540v and a 1974 70hp Johnson with a 13x19 pitch prop, cavitation plate within 2 inches from the bottom of the hull and it won’t come out of the hole any ideas?
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,544
How about some history including did the boat ever see 30+ mph with that 19P prop? Running light with one person or loaded with folks? Got a tachometer? Run a compression check? Numbers above 120 spinning the starter with all the plugs out and throttle wide open position? On the plate location, which way is it within 2 inches of the hull bottom, up or down from it? How hard is it to get started? How often is it operated? In what condition is the fuel? When is the last time the carbs were looked at? Plugs? What kind of trim position are you running? Not familiar with the boat....where is the weight distributed? What's the history on the boat? Sit out in the yard and fill with water very often?

Back in the early 1970's the 60's on 15' light FG tri-hulls were running 15P if you wanted to ski one person with 2 in the boat on 2 skis and 17 if joy riding with 2-3 folks. 30 was about tops for them.
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
12,944
I think a 19 is a little too much prop for that boat, but if the engine is up to snuff, it should get up on plane.

You say the Anti Ventilation Plate is within 2 inches of the Bottom of the hull. Is that, as asked above, 2 inches above or below the hull bottom, or 2 inches away from it when the engine is tilted down all the way?

As mentioned above
Compression Test
Does the Spark jump a 7/16" gap?
Fuel getting to all three carbs?
Are the carbs functioning?
That engine has a WOT range of 4500 - 5500 rpm
 
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