Engine height

[Scottimus]

Hello all, I know there has been some talk about this lately. It got me thinking and checking (and knowing, never thought about the engine height!)

So, my question is, is my engine mounted too high? I read on here that it you start off with it being around 1" below the keel, if that is the case then I am way to high, if it is supposed to be the bottom of the transom then I think I am too low.

Thoughts/opinions?

 

[Scottimus]

Re: Engine height

oops, think I posted this in the wrong topic...Sorry...

 

[Sea Rider]

Re: Engine height

Specified engine/hull heights on manuals are just guidelines and irrelevant, it's a matter to fine tune engine/transom height parameters once on water. To check, go for a water ride with your boat/engine set up, distribute weight, passengers evenly transom to bow, adjust thrust rod to a hole position in which will have boat, cav plate paralell to water line when boat is on plane at wot.

Once you have this setting ok, have a mate check your tail, ideal undisturbed flow is achieved when water passes slightly under small upper plate, if passing above will have water splashes at transom's back and more tail drag against water flow. This also applies when using long shaft engines mounted on short transoms. If passing near cav plate will have excesive cavitaion on choppy seas and at tight turns. This applies when using short shaft engines mounted on long transoms. Correct engine height is essential for pursuit of best performance & speed at plane or wot for any boat.

PD: The tail miron must take caution when checking, nobody wants him falling into sea at wot and me having attention calls for giving dangerous testing examples, he could knee on transom's deck, grab hold from something and have a look and depending on the water flow condition seen will need to raise or lower a bit engine on transom.

Happy Boating

 

[Bob_VT]

Re: Engine height

Based on your hell design..... you should be fine

 

[gss036]

Re: Engine height

I agree with Bob, you look ok to me.

 

[Lyle29464]

Re: Engine height

move engine up till it vents in a hard turn.

 

[Scottimus]

Re: Engine height

Thanks for the responses all. I do want to check it when at WOT but the thought of hanging over the back of the boat while at WOT isn't high on my list of things to do before I die I will have to get someone to drive that I trust so that I don't end up in the drink...

Thanks again for your responses

 

[Sea Rider]

Re: Engine height

Don't worry, won't fall overboard, to take the nail out, will need to do it to fine tune proper engine height as you can't know by just looking a posted pic. To match correct engine height parameters also depends on hull shape, as all boats are not built the same. We perform this test constantly on sibs/ribs with up to 50 HP engines to better top speed and performance, anyway is much faster to modify transom height on these type of boats if needed, than doing same on the type of boats you guys use.

Happy Boating