Horizon 195 speed issue

[Pikey23]

I have an four winns 195 horizon cuddy with a 3.0 mercruiser and an alpha 1 out drive. I have changed prop sizes and pitch multiple times. But I get the same result. 30-31 miles an hour and 4000 rpm. It does not matter if I have 3 people in the boat or 6, Still 4000. Pulling a tube or skier gets the same thing. If i put it in neutral it revs over 4000 rpm. So I know that the tac will go over 4000. Does anyone have any idea what the deal with this is? Thanks in advance.

 

[Don S]

Re: Horizon 195 speed issue

Could be a lot of things. Does this 195 have a year?
Here is a list of possible causes of low WOT. Best to check each off as you check it as a possible cause. Have you tried trimming it out?

http://forums.iboats.com/showthread.php?t=295070

 

[Pikey23]

Re: Horizon 195 speed issue

it is a 1984 four winns. I looked at the list on the link.
I figure that the list below can be possible causes. How do I check the first one and second on my list? What should the fuel pressure output be? Thanks


Restricted fuel pickup tube or anti siphon valve Fuel System Test
Restricted exhaust system (broken exhaust shutters/flappers) in engine transom shield or drive
Poor cylinder compression Compression Test
Carburetor defective, or wrong type.
Fuel pump pressure and vacuum
Engine timing and ignition system operation