1985 mercury 25hp xd ?

[zseverns]

So I took my boat out this weekend to do a little duck hunting and my trim tab fell off is this a major part? The motor ran fine after just need to raise it some so it will plane out better. Also is there any performance things I can do to get more power?

 

[crazymanme2]

Without trim tab there will be more pressure on the steering.

To get more out of your motor you can bump the timing up to get more rpm's out of it but you will also sacrifice reliability.
You be better off playing with your set up to find optimum performance & speed.Cavitation plate should be even or above the bottom while making sure you're still pumping water.

 

[zseverns]

Ok I'm goin to raise it up some and see how it goes. I didn't know if I could add a bigger carb or anything like that. I might be happy with it after that. I just took it off a light 1432 and put it on a heavy 1542 so that is big difference. It would really fly on the 1436 and I didn't see how fast I got up to but will next time I will.

 

[JMichael]

The trim tab is also the anode, so you might want to replace it for that reason even if the steering pressure isn't an issue.

 

[shawnfish]

So I took my boat out this weekend to do a little duck hunting and my trim tab fell off is this a major part? The motor ran fine after just need to raise it some so it will plane out better. Also is there any performance things I can do to get more power?

cross reference your components and see if bigger carb is possible. i put a 35 carb on my 25 johnson but the intakes,cylinder,pistons etc... on the 35 are the same as the 25 besides bigger carb.

 

[zseverns]

How fast should I be able to go with a heavy 1542 Jon boat

 

[JMichael]

That's going to depend on how heavy, prop, and some other factors so there's not set speed it should do. If I were to guess, I'd expect to see something between 21-26 though.

 

[zseverns]

How do I go about finding out what kind of prop I have on my motor now