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#1
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200 Optimax low RPMS
Hi, I am new to this forum and new to owning a boat. I just purchases 2001 Ranger 619 with a 200 HP Optimax motor. I have had the boat out twice and and can only get it up to about 45 MPH (GPS) at 4800 RPMS. It has a Tempest Plus 21P Prop and a Power Lift Jackplate on it. I have tried running the boat at several different trim positions and have raised and the lowered the Jack Plate and it just wont seem to break 45 MPH. The previous owner said he could get 62 MPH out of the boat on his GPS. I could under stand myself only missing his mark by 5-7 MPH as I am a novice but 15 MPH something just seams wrong. The boat starts and runs fine, and runs very smooth through all the way up to WOT at 4800 RPM. After talking with him he said he would get the best performace with the Jack Plate as far down as it would go and a trim postion of just over 5 on the smart gauge. If anyone has any ideas on why I am not getting the performance he said he was or why I am not breaking 4800 RPMs that would be very helpful.
P.S. The motor was rebuilt in 2004 and now has 400 hours on it. Thanks in advance. |
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#2
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Your running the the right prop. May want to have motor checked out.
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#3
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I think you are right
I pulled the plugs tonight and they all looked a little fowled. One was much worse then the others. They all did have white build up on the center and side electrodes so hopefully this will this is a false positive on real operation. Thanks for the motor advise propman.
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#4
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Your not getting the RPM's you need to run the speeds your expecting to start with! I realize your new to this boat, and you said your new to owning a boat as well, so to start with, time on the water and time behind the wheel of a performance boat will teach you many things! As Propmann stated, it appears your running the right prop so taking the prop out of the equation, here are a couple of suggestions for you to utilize to possibly get those higher speeds your expecting.
Motor height (at planing speed) is pretty critical and a good general rule of thumb is to have the motor height such that the cavitation plate on the lower unit is even with or slightly higher than the bottom center of the keel (bottom of the boat)! This height will generally give you good all around results. With your motor at the correct height, you will find the trim function can make or break the speed you can attain. Forget about the trim gauge, your ears and your eyes are your best allies here!!! After your boat is on plane and under full throttle begin to trim the motor "up"! The nose of your boat will begin to rise slightly and you'll notice the side spray beginning to move further back and you'll notice the RPM's beginning to climb! When you see & hear the RPM's make a sudden jump, you are pretty much at your "sweet spot" for maximum speed. You should be throwing a bit of a rooster-tail behind you! If it is about motor height, usually that's just about perfect! Much above motor height you are beginning to get slippage at the prop so trim back down and adjust your "tail" so that it is in that engine height "zone"! How your boat is "loaded" will affect all the above, so each time on the water you will have to make minor adjustments in regards to amount of trim needed to obtain best results! Water and wind conditions all play a part as well, and practice along with good common sense are warranted each time you go out! It'd be a lot easier to spend five minutes in the boat with you than trying to explain here, but hopefully you can utilize what I've tried to explain and get the performance your seeking! If possible, you might try to arrange a tad of time on the water with the guy you bought the boat from and pick up some pointers from him as well! Good luck,,,,,,,,,,,,,,, and be safe!!
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Lowrance Simrad PowerPole |
#5
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sounds like you might be running on only five clynders. that model year optis can be a real bugger they had one hole that would score i think from a problem with the cooling wouldnt let that one warm up even.
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Tags |
low rpm , optimax |
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