Is my engine mounted low enough?

[racerone]

Strange how people come looking for suggestions and then mock the people offering the suggestions.----I think adding 5" (12.5 cm ) to the motor is a top notch solution.----Sorry if it does not fit your budget.-----Not going to get much more help on this forum I think !!

 

[KJM]

You must be fun at parties.


I ordered this bracket becuase it allowed to be mounted on an angled transom ( negative or positive up to 35 degrees to avoid having a slope under the bracket). Becuase of this, I think it trades in alot of the lowering it would do if the transom was not angled. It wasn't a cheap bracket so I don't want to get a cheaper bracket and build a slope for it while I already have this. I think its better to try and lower it. I'm going to try flashback's suggestion and redrilling the holes in the wooden board to lower the engine a few cms. It should do the trick. Will update here later if it did or not.

That sounds like the best option. I didn't realize you had a bracket made for sloped transoms.

 

[Sailor96]

Strange how people come looking for suggestions and then mock the people offering the suggestions.----I think adding 5" (12.5 cm ) to the motor is a top notch solution.----Sorry if it does not fit your budget.-----Not going to get much more help on this forum I think !!

You are not contributing to this topic whatsoever. You are either trolling or trying to be a clown. All the people who commented in this topic already helped me plenty so far, can't say the same for you. Will you please stop commenting on me now? You are not only wasting my time but also your own time.

 

[Sailor96]

A man in my marina looked at the engine and said when I apply throttle the transom will most likely go down/submerge a little. I decided to take it out for a spin considering I also have a working inboard engine in case anythings goes wrong. (If you wonder why Im putting on an outboard; basically an auxillery engine as my inboard dipped on me a few times and I had to be towed, currently the inboard works fine but there is excessive vibration coming from the prop or the shaft, I still need to hire a mechanic to look at the inboard but they are hard to find in my area. Untill I fix the inboard, the outboard will be my main engine)

The more throttle I apply, the further the bow rises and the stern submerges. On full throttle, the bottom of the wooden plate almost hits the waterline and my transom does too, even submerges an inch or two.

I went to a wavy area and the prop did not come out of the water at all. However, when I'm stationary at a dock I can notice the prop coming out of the water in waves. My guess is that becuase the engine is being pushed down in the water, when a wave hits its still low enough to not come out of the water.
Perhaps it might be better to lower it a bit but I don't think its necesary.

Thanks for all the advice!

 

[QBhoy]

Hi everyone,

Recently I installed an old mercury 25hp on my sailboat.
The anti ventilation plate is about 1 centimeter under water.

I am worried tho, that my engine is mounted to high.
Does it have to be lower than this or is this fine?

It's a heavy boat (4000kg approx)
The engine also is getting cooled and runs fine.

I’m afraid that it’s not going to be any use at all, whilst it’s like that. For a few reasons…one of which, is that should you find yourself anywhere other than a millpond…it’s going to ventilate the prop. Even a chop or wave height of a couple of inch or so…or should a crew member, move their weight towards the bow…you’re in trouble. Sod’s Law dictates that the occasion tbat you really need to use the engine…undoubtedly will be on a day that ain’t going to be flat calm ! Few other reasons I could go on about too…but I’ll leave you with only one more…and that will do.
Should you need to put her in reverse, in any conditions at all…especially whilst the boat is moving forwards…(should you need to stop the boat at all by engaging reverse)…there is not a chance that she’ll have any sort of affect or purchase from the prop. It will almost certainly just pull air into the prop from the surface instead. Any pics zoomed further out and showing the bracket set up on the transom ?

 

[tphoyt]

And she needs to be able to pump water

 

[Sailor96]

I’m afraid that it’s not going to be any use at all, whilst it’s like that. For a few reasons…one of which, is that should you find yourself anywhere other than a millpond…it’s going to ventilate the prop. Even a chop or wave height of a couple of inch or so…or should a crew member, move their weight towards the bow…you’re in trouble. Sod’s Law dictates that the occasion tbat you really need to use the engine…undoubtedly will be on a day that ain’t going to be flat calm ! Few other reasons I could go on about too…but I’ll leave you with only one more…and that will do.
Should you need to put her in reverse, in any conditions at all…especially whilst the boat is moving forwards…(should you need to stop the boat at all by engaging reverse)…there is not a chance that she’ll have any sort of affect or purchase from the prop. It will almost certainly just pull air into the prop from the surface instead. Any pics zoomed further out and showing the bracket set up on the transom ?

Thanks for your reply and sorry for mine being so late.
It seems as if it is mounted just low enough. Certainly would be better to lower it but I can't really move it much more down.
Also, when throttle is applied, the stern of the boat and the outboard are lowering further into the water. On nearly full throttle my transom touches the water. When a crew member moves to the front it's not a big deal unless the outboard is idling, it will sound weird as the outboard get lifted out the water, however when throttle is applied, the weight of the crew member on the bow doesn't seem to affect the depth of the outboard in the water. I didn't even think of it untill it started to sound off when going for an anchoragee. Reverse also seems to work fine and will stop the boat quicker than the inboard diesel did.

Here is a video so you can see it in action. You can see that its quite low in the water actually when going.

If the video is bad quality check it later when yt finished the hd part.

If I really end up having to lower it, the best I could do is remove 2-3 cm of the upper side of that wooden plate. That would slightly lower the engine but it wont be much.

Here is a picture that might show the bracket setup better. Its taken before putting the outboard on (please ignore the ugly hull, its getting paint soon )

 

[flashback]

The mounting board on the transom needs to be wedge shaped.

 

[airshot]

Unbolt the wood where the motor mounts and lower that a couple inches, just drill new holes in the wood. If you get into some chop you don't want the water intake to keep popping out of the water.

 

[roscoe]

The mounting board on the transom needs to be wedge shaped.

Exactly.

If you place a wedge between the hull and the bracket, so the mounting bracket is vertical, it will lower the motor several more inches deeper into the water.

Problem solved, no new holes in the hull.

 

[airshot]

Exactly.

If you place a wedge between the hull and the bracket, so the mounting bracket is vertical, it will lower the motor several more inches deeper into the water.

Problem solved, no new holes in the hull.

Yep....didn't notice that before....the tilt pin on the motor should be able to allow it to hang verticle after. Any good woodshop can make a nice uniform angled wedge that would look good !

 

[flashback]

You can make the wedge out of Styrofoam, shape it to fit and then glass it.but use epoxy resin, it won't eat the Styrofoam..

 

[flashback]

 

[flashback]

I stoled this picture from a member. It is what you need.

 

[Sailor96]

I actually don't need the tilt pin on the motor to get it vertical. I can alter the bracket to make it vertical after adding a sloped/wedged board.

The bracket is designed so it can be setup for transoms with negative or positive angle up to -35 degrees or +35degrees.

At first I wanted to create a wedge/slope but then stumbled onto this bracket.

Wouldn't it just be easier to alter the vertical wooden board like Airshot suggested?

Also another thing I have not mentioned, the bottom of the wooden board actually nearly touches the waterline when giving full throttle. If I lower the engine, will it push the stern under even further? Becuase then I would be having an issue with the bracket dragging in the water.

 

[airshot]

Interesting mount you have there, not sure I have saw one like that. However that may make the job even easier. Adding a wedge would keep you from drilling more holes, but resealing and getting to the fasteners inside the transom might be a challenge. Rather than moving the wood section down, mabey just cutting a couple inches off may be the ticket !! From the pics, it look like a couple inches could be trimmed off the top of that wood mount then reseal the wood. Should be an easier change than most other ideas so far. Right now your motor is just barely low enough to perform, a couple more inches would be a small safety move to be sure the pump doesn't suck air..

 

[flashback]

Be careful if you go this way, the motor clamps may land in a bad spot..

 

[airshot]

Be careful if you go this way, the motor clamps may land in a bad spot..

Oh yes....by all means do look ahead and see where things will fit....

 

[Sailor96]

Yeah someone suggested that too on the first page on this thread. I thought it was the best idea to lower it. I can measure the distance between the engine clamps and where the metal starts and take a little bit off of that and that's the size I would be able to cut off. It gonna get me probably 5 cm lower.