Slow rpm increase?

[airraider]

I have a 83 merc 50 inline 4 , Took the wife out in the boat today for the first time and it ran fine the first mile. When i slowed to idle i noticed the trim tab got stuck up and the motor was trimmed all the way up . The next run of about a mile was very slow. Could only get about 3000 rpms then it would VERY slowly increase , maybe 500 rpms a minute? Did running the motor trimmed all the way up cause the damage ? Any help would be appreciated..

 

[j_martin]

Re: Slow rpm increase?

If it got high enough to lose water supply, you betcha.

 

[airraider]

Re: Slow rpm increase?

it was trimmed up high but was still getting enough water to pee a steady stream

 

[j_martin]

Re: Slow rpm increase?

The other thing that sticks them at WOT is fuel starvation.

At this point, you need to check compression to see if you have any serious damage.

 

[airraider]

Re: Slow rpm increase?

j martin.. just got done running a comp. check all cylinders checked to be 91-94 ... i did however hook the motor up to the hose and noticed this.... water leaking from the bottom of the motor

 

[airraider]

Re: Slow rpm increase?

not really sure if the leaking water would have anything to do with the slowness to gain rpms and gain speed but just something i observed recently

 

[j_martin]

Re: Slow rpm increase?

Compression sounds low, if your gauge is accurate. Water leaking out of the top of the mid is a sign that the water delivery tube is not connected, ruptured, or a seal on it is missing. I still think you overheated and stuck it.