Need help mounting motor???

[NMregatta]

I have a '89 135hp that I just bought to replace my inline 6, its a long shaft outboard, my transom is short. What I would like to know is, what kind of jack plate should I use to get the prop towards the top? Or not at all? What height should it be from the prop to the bottom of the transom?

Thanks,

Loal

[AlaskaStreamin]

You'll have to go up 5" just to make up for the extra length in the motor. Then another 8+" to get the propshaft close to even. That's 13+". What kind of boat are you working on? Man that's alot of height. At the minimum you will need to add some transom tie bars or the leverage will tear the back of the boat off. I don't know of any jack plates that give that much lift. You may have to get a set back plate with 5" of lift (Like Land and Sea's Step-N-Jack) then add your jack plate on that. Good luck and be careful!!

[Techno]

Somebody moght know how high but you didn't mention what your running.
If you beef up your transom you could mount the jack plate to 2 pieces of aluminum angle. That's pretty much what the manual jacks are made from.
Something to think about is will your boat float the engine out of the water with the set back. If you know what I mean.

[Greg Moss]

man what about raising the center of gravity that high? If it ever starts chine walking will it roll over? best bet would be make it a short shaft motor or find a different motor. to make it short shaft would take a different mid section and have the drive shaft shortened. would be better than jacking that thing up that far.

[Rickracer]

Either convert to short shaft, or sell that motor to somebody who needs a long shaft, and get a short shaft. The combo you have now is going to be a real hassle at best, and possibly downright dangerous at worst.

[Liqui-Fly]

Been down that road because like you it was what was on the motor I ended up buying. You will spend more dollers trying to make it work in the long run than you would be going shorter right from the start. Make a lot of phone calls and see if you can make a swap. There are just as many guys looking for long as there are short. Don't try to make it work because it won't!!!!! Look at the suggestions already...transom reinforcement, jackplate, aluminum angle,probably longer steering cables too. In other words cha, ching, ching. After you go through all that your boat still won't be properly rigged cause like Greg said you'll now have a high center of gravity. Lived and learned, LF

[NMregatta]

Thank you all for the help. This is just what I was afraid of. I bought the motor from a guy in Florida, and I'm in New Mexico. Trying to find someone to buy the motor here is next to impossible. Where can I find a short mid-section, and what is involved in shortening the shaft?

Thanks again,

Loal

[Liqui-Fly]

The motor generally has an extension plate on the lower unit. If this is what you have you may be in good shape. Now to get our nomenclature straight by long you mean the 25" right? Technically I think Merc refers to this as the extralong shaft. Then the 20" is the long shaft and a 15 I guess is the short shaft. Pull your lower unit off. If there is a 5 inch adapter it will be between the lower unit and mid section. If you are really lucky you'll have a two piece drive shaft. If this is so then you're golden because the extension will just slide off and you'll have the correct shaft length. If not I would try swapping with someone that needs the long shaft but the labor for removal and putting it back in can be costly also. The shaft can be cut and resplined by Jay Smith or Eagle One. The water tube is easy because it is just copper pipe and you can cut that yourself. The shift shaft may have an extension also but it may also be one piece. Then last but not least you'll need new (shorter) mounting studs for the lower unit. LF

[Liqui-Fly]

To answer your prop shaft to the top of the transom question....well it depends on what you want...22" to 28" is a ball park figure. LF

[NMregatta]

Thanks,

I think (just guessing) the transom is probably only at the most 16"-18" tall. I have a 16' 1967 regatta ski boat. I just want to set it up as close to right to start with.

Thanks again,

Loal

[NMregatta]

oh and the shaft is 25"...extra long?

Thanks,

Loal

[Greg Moss]

I woould need the serial number to tell you what mid you have for sure but if it is a 89 then the mid is not that easy to shorten. The older 25" motors had the 5" spacer in them yours i think has the internal trim(between the clamp brackets) if it does then the whole thing is easier to replace than try to shorten. Some one on this board will have a 20" mid for sale all you have to do is post on the parts wanted board. Then have the drive shaft shortened by eagle one. The labor to remove the shaft will not be that high. If it is a fresh water motor it should only take 2 hours to remove it and replace it. that would be the best bet for your problem. Greg

[Liqui-Fly]

On the labor I had problems because they had a hard time removing the bearing carrier because the motor came from salt water. Actually I was so lucky they had to bust open the housing to get guts out. Thankfully I was able to score a nice CLE housing on e-bay for $250. LF

[Greg Moss]

Fly I have seen that more than once. I am on the Texas Gulf Coast, Boy you wouldn't believe how much acetyline and oxygen I go through. I think my favorite tool is my Snap -on air hammer. All people have to do is read the owners manual before they stick it in the glove box for all the pages to stick together. Under main. it tells about pullinjg the bearing carrier every year and cleaning and greasing the housing and nut then replace it and retorque it. stuck powerheads you name it if it gets stuck from salt i have had to get it apart. sometime though I have to give up and salt wins not very often but sometimes. Anybody that livbes around the saltwater and does not use Salt Away is asking for big labor bills when it come time for any repairs. I have found Salt Away to help Cut down on corrosion all most to nothing with regular use. Believe me when I tell you guys this It helps.If you use your boats in water that has anysalt content you need to use it. It keep the cooling passages clean as new and will keep the motor easier to service. Sales pitch over Good Day Greg