can a older starcraft be reinforced to acept a larger engine?

is this engine a short shaft type?


and is this Yamaha also a short shaft? (attached image)

this boat a 1982 Starcaft MR210 21' 900LB hulls max HP is 140. can extra transome knee brakets and stringers be added to the MR210 or can the orginale transome be seriously reinforced to acept a 250HP.

the newer SC have a max HP of 250 I was curious if a older SC could be reinforced
like the newer models.

I don't like the weight & cost of the new SC.

also can a 250HP engine be dissguised as a 140HP w/ a 140HP sticker and can the coast guard reconize the boat is overpowered? or do they even care? I know a boat dealership won't install anything over the max rating.

STB

Re: can a older starcraft be reinforced to acept a larger engine?

I don't think you will get anything but negative answers on this. Over power by 110hp, are you kidding?

Re: can a older starcraft be reinforced to acept a larger engine?

negative or positive it's all part of learning from the experts.

if all negative on the 250hp please make a suggestion,

edit I have read that this 900LBs hull SC even w/ a 115 is underpowered.
STB

Re: can a older starcraft be reinforced to acept a larger engine?

I would not recommend a 250 at all. A 140 would be plenty of power to push that boat 45-50mph. What are you trying to achieve?

Re: can a older starcraft be reinforced to acept a larger engine?

a combination fishing and sleeper power boat.

that's good to know the 140HP will travel 45-50 that would be fast enought for me.

however if I was able to obtain a newer Yamaha 250 for cheap well I would just like to know all the alternatives.

BTW the bass boat is about twice the weight of the SC and I'm thinking the bass boat travels 90+knots what do you think the SC would do?

Re: can a older starcraft be reinforced to acept a larger engine?

I think it would be unsafe and a rocketship. The motor will also probably cause the transom to sit too low in the water and you will take on water on deck... I think this is a TERRIBLE idea.

1) Yes USCG cares if you break the law. DO the cops care if you speed? Same thing.
2) Can't tell you about the shaft. Measure it. I'm not a yammy guy...
3) What new SC has a 250 rating? what size is it? how much does it way? What's the hull design?

Get a jackplate.. you'll gain a few MPH in top end.

Re: can a older starcraft be reinforced to acept a larger engine?

If you can get the 250 yammy for a realy good price, I would turn around and sell it for a profit. Then find a 140 to put on. If you were to go ove the hp rating I wouldn't go over 150.

Re: can a older starcraft be reinforced to acept a larger engine?

zopperman said:

I think it would be unsafe and a rocketship. The motor will also probably cause the transom to sit too low in the water and you will take on water on deck... I think this is a TERRIBLE idea.

1) Yes USCG cares if you break the law.will the coast guard reconize the boat is overpowered even w/ a 140 sticker? what is the punishment they repo the boat?they DO the cops care if you speed? Same thing. this is one of my favorite parts of boating besides the no wake zone and being a curtious to other there's no speed limit
2) Can't tell you about the shaft. Measure it. I'm not a yammy guy...
3) What new SC has a 250 rating? same MR210 21' what size is it? how much does it way? 1700LBs What's the hull design?V hull complete spec's on the newer MR210 here's a 2007 model just scroll down a bit.
http://assets.mydealeredge.com/brochures/2007/Starcraft-Fishing.pdf

Get a jackplate.. you'll gain a few MPH in top end.

Click to expand...

doe's the bass boat have a jack plate?
STB

Re: can a older starcraft be reinforced to acept a larger engine?

thebrain said:

doe's the bass boat have a jack plate?
STB

Click to expand...

yes

Re: can a older starcraft be reinforced to acept a larger engine?

I have read that relocating the engine (w/ brakets like 2' back) alters the geometery so the boat actualley losses preformance.

this jack plate looks like it relocates the engine only a tiny bit.what exactly doe's the jack plate do?
STB

Re: can a older starcraft be reinforced to acept a larger engine?

thebrain said:

doe's the bass boat have a jack plate?
STB

Click to expand...

STB - There is a speed limit in boating. It's whatever the conditions dictate... whatever the appropriate top speed.. I've seen people get stopped for doing 50 in heavy fog.
They might recognize it. Last time they made me pull the cowling off...

The new starcraft is almost double the weight of your boat...

This is all around a bad idea. Overpowering to a 150 is fine, a 175 is MAYBE ok. but 250 is just stupid.

my 2 cents.

Re: can a older starcraft be reinforced to acept a larger engine?

zopperman said:

STB - There is a speed limit in boating. It's whatever the conditions dictate... whatever the appropriate top speed.. I've seen people get stopped for doing 50 in heavy fog. well these people must have a deathwish or in a big rush to travel faster than idel in fog
They might recognize it. Last time they made me pull the cowling off...

The new starcraft is almost double the weight of your boat... I am reascring this older type SC MR21 mainly for the weight and cost I'll probably end up getting the desired hull then do a repower so I'm researching engines at the same time

This is all around a bad idea. Overpowering to a 150 is fine, a 175 is MAYBE ok. but 250 is just stupid.

my 2 cents.

Click to expand...

OK the 250 is to much. w/ a larger than manufactors max would the transome have to be reinforced w/ 150 -175?
hypothetically speaking if the USCG thoughly inspeacts the engine can they reposess the boat if found to be over powered?
STB

Re: can a older starcraft be reinforced to acept a larger engine?

thebrain said:

OK the 250 is to much.
hypothetically speaking if the USCG thoughly inspeacts the engine can they reposess the boat if found to be over powered?
STB

Click to expand...

I don't think they would impound it, but you would get a hefty fine.

Re: can a older starcraft be reinforced to acept a larger engine?

It's your boat, do what you want. I'm not going to encourage you to break the law. That being said, it's dangerous and boats have a limit for a reason.
Why do you need more than a 140? You'll hit 45 with that... do you want a go fast boat? or a fishing rig? or 42' contender with triple 300 OB's that can hit 75?

Re: can a older starcraft be reinforced to acept a larger engine?

Ask your insurance agent if it's ok to put a 250 on your boat. If you over power your boat at all and have an accident, your insurance company will void your policy and will not be held liable for anything... throwing all liability back on you.

Re: can a older starcraft be reinforced to acept a larger engine?

wahoo.......i get to answer a tinny question......

i usualy keep my nose out of these......but this is a boat question....it has nothing to do with starcrafftts....(is that how you spell it?)

the USCG determins the HP rating by calculating legnth x beam, it has nothing to do with the weight.......that's why bass rockets are looong and wide.

a little trick a few years ago was to change the hp logo on your motor..... they caught on to that one pretty quick and the fines in those cases were double because it was an intentional act.

can your transom be beefed to hold a larger motor.....yes. should it be....no....there are reasons why those rules exist....to save lives.

lets say you decide to go 250 hp.....you beef the transom and hang the motor....re distribute some weight so the boat is flat in the water and not stern heavy......change the prop to a bigger wheel.....say a 24 pitch because the big hp will reach max rpm with lots of throttle to spare.

so now you are running a 24 wheel,,,,,,drop the hammer and the boat takes off like it was shot out of a cannon......

you get up to seed and the boat starts to rock from side to side each time more violently.....you try to slow the boat......but instead, the boat catches an edge faster than a rookie wakeboarder and over you go.....

its called chine walking.....and it is the reason rules exist. it can kill you.
when they designed your boat.....they designed it to a max hp rating....it does have tolerances....but not that much.

each post that zop gave is true. as well as jig last post.


just something to think about bud

by the way.....i don't think that boat was designed for a short shaft motor that you have on......your splash well will be running close to the water with that low of a transom opening.
its a possible swamp if you are not watching......keep your eyes open for that bud