2011 250 pro xs won't get on plane with jackplate down

[tdluxford]

I have a 2011 Ranger z521 with 250 pro xs, it has no hole shot with jackplate all the way down. It has a 10 inch atlas plate on boat, running 25p tempest prop with only one plug in prop, I removed all plugs and prop completely blows out,cannot get on plane at all. If I raise jackplate up to around 11 on my gauge boat takes off better. Once on plane runs fine, it will not go above 1900 rpm with jackplate down, wot is around 5800-5900 once it finally gets on plane, took to ranger dealer and they hooked to diagnostic computer and found no codes, did cylinder drop test and said everything was Ok, they are waiting to lake test boat and get back to me, has anyone experienced anything like this, any ideas on possible repair thanks

[Savage]

I never lower the plate for a holeshot attempt.......Raise, Yes.....lower, never. You should try a four blade prop, if you want a good holeshot.

[EuropeanAM]

Nice speaking with you yesterday.

Please take a moment to review the Forum Announcements, and be sure to provide the REQUIRED info when posting. Thanks!

[tdluxford]

Serial # 1b824131, engine is sitting over 5 inches below pad to prop centerline, going to raise one bolt hole and will advise if hole shot is better

[Savage]

Better raise is 3 bolt holes......5" PTP is about 2" TOO LOW.

[tdluxford]

Raised one bolt hole made world of difference, hole shot is better, engine isn't lagging, thinking of going up one more and seeing what it does, whole problem is related to motor height being too low

[NKY TRITON]

Never owned a Ranger but every other boat I've owned was mounted in the 3rd hole down from the top (I think there's six). 3rd hole with a jackplate should get you enough range to find the sweet spot.

[EuropeanAM]

Since you have an Atlas Plate, you can easily jack that engine up from the console (no need to raise it another hole).

3rd hole should work well... watch RPM, GPS Speed and Water Pressure. Small (1/4" raises on the plate), record each data item.

Continue raising until ONE or more of the following occurs:

-Rpm's INCREASE but speed DECREASES
-Water Pressure Drops below 18 psi
-Unsafe, or Undesirable Handling Characteristics Develop
-RPM's exceed maximum RPM Rating of engine.

Back down 1/8" - 1/4" from your final "test" above, and you should be VERY close to the sweet spot for your setup.