Need an engine, not sure what to choose...

[Noodleman]

Hey guys!

I am on the process of a complete re-build of my boat. I recently picked up a Ring 18, which is in quite good condition.

Its undergoing a new paint job, and complete refit inside at the moment.

However, I need to get an engine for it, and I am having a hard time deciding what I should go for.

I have a budget of about ?2000, which rules out a new engine. I have read a few people have put up to 250hp engines on the ring 18 boats, however I have not been able to find many articles on it, or find many people who have worked on them before. I also believe that a 250 is way outside of my budget, and would also be too large on the boat for me.

So, I am looking for some advice about how I should go about choosing the right engine for my boat. Does anybody have any experience with Ring 18's?

 

[Rickairmedic]

Re: Need an engine, not sure what to choose...

Noodle I am going to guess that a Ring 18 is an 18 foot boat if thats the case 100-125 Horsepower will be plenty quick enough for you . My 16' Starcraft has a max rating of 85 HP part of that is that it is Aluminum and lighter than a similar fiberglass boat . I am thinking yours is a trihull if I remember correctly I had a 17' Larson Trihull with a 120 Mercruiser I/O setup on it so I would say a 125HP outboard should be plenty.



Rick

 

[Noodleman]

Re: Need an engine, not sure what to choose...

Noodle I am going to guess that a Ring 18 is an 18 foot boat if thats the case 100-125 Horsepower will be plenty quick enough for you . My 16' Starcraft has a max rating of 85 HP part of that is that it is Aluminum and lighter than a similar fiberglass boat . I am thinking yours is a trihull if I remember correctly I had a 17' Larson Trihull with a 120 Mercruiser I/O setup on it so I would say a 125HP outboard should be plenty.
Rick

Hi Rick,

Cheers for the info. Sorry im being a bit vague, but I have to admit, I am having a hard time finding any info at all about the hull I have, so do not know the suggested max engine size etc.

You are correct, it is an 18ft speedboat. I have had a hunt around the web, and found an image of another ring 18, same as mine, except interiour and windshield (im getting a custom one made).

Its an ebay item, but will give you an idea of what I am working with.

http://cgi.ebay.co.uk/Ring-18-Hull-Trailer-Only_W0QQitemZ140348321622QQcmdZViewItemQQptZUK_Power_Boats?hash=item20ad696f56&_trksid=p3286.c0.m14

I am considering a Mariner outboard, mainly because I recently spent some time working on a Mariner engine, so have a reasonable idea how they work. But, would you suggest any other type?

Also, I have seen some engines being sold as "Extra long shaft". Until I spotted those, I didn't realise they existed! Is there a good method of finding out the exact size (physical dimensions) of engine I should be looking for?

Cheers

 

[Rickairmedic]

Re: Need an engine, not sure what to choose...

Noodle thats a sweet looking boat actually looks alot like a Checkmate . I would say a 125HP motor should make her fly along . The shaft size is pretty easy actyally measure from the top of the transom where the motor will mount to the bottum of the hull. This measurement will either be around 20 " or around 25" this will tell you what size shaft you want on your motor . 17-22" measurement would be a 20" shaft 23" - 27" would be a 25" shaft . Those are the 2 main shaft sizes on an outboard. The only thing I can tell you about Mariners is I have not heard alot of good things about them . Other than that I have 2 Mercury outboards and there are alot of fans of Johnson and Evinrude outboards around here.



Rick

 

[allpoints360]

Re: Need an engine, not sure what to choose...

I have read a few people have put up to 250hp engines on the ring 18 boats

The US equation for hp max for a planing hull is (2 x L x W) - 90 = max hp.

To get the hp to 250, your 18ft boat would need to be almost 10 ft wide! Probably closer to 7?

Measure your greatest beam aft and do the math.

 

[redfury]

Re: Need an engine, not sure what to choose...

I'd go with a motor that is the most commonly found, most commonly found to have mechanics in your area that know how to work on them. If you have a guy that is a certified Suzuki mechanic and the nearest Mercury mechanic is an hour drive away, I'd look for a 'zuki. I've got an Evinrude/Johnson mechanic literally 3 blocks away, so I'll be targeting on of those motors when I look for mine.

Your budget should be able to put you into a very nice running older motor, just keep your eyes peeled. If you are into the project and it's going to take you a year to complete, just keep waiting for that "right" motor to show up. I've seen 4 or 5 of them as I've worked on my boat, but I didn't have the funds available to go get one of them, but I know that if I keep looking, there will be more "right one's" to choose from.

In the mean time, read the forums for your favorite motor brand and get to know the quirks about them.

 

[Bifflefan]

Re: Need an engine, not sure what to choose...

The US equation for hp max for a planing hull is (2 x L x W) - 90 = max hp.

To get the hp to 250, your 18ft boat would need to be almost 10 ft wide! Probably closer to 7?

Measure your greatest beam aft and do the math.

That doesnt work for my O/B boat.
I have a 16' long by 6 beam Max rated for 100 HP.
By your math mine is rated at 192 HP

 

[allpoints360]

Re: Need an engine, not sure what to choose...

That doesnt work for my O/B boat.
I have a 16' long by 6 beam Max rated for 100 HP.
By your math mine is rated at 192 HP

I get 102hp when I do it. (2 x 16 x 6) - 90 = 102

But your actual measurements might be slightly less, say 15' 11" L or 5' 10" beam. The rated HP is usually rounded up to the next 5hp.

 

[Bifflefan]

Re: Need an engine, not sure what to choose...

I get 102hp when I do it. (2 x 16 x 6) - 90 = 102

But your actual measurements might be slightly less, say 15' 11" L or 5' 10" beam. The rated HP is usually rounded up to the next 5hp.

Your right,,,, I totally missed the -90 part...
I think im A.D.D. LOL

 

[tashasdaddy]

Re: Need an engine, not sure what to choose...

i would say that particular style boat had a 140 hp originally.

 

[Noodleman]

Re: Need an engine, not sure what to choose...

Thanks guys, some good advice in there and certainly some things for me to be thinking about.

I will measure up soon and do the math and see what it comes out as.

Also very handy advice about the length of the engine too. Thanks

i do not mind waiting a few months for the right engine to come along, I want to make sure i get it right first time. I have been stung on a used outboard before, and do not want to make the same mistakes again. Thus, lots of questions!

Once I've done the math I will let you guys know what it comes out at, and see if anybody has any suggestions.

Thanks for all your replies

 

[ezmobee]

Re: Need an engine, not sure what to choose...

The only thing I can tell you about Mariners is I have not heard alot of good things about them.

Rick, there are some exceptions, but by-and-large Mariners are rebadged Mercs.