2006 DF140 RPM problems

[nlredo]

Last year B4 winter the motor would not rev past 4000 rpms. This spring I changed all the fuel filters, High pressure included, new plugs, water pump rebuild, changed oil then took it out and ran with fresh gas and it would not rev past 4800 rpms and only if I slowly increased the motor speed, if I punched it it would not go past 4000 rpm.
I took it back home and removed the VST and cleaned it out, put boat back in the water and now it revs to 5000 rpm but wont go past 5K.
I also checked to make sure the butterfly on the throttle body opens all the way when i advance the throttle. The motor runs great (no misses) at all rpms it just wont get past 5k. I have run it on a small tank with fresh gas also.

Can anyone think of anything I might have missed ??

Thanks in advance for your help

[H2OTech]

We don't know what your fuel pressure readings are out of the vst.
We don't know what the compression readings on the motor are.
We need to know that you're getting good spark on all cylinders.
I'll look up the fuel pressure requirements if you can get me the model number.

[nlredo]

I have the repair manual. Ill check the spark, compression and ill have to rig something up to check the pressure out of the VST.

[nlredo]

The fuel pressure is 40 psi. getting a nice fat spark on each cylinder and the compression on each cylinder is 230 - 235 psi. took the boat out today and ran it with my 3 gal. tank with a whole bottle of sea foam in it and it picked up 400-500 rpm after i ran that through. my next step is to send my injectors out to be cleaned. ?? any other ideas ?

[nlredo]

I sent the Injectors out to be cleaned and all is well now.