Loss of power trying to run onto the trailer.

chitwood46

Recruit
Joined
Sep 7, 2003
Messages
5
I have a 1997 Mercury 200 EFI on a Ranger 488VS. I have a Trophy 25 pitch prop that has been race tuned. (Thinned, sharpened, cup changes for bow lift) The motor has Boyeson reeds installed and is on a Bob's Machine 6 inch hydraulic jackplate.<br />Motor SN is 0G451821<br />The motor will put the boat on plane in about 5 seconds. As the boat is almost up we get just a slight blowout of the prop but not bad. It will run up to 5800 RPM at wot. The 5800 rpms produces GPS 63.4 MPH with fuel and full gear loading.<br />It takes quite a long time to achieve WOT (5800).<br />The most obvious problem is that when I try to run the boat up on the trailer(which is 2/3 submerged), the motor will only achieve about 2000 rpm with the throttle wide open? The boat will not slide up; the last 4 to 6 inches. I would describe the feeling as "it feels like I am getting about 30 HP out of that 200HP."
 

roscoe

Supreme Mariner
Joined
Oct 30, 2002
Messages
21,821
Re: Loss of power trying to run onto the trailer.

Could the Rpm be limited by the amount of trim you are using, ie a safety feature?<br /><br />Probably a good thing, or you'd be doing the Chitwood stunt show, jumping over your tow vehicle. :D
 

chitwood46

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Sep 7, 2003
Messages
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Re: Loss of power trying to run onto the trailer.

Thanks Roscoe, I have the engine trimmed up some but not outside of the motor side supports. It is within the trim microswitch limits. I have jumped a few things but not the trailer, yet! If I could just get more power at the trailer? I suppose I did indiate my age with the chitwwood thing. :rolleyes:
 

wezie

Petty Officer 3rd Class
Joined
Jan 31, 2003
Messages
79
Re: Loss of power trying to run onto the trailer.

Too much pitch. You went for max speed and that takes away from power.<br />Might carefully try to lube the trailer bunks.<br />Then there is the old winch!<br />Good Luck!
 

jim dozier

Lieutenant Commander
Joined
Jan 8, 2003
Messages
1,970
Re: Loss of power trying to run onto the trailer.

Just buy a different prop and every time you want to put it on the trailer, stop get out, take the prop off and switch props to the lower pitch, what could be easier :D . Or you could just winch it up like the rest of us common people.
 

Skinsk

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Aug 31, 2003
Messages
128
Re: Loss of power trying to run onto the trailer.

Doesn't your trailer have a winch?
 

chitwood46

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Joined
Sep 7, 2003
Messages
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Re: Loss of power trying to run onto the trailer.

The winch thing has been done. I have stripped the gears on three winches trying to move the boat the last 3 inches. I am handicapped and am unable to jump out and wind it on properly. My wife, at most ramps, is unable to winch the boat up unless we leave it in the water so she has to wade to get to the winch. The boat did not do this before. Last year I had to be careful or I would hit the winch post too hard. I had it straightened once. It would push it on in the past and now it will not??<br />Thanks for the feedback. I know there is a simple solution out there!<br /><br />I have begun to tell my wife we need to get a new 521 with a 250XS to correct this problem. :D
 

kenimpzoom

Rear Admiral
Joined
Jul 13, 2002
Messages
4,807
Re: Loss of power trying to run onto the trailer.

Besides the slow acceleration, was there any other changes from last year? Did your MPH drop? Was the setup (prop, trim, jack plate) exactly as before?<br /><br />I dont have any answers, only questions that need answers so that others may help.<br /><br />You could do some simple things in the meantime, like check the compression and look at the spark plugs. Check for spark on each plug and take a good look at all hoses and wires. Change all the fuel filters and water separator.<br /><br />Ken
 

chitwood46

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Joined
Sep 7, 2003
Messages
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Re: Loss of power trying to run onto the trailer.

Yes,the prop, trim and jack plate were the same. I did have boyeson reeds installed this spring but the motor performed well before and after the installation. I believe it has been deteriorating performance just this year? It has mainly reached an intolerable level. The dealer found the throttle position module (TPI) was way out of adjustment but upon adjusting back to proper settings, the motor did not improve at all! The dealer has checked compression. Thanks for the fuel filter and water separator ideas. Will go there next.
 

jim dozier

Lieutenant Commander
Joined
Jan 8, 2003
Messages
1,970
Re: Loss of power trying to run onto the trailer.

Maybe you should check the alignment and condition of your rollers and supports on your trailer. It could be that something has shifted and is preventing a smooth roll on of your hull. If you boat can get up to 60+mph I don't think lack of power at the ramp is your problem. Also, you may wan't to look into an electric winch, it would save your wife's back and allow you to finish the last bit if the boat won't drive it up.
 

marinegrh

Petty Officer 2nd Class
Joined
Sep 1, 2003
Messages
196
Re: Loss of power trying to run onto the trailer.

there are plastic plates made for pontoon boats to ease the on/off of the vessel, maybe this would help you in your case, just watch out and make sure the strap is off so the handle doesnt do 100mph when backin down, <br /><br />fair winds and following seas
 

Hasbeen

Petty Officer 2nd Class
Joined
Aug 29, 2003
Messages
167
Re: Loss of power trying to run onto the trailer.

Not to be a smart @!%&@, but why not just back the trailer a little farther back?? Must be an obvious reason!<br /><br />Hasbeen
 

chitwood46

Recruit
Joined
Sep 7, 2003
Messages
5
Re: Loss of power trying to run onto the trailer.

Probably not a smart thing to say but my wife is not yet a precision trailer backer.LOL But then she has improved tremendously from where we were. Actually, then we have the issue of the bow being too high or too low relative to the bow eye and the bow roller on the winch post. <br />The motor is just not handling it now and it used to. Oh ya, it is a bunk trailer.<br /><br />I want to thank everyone for their advice here. The dealer has switched props and is telling me it made a big difference. He said he went to a 23 pitch 3 blade and it ran right up.? I pick up the boat tomorrow. Not really satisfied but what can you do? <br />Thanks again.
 

jdkzrt

Petty Officer 3rd Class
Joined
May 26, 2003
Messages
83
Re: Loss of power trying to run onto the trailer.

C 46 <br />I believe your blowout is a little worse than you think (theoreticaly you should be doing 73+mph). If your engine has a 1.87:1 gearcase ratio, your slip is about 16%. I have read that around 5% is where you want slip to be. <br />You need less pitch on the prop. Try 21" or 22", and don't lift the engine quite so high. You will get better bottom end and be able to pull 6000 rpm with way less blowout.<br />I've got a lift on my boat, and I've leaned alot about going faster by playing aroud with a couple of different props (highest pitch plus highest rpm doesn't always equal highest MPH) ;)
 
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