more questions about the x22 engine

[supra6909]

thanks for the replies so far guys.  i've got another set of questions for you.  actually, 2 separate things going on. 
1) I've read a couple posts about the rpm's, here's my problem.  the boat starts and idles great, oil pressure running close to 75.  when i press the button to let you rev the engine, the boat will rev to 6K rpms's....so everything is fine.  when i throttle up when in gear, the boat starts out fine and then will not go past about 3500rpms.  just kind of dies out and stays there, even with full throttle.  is that the same symtoms i've read concerning the spark arrestor and/or MAS??? also, it's not even enough power to fully plane off.  no cutting out or anything, it just will not go up.

2)the speedometer immediately shoots to 35 or 40 and stays there, even when the boats isn't moving.  any ideas on that?  all other gauges seems to be working.
thanks guys

[wakejunky]

Our engine tends to misfire under load. not just free revving. I'm gonna bet on spark plugs and while your at it clean your MAF sensor. cheap and easy

[Wet-N-Frugal]

Speedometer:

Try cleaning your Pitot Tubes with a straight needle, and then blow them out with canned air.
You'll find this may help is the short term, but the speedometer will become inconsistent again... due to debris, age, leaks, etc.
Most all the Major Tow Boat Manufacturer's abandoned using Pitot Tubes on their boats a decade ago.

Suffering the same symptoms as you, and out of pure frustration, I designed a GPS upgrade for mine. Here's the post:
http://www.epicmarine.com/forum4/index.php?topic=1841.msg15339#msg15339
And the upgrade does work on '99 vintage boats.

If cleaning doesn't help at all, then typically the problem is NOT the gauge, but the sensors within the Medallion computer (MDC/MMDC). A likely cause is water freezing in the sensors causing them to leak. And you'll want to address this problem before water leaks into the computer and destroys it.

I have a 2000 X22. Has over 800 hours on it... engine runs like a champ.
-WNF-

[sxalberta]

I installed the gps option on my sx and now use the digital speedometer readout

[supra6909]

Thanks for the help with the rpm problem.  i work at a toyota dealership and one of the guys pulled the mas, arrestor and the plugs.  cleaned them all and everything's good now..  i haven't made it to the speedo problem yet.