Jack plate info needed

[brappley]

Well it started the second time I took it out last season, I noticed if I trimmed it up bout 5 deg to bring down the bow to plan out the boat I noticed I could here a louder exhaust noise , in fact my wife noticed it first. That's when I started looking into different things that could be wrong, then my boat dealer in Freeport IL, mentioned the jack plate and couldn't figure out why they put it on. That's what got my curiosity spiked.
I let it go for the rest of the season and started looking at it again a few weeks ago.
Then I started my research with the jack plate hight and the setback of the motor. The only thing I can figure out is it should have a short shaft instead of a long, that's why they added the jack plate to raise it up to normal highs.
That motor won't fit with out it. So now to get that high corrected. Kind of wondered why a 1998 boat had a 1996 outboard,
So my research begins,
I just need the correct info before I start drilling holes in my jack plate .
All you guys have been great teaching and asking me questions and I'm sure I'll figure it out.

 

[fhhuber]

Looks mounted high to me...

Nice thing is you can fairly easily lower it 2 inches to try and see if that helps.

Rules of thumb are to get you in general ballpark. Then you have to adjust ONE THING AT A TIME and compare results.

When doing lake testing you need the boat loaded the same (close as reasonably possible)

 

[Dukedog]

if it didn't do it at first then maybe ya dinged up tha prop tha next time out... up trim raises tha bow..down trim brings it down.. if tha exhaust gets louder then ya may be goin' to far (prop will blow out also) or tha motor is to high.. tha "L" in tha elpto designates a 20" which is sometimes called a short which it isn't.. 25 is single XLand 30 is a XXL.... it does look like a 25 though

ELPTO..

Electric start, long shaft (20"), Power trim, Oil injection....

 

[brappley]

Dukedog
After adjusting the jack plate up 1.750 inches, I tested it out yesterday, it came up on plain quicker and ran at 5250 rpm at 34 mph per my gps, much better performance and was able to trim up the motor with out out any issues , I think I'm going to go ahead and drill the other holes in the jack plate to see if the add 1.500 inchs will help to get my 5400 rpm. It won't be for a few days but I'll update when I get it done.

 

[Dukedog]

you really need a water pressure gauge!......

 

[brappley]

I can do that , just have figure out where to connect it since the speedo is connected to the lower part of the motor housing , do I tap into the pee hose ?

 

[Dukedog]

don't remember on tha inlines but sure Fazbullet or some others here can answer that... not tha pee tube though...

don't know if i'd drill more holes in tha jp??? how much metal will be left above tha top holes after ya drill 'em???

 

[brappley]

Ok thanks, I did see a port not used in the water jacket that's a 1/4 - 20 thread that's not used.

 

[brappley]

don't remember on tha inlines but sure Fazbullet or some others here can answer that... not tha pee tube though...

don't know if i'd drill more holes in tha jp??? how much metal will be left above tha top holes after ya drill 'em???

There is over an inch above the top hole in the mounting plate, and one more hole in the engine mount, so together with raising to the next hole in the engine mounting plate and drilling the second set of holes it would give me 1.750 inchs higher. There's more than enough metal above the mount to drill another set of holes safely. Just my opinion.