2006 ranger 188vs 150vmax 8" t-h marine z-lock jackplate setup help

[BASSFAN07]

Guys,
i just put a z-lock 8" manual jackplate on my 2006 188vs with 150 vmax with 23-m 3 blade prop. Main reason was I'm putting a talon on my boat and I wanted to attach it to a jackplate. Before today my vmax was just bolted up low on transom and performed pretty well.

With my boat leveled and motor leveled, my pad is 16 4/8" from ground with the center of my prop shaft at 12 1/8". That's 4 3/8" prop to pad correct? It appears the motor is significantly higher than when originally mounted. Am I supposed to raise it even more? it seems way high and when I ran it at the lake for a few minutes earlier after installing the plate the performance sucked with blowout and it didn't want to run more than about 5000 Rpms. Previously it was running around 5800 or so at 56mph mounted on transom.

Please help an ignorant ranger brother.

[mdtritn21]

Are you sure you measured it correctly? Use this to measure it. http://www.bbcboards.net/showthread.php?t=62660

[BASSFAN07]

Yes. I used that diagram

[mdtritn21]

Raise it up to 3 1/2" under and see what it does. Putting the plate on shouldn't effect the rpm's unless it too low.

[BASSFAN07]

Thanks I'll make the change and see what I get.

[BASSFAN07]

Hey guys raised my prop to pad to 3-3/4". That was the max at the current holes I have the motor bolted to the JP. I ran it today. My water pressure is 15 on my gauge trimmed down and on plane. Boat hops out of the hole and gets on plane beteeen 3-4000 rpms. I was able to trim up the motor and at approximately 5600 rpms I was running 56.5 in relatively rough water. My water pressure was dropping to 10. Does that sound too low? There is definitely some prop slip occurring.

[merczilla]

Did you by chance level everything and get a dimension from the center of prop shaft to the bottom of the pad just to use as a reference point?

[BASSFAN07]

I measured it as shown in the diagram linked above. Leveled pad measured to concrete. Leveled motor and measured to center of prop shaft.

[mdtritn21]

When was the last time you put a water pump kit in your motor? The Yamaha's will run WOT with 11 lbs of water pressure so it may be alright or it could be a worn out impeller. Make sure that the concrete pad you measured to is level also it will make a difference. I don't think 56.5 with the 23m and the added weight of the Talon is bad and the prop doesn't show much slip.