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 36 PD lost of Speed-HELP!!! 
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Post 36 PD lost of Speed-HELP!!!
Speeds all light.
When Engine \ boat was new ran 29.7 shallow, 28 Deep at about 4040 RPM.
One year later, over 50 hours-26 both shallow and deep about 3900 rpm's.
Bottom end is great but lost top end. The prop is not worn. Checked air filter, sparks - looks OK.
Can trim out to get more RPM's but lose speed.
Any suggestions would be greatly appreciated.

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16 x 48 Alweld - 36 PD FPR PT&T


Mon Dec 07, 2009 12:18 pm
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Post Re: 36 PD lost of Speed-HELP!!!
You might want to check the bottom of your boat to make sure it is not developing and bends from rolling over stuff with the Allweld. Somewhere to start.

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Mon Dec 07, 2009 12:23 pm
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Post Re: 36 PD lost of Speed-HELP!!!
Have you replaced your prop? I gained back my speeds & hole shot with a new prop

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Mon Dec 07, 2009 12:32 pm
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Post Re: 36 PD lost of Speed-HELP!!!
Make sure your governor is set correctly. Should have 4250-4300 rpms out of the water.


Mon Dec 07, 2009 1:00 pm
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Post Re: 36 PD lost of Speed-HELP!!!
Are you running it at a higher altitude than originally? Robs power every time.


Mon Dec 07, 2009 6:29 pm
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Post Re: 36 PD lost of Speed-HELP!!!
adjust your govener set screw to where your rpms in nuetral are 4250-4300 and that should get your 100 rpms back but that is not going to be the reason you lost your speed....look at the bottom of your boat...i bet money that thing is hooked all to shit...that boat is not ment for a mudmotor with its cross bracing and such and thinner aluminum.....good luck.

take some pictures of the bottom of your boat and post em up.


Mon Dec 07, 2009 6:42 pm
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Post Re: 36 PD lost of Speed-HELP!!!
Prop change made a big difference for me. Old prop may look ok but doesn't take much. Start with the prop you will be using it eventually if it doesn't do the trick.


Tue Dec 08, 2009 11:40 am
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Post Re: 36 PD lost of Speed-HELP!!!
prop isnt the problem.


Tue Dec 08, 2009 12:42 pm
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Post Re: 36 PD lost of Speed-HELP!!!
Thanks everyone for the reply's

Tested the governor, 4150
The prop is not worn, running 3910 trimmed to best speed. If I trim up higher, gain RPM - loose speed.
The bottom looks OK, but the transom has about a 3/8" dip in it at the engine.

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16 x 48 Alweld - 36 PD FPR PT&T


Mon Dec 14, 2009 12:55 pm
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Post Re: 36 PD lost of Speed-HELP!!!
Posted this on your other thread, two things, turn up the govenor to 4350RPM out of water in neutral warmed up at WOT. This will help some. That little "hook" ahead of the transom is the other part of your problem. A hook will slow the boats performance, as the hook gets worse or you develop more of them ahead of the cross ribs in the boat, your performance will fall off even more. See if you can beat the hook out or fill it with marine epoxy to help regain performance.

PW

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Mon Dec 14, 2009 6:18 pm
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Post Re: 36 PD lost of Speed-HELP!!!
Thanks for all of the suggestions. Tried a few things, set the governor to 4210, new plugs, new fuel filter and cleaned the carb. Back to original speed, 28.3 light - deep water. Fast enough for now. THANKS again

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16 x 48 Alweld - 36 PD FPR PT&T


Mon Feb 08, 2010 12:13 pm
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