Spray behind boat

[xtremefisher1]

hi everyone. my question is, i have a 1985 9.9 short shaft johnson on a 12 deep and wide with a 15 inch transom. no matter what i do i have spray that comes up on either side of the motor at the back.\

what could i be doing wrong to setup my motor so it doesnt do this. i have tried every setting on the pin and it still does this.

any help is appreciated

 

[NYBo]

Post some pictures of the motor showing its relationship to the transom and bottom of the boat. Is there anything else attached to the transom below the waterline?

 

[foodfisher]

The antiventilation plate should be even with or just above the keel line.

 

[airshot]

Had the same problem with my 9.9 on my 14 alum hull. I ended up making a small stainless steel fin that attached to the ventilation plate to make it a little larger and the problem went away. You might try raising or lowering your motor on the transom, only a small change may be needed.

 

[ssobol]

The antiventilation plate should be even with or just above the keel line.

The antiventilation plate should be at or just above the water when the boat is cruising on plane. The may or may not be level with the keel line.

 

[Texasmark]

There is an inherent problem with anything vertical in the water at speed. Most engine mfgrs install a plate above the AV plate that protrudes out from the leading edge of the lower unit whose purpose is to deflect this water. If this plate is not above the surface then it is useless and you will have water coming up from below. If your transom is a standard 15" and you have a 15" short shaft lower unit engine mounted fully resting on the top of the transom, then all the plates should be in proper position, for a 10 hp power plant anyway.

HTH,
Mark

 

[xtremefisher1]

thanks for all respomses, i have done an internet search and found that i am 2 inches to low.. others with the same problem had to raise the engine as do i.. i will post a response once i have water tested.. thanks for all the help