Got my boat out for the first time yesterday, have some ?'s

[TIGGER]

I finally got my boat out in the water yesterday for the first time. I bought it last fall with a sick engine. Water was mixing in with the oil. I have spent all my free time this past month working in this thing. trying to get it ready for the 4th. The problem was a bad intake gasket. I would like to thank all of you for answering my questions.
I have a few more questions. My speedo did not work yesterday. Can someone explain how the system works? What are the common problems? How do I fix it?
The forward reverse cable was siezed when I bought the boat. Some WD40 and some care got it free but I am not sure if it is out of adjustment now. Revers is all the way back. Forward is straight up and all the way forward went in reverse again. Is that correct? How do I adjust the shifter?

[Aluminum Squirt]

Never trust a boat speedo or a boat gas gauge. Boat speedo's use a little water pickup near the bottom of the treansom, I think its called a pitot ? tube, and it feeds water up through a small tube to your speedo where it magically changes a pressure reading into a speed. Its not very accurate and prone to leaks. I would buy an inexpensive GPS (around $100 and up), mount it somewhere and get rid of the speedo. Then you will get an accurate reading, sometimes a little too accurate for people who think their boats are fast, and you won't have a pressurized water tube coming into your boat (that's never made much sense to me, the goal is to keep the water out). GPS is nice for tuning and you can save waypoints for your favorite beaches, fishing holes, or least favorite shallow spots. I have no clue how to adjust a reverse cable, I have no reverse. Good luck-Aluminum Squiurt

[steelcomp]

Speedos are like anything else. There are good ones and bad. I know mine is accurate within a mph, up to between 90 and 100, verifyed at Ming on the 1/4 mi. If you run on the river, a GPS isn't going to give you accurate water speed, only ground speed, which won't account for current.
Al. Squirt is correct in saying the speedo is run off a "tube" which hangs down slightly below the water line in the back of the boat, and it is called a pitot. (pee'-tow) It senses water pressure from the forward motion which, through a long small hose, pressurizes a coiled tube in the speedo. As the pressure increases, the coiled tube trys to expand, and this movement is translated into the movement of the needle, which is calibrated and read in whatever speed incraments...mph, kph, etc. If yours isn't working, it could be that the pitot is plugged with crap (happens frequently enough) or the speedo itself needs repair. Disconnect the line at the speedo and blow air through the line backwards. Don't blow pressurised air into the pitot...you could damage the speedo.

[TIGGER]

Thanks guys, I will check the line for blockage. - Tigger

[Aluminum Squirt]

Steelcomp is right about the current, didn't even think about that. That's all I run on so I forget about it, I just always make a run in each direction for tuning purposes to get a good baseline number. Anyway, yes speedo's can be accurate, most aren't. GPS is very accurate for sustained speed, not so good for acceleration. Anything is better than nothing, as long as its consistent, that way you can tell if any of your changes are making a difference in MPH.....which is what most of us around here are looking for-Aluminum Squirt

[Ken F]

Hey AlumSqt-
Hows the boat running? Major improvements?
Ken F

[SmokinLowriderSS]

Normally on a reverse gate, the handle foreward is foreward, straight up puts the bucket roughly half-way down over the nozzle, and all the way back is reverse (the bucket fully covers the nozzle).
I'm having a really hard time imagining a linkage that gives you reverse at both ends and fwd in the middle (not to mention WHY anyone would have such a set up). That setup would be confusing as heck to me.

[TIGGER]

Thanks Smokin... I am not sure what the problem was with my shifter. The only way the boat would go forward would be with the shiter in the middle- 3/4. All the way forward kept it going back? As I said this was the first time. I will try all the way forward again and see what happens.

[LVjetboy]

I'd suggest checking your gate position as you move the shifter when your jet's out of the water.
As for speedo, Steelcomp's post is right on. Many say a pitot speedo is bogus, but my experience with Magellan and VDO is both were within 1-2 mph of GPS from plane to over 80 mph. In the case of VDO, the needle hovered at 100 mph when the GPS clicked 100 mph. Not bad. Yes, the pickup can get blocked and read low. Or you can have a tube leak and read low. Other than that, if calibrated correctly, the pitot reads just as well as GPS, and a bit easier to see at speed.
jer

[SmokinLowriderSS]

The same technology that a boat speedo uses has been used for well over 50 years in aircraft for everything from altitude sensing to airspeed indication (I build LearJets). We DO go to very great lengths to insure that the system tubes are absolutely sealed but barometric pressure sensing for speed is not inherently in-accurate as long as the gauge is properly calibrated to the probe and the tubing is ALL perfectly sealed at all connections. Yes, in today's computer-driven, electronic wonder-box avionics systems, baro. pressure info is STILL fed to the computers so they know what the aircraft is doing. Most aircraft I have ever worked on have at least 2 (often more) pitot probes and 4 or more ambient pressure ports.

[Aluminum Squirt]

KenF, Not so good. I smoked my motor at last years world's and haven't done much to it. Haven't even torn it down yet. The new kid, new house project, and work have kept me from doing much else. Saving every penny right now so I can hopefully squeeze a rebuild in this winter while the wife isn't looking. Set up is good, I'll be looking for 80 with a stock ZZ4, not to bad for the horsepower-Aluminum Squirt

[Rampager]

That sounds like a huge drag Squirt. I know how the $ flow thing goes tho. I'm dying trying to finish this thing!
Have you seen the "beast from the east" Ken??? The headers work sweet and the way the ended up dumping under the static waterline worked out great, real stealthy for the cops ;)
Whats new in your neck of the woods? I still expect you to tell me how bad the bank raped ya to cash that MO, I owe ya still! Been ultra busy as I am sure you could have guessed. Thrilled with the hull tho
Check out the most recent pics at...
http://www.eagleracing.ca/Forum/viewtopic.php?t=4117
Sry for the thread hijack tigger, sounds like your reverse bucket cable is travelling over center somehow and the bucket is flipping over center and closing again. Look at the action of it while someone else moves the shifter and hopefully what I just said makes sense. Make sure thats working perfect before you boat as its a very key safety feature of the jet. Emergency stops are possible if you need to. You'll find the jet handles like a dream once you learn it. Shifting from forward to reverse can be almost instantaneous
Cheers

[SmokinLowriderSS]

Definitely. Sitting still and maneuvering, you don't think reverse does much. This past weekend, just to see, I pulled into reverse at arround 30 and leaned a bit on the throttle. I had my trim full down to direct my reverse blast foreward as much as possible. The bow would immediately plow downward (under if I try hard enough, which I did not). I very nearly had water spray coming up next to my bow light and fwd speed scrubbed off immediately. I was at idle speed in just about 4 boat lengths from about 30 MPH. I found to easilly go to reverse, I had to completely idle the engine but then could drop right into reverse and step on the throttle while holding in rev. Definitely different, and very good.

[Aluminum Squirt]

SmokinLowriderSS, I don't have a reverse but a friend of mine has a 23' North River Commander (aka very large all aluminum utility jetboat with a windshield). He can go from about 35MPH to 0 in about 2 boat lengths and put a huge wall of water over the windshield and into the boat. Its a nice little cool off on a hot day and the massive bilge pumps clean out the hull in about 30 seconds. Probably not recommended in any low profile lake boat, but a pretty fun ride-Aluminum Squirt

[Mighty Thor]

Just for the heck of it I will add my .02. Every used boat I have aquired in the last 2 years, that being the summ total of my boating experience, has had the Pitot tube broken in one way or another. Usually this happens by contact with the trailer while loading or unloading. On my first boat it was just the tip that was snapped off and I had a heck of a time figuring out what the problem was. After you see a good Pitot tube it becomes instantly clear how the whole thing works and You will know right away if yours is broken or not.