Quintrex repower? Any Aussies out there?

General boating discussion
Livliner
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Joined: Sat Jan 12, 2019 7:18 am
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Quintrex repower? Any Aussies out there?

#1

Post by Livliner »

Hello all, new to the forum glad I found it.
Time to repower my 14 ft Quintrex Dory 139. New in 2000 my boat has been powered by a
18hp Tohatsu 4 stroke tiller 124lbs.. Rating plate says it can take a40hp. Thinking this rating was four a 2 stroke which is lighter. Although underpowered a bit this 18hp has worked out well because my launch to fish range is only 1-2 miles. I also have a DIY 40 gal live baitwell sitting mid ship (300 lbs). The boat squats a bit with battery, gas and tiller operation aft, but no issues, has worked out well. Want to repower with 30hp 4 stroke tiller 160-180 lbs. Think it can handle 50lbs more motor weight? Should I stay with 18 or 20 hp. Don't want ro relocate battery and gas to distibute weight. Setup works great but want more power and range. Chime in Quintrex owners, any Aussies out there?
kmorin
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Re: Quintrex repower? Any Aussies out there?

#2

Post by kmorin »

Livliner, we have to suffer through the post without pictures? AH..... that's hard - most of us in the States don't know the Quintrex skiffs- but we'd all like too!

It time allows, post up your boat so we can see her an enjoy considering what we'd individually do to re-power that skiff? is she like this one? http://www.ctfisherman.com/ubbthreads/u ... _Dory_Wide

Cheers,
Kevin Morin
Kenai, AK USA
kmorin
Livliner
Posts: 4
Joined: Sat Jan 12, 2019 7:18 am
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Re: Quintrex repower? Any Aussies out there?

#3

Post by Livliner »

IMG_0206.JPG
IMG_0206.JPG (149.97 KiB) Viewed 4942 times
Yes the picture in the link you provided is the same as my boat. However mine is a tiller not a console model. The boat is made in Austalia but in 2001 they had a couple of dealers in the US. I purchased mine in Middletown, CT. I don't have many pics of my boat but here is one I will attempt to post
kmorin
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Re: Quintrex repower? Any Aussies out there?

#4

Post by kmorin »

Livliner, first to address a bit of "adspeak" in the misnaming of the shape of the skiff you show- that's not a dory! I know that lots of people use different terms in different locations and worse; the manufacturers use a host of miss-used terms about boats..... but that's a roll formed skiff.

It's got more than enough beam to hold a 30 -40 or they couldn't list it on the nomenclature plate; so you'd be fine with a 40 back there. It will squat a good deal from that much wt on the transom, and it would part of any good quality re-fit to move the battery, fuel and other wt forward.... but with those nice tall sides and fairly wide stern (at the chine) I'd say she'll carry more wt and be OK.

The reason to move the fuel, batteries and other wt.s is to give yourself the most 'flat' trim you can due to the increased wt. This is only critical if you have this skiff where she's taking a chop by the transom (?) or "wind under her skirts" as has been said in the past. In that case, where all the main wt.s are at or near the transom- you're not giving the hull as much chance to use her buoyancy to pitch evenly about the swell from astern.

It seems curious to me that you'd consider adding a double hp and wt change... and not see that the very well drawn little hull needs to have the new wt balanced to allow her to continue being the well manner little skiff she appears? By overburdening her by the stern- you upset her balance and she won't/can't pitch up her stern to lift the new wt (with the fuel and batteries) in a following sea/chop/stern wave....

What about leaving the fuel, unless you increase the tank size, and just moving the battery? a 10lb wt moved forward 5' would make some serious compensation for an added 50lb at the stern. How about just adding a full cooler - 25lb at the bow would sure go along way to trim her back flat!

I've not seen this brand of manufactured boat before, but I like the rolled sides' 'planked steps'; they simulate a planked skiff and the steps in the rolled aluminum will bring about some very serious rigidity from the extremely thin material of her scantlings.

Just a few cents of opinion about the image and your original questions.

Cheers,
Kevin Morin
Kenai, AK
kmorin
Livliner
Posts: 4
Joined: Sat Jan 12, 2019 7:18 am
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Re: Quintrex repower? Any Aussies out there?

#5

Post by Livliner »

Thanks Kmorin for your response. Perhaps I'm overthinking this. i think upgrading to a 30hp 4 stroke from 18hp will be Ok. My 30-40 gal round baitwell that I have just forward of midship allows me to control weight distribution. Solo I fill it 1/3 brings the bow down etc. Fill and drain on the go as needed for bait and weight. Although I fish solo most of the time,when I have a buddy along with 200+ lb of water in the baitwell speed becomes very deficient. Will I get more speed with a doubling of HP or will the added 50lbs of motor weight cancel that out.? Not expecting a doubling of speed but a few more knots of forward momentum would be nice. If not I will go,with a 20hp rather than 30hp. Surely others have dealt with this issue. Your mention of skiff vs dory, manufacturer graphics on side the labeled the a boat dory.
kmorin
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Re: Quintrex repower? Any Aussies out there?

#6

Post by kmorin »

Livliner wrote: Sun Jan 13, 2019 10:08 am Will I get more speed with a doubling of HP or will the added 50lbs of motor weight cancel that out.?
no you'll get more speed, but not double.... the 50lbs is well within your bait tank/well high to low so not going to make the difference to cancel the added horse/push power.
Livliner wrote: Sun Jan 13, 2019 10:08 am Not expecting a doubling of speed but a few more knots of forward momentum would be nice.
you'll get that and probably more, meaning 4-8 depending on loading and trim. If you can get the wt forward and add the horses, you'll run much faster while flat/pitched level by the bow. Light conditions you may get more than 10 knots? as the hp/wt ratio is getting quite a boost but the all-up displacement and Beam/Length ratio is staying fixed.
Livliner wrote: Sun Jan 13, 2019 10:08 am your mention of skiff vs dory, manufacturer graphics on side the labeled the a boat dory.
yes, as noted the terms for hull shapes are still widely divergent- even if American authors have pretty well discussed the terms - exhaustively- in books published many decades past! I know people, have known them my entire life, who use the term dory for a skiff shape, and have told me I don't speak English as long as we've associated! But a Dory shape "returns the chine and sheer by 1/2 their Master section in the run aft to the transom, viewed in Plan View." A skiff shape has little or no "return of the chine and sheer in Plan View".

http://www.raysriverdories.com/ here's a page where the builder differentiates one shape from the other.

Cheers,
Kevin Morin
Kenai, AK
kmorin
Livliner
Posts: 4
Joined: Sat Jan 12, 2019 7:18 am
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Re: Quintrex repower? Any Aussies out there?

#7

Post by Livliner »

Thanks, kmorin, for your detailed responses. I think upgrading to a 30hp from my current 18hp will be a good fit for the small boat. As you have suggested, my 30-40 gal.live baitwell that is located forward will help compensate for the added motor weight aft.
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