Motor height

[morb]

I'm a compleat noob when it comes to boats and have been doing a lot of reading. I read about motor height and how it can affect performance. The anti ventilation should be even with the bottom of the boat (from what I have read) Mine is about 2" below the bottom, if I raise it the motor mount is off the top of the transom. My question is, will this be ok? I thought I would have to shim it up or will I not be able to raise it? Thanks Ron

 

[Barramundi NQ]

Hello morb, motor height can be critical to a number of set ups . However there exceptions. What motor and boat combination fo you have? A photo from your photobucket account will help us out immensely.
Cheers from Australia

 

[morb]

Hi Barramundi It's an old 14.5' vanguard boat with an old 70 hp Johnson. I raised it up so that it is even with the bottom, here is a pic of the mount and transom

 

[roscoe]

That is perfectly fine.

You're using 4 bolts through the transom, correct ?

 

[Barramundi NQ]

Can you send a photo showing the height of your anti cavitation plate in relation to the bottom of your hull? With your engine down as low as it can viewed from behind?

 

[morb]

Yes I have 4 bolts through the transom. I'll take the pics you requested tomorrow, it's too dark out right now. Thanks for the help

 

[morb]

Something I was thinking about. Should I shim up that space? I thought it might help take some of the load off the bolts.

 

[Barramundi NQ]

No need. There is no leverage on the top edge of the transom. It is all transferred through the 4 bolts you have already. It's very common to have a gap as the leg height takes precedence over contact with the top edge. Smaller motors, often called portable outboards are small enough to lift off when you go bush or a long drive on a dirt road. Your 70hp is a permanent fixture of the boat. As such it should have been set up correctly. The photo will tell all. Try to get the angle of the pic straight through the anti cavitation plate and one through the middle of the prop. It all sounds good but if you want to be sure for yourself, its always good to know the why.

 

[morb]

she's old beater that i'm trying to fix up so i'm learning as i go. i got the motor running really nice, now i have to work on cleaning it up and some minor fixing.
here are the pics of the motor and hull



the stick shows where the anti cavitation plate is in relation to the hull

 

[crb478]

You are fine where you are at and do not need to shim. Take the boat out and try it out, see how it handles and steers. I suspect that you are where you need to be, but all boats are different. It is possible you need to go down a hole. If you have handling problems experiment. It is free except for your time.

 

[morb]

Thanks for the info. I'm going to take it out this weekend and give her a go.

 

[Barramundi NQ]

Looks spot on.