Yeah, that's one source I've heard of. If you get to know the distinctive paint color the reefer guys used, you can identify one of those surplus engines, even if it's been painted over - the base coat usually shows somewhere.
The Perkins was definitely used in the 26 foot motor whaleboats for a long time. Most Navy ships carried at least one and often more than one. I remember one dark & stormy night about 40 years ago when another vessel needed assistance...
Now-a-days there are tons of Isuzu, Mitsubishi and Kubota engines hitting the market from retired reefers. They would make great power plants for a modest size coastal cruiser.
I repowered my old Albin-25 with a new Isuzu 3CB industrial engine by adapting a seawater pump from a Yanmar and a heat exchanger/expansion tank from an Onan generator. I made a stainless sea water injection elbow in my shop and wired in some gauges. It made a great little unit, around 28 HP.
That boat would do 6.3 knots on 0.4 gph. I came from Portland, Maine to Dighton, Massachusetts, through the Cape Cod Canal and Narragansett Bay on 16 gallons of fuel.
Now I'm looking forward to more cruising adventures with a little more civilized comforts and better sea-keeping ability with the Prairie.
Cappy - have you cruised the Coast of Maine?
J.S.
Al,
Thanks for the pics and my memory was mostly correct. Bilges are a little softer than I had remembered but more importantly the transom is submerged about 8" and the run of the bottom is basically straight. Yes 200hp will plane this hull but at a high angle of attack due to the extremely soft chines.
salormike's boat and yours looks to be about perfectly powered for the hull. When you get a chance post the dia and pitch of the prop. If it's a 3 blade it can probably be optimized unless there's too much blade area. Even then one can cut down the blades and optimize the pitch.
I went back to you're link and from the pics it looks like there's prop clearence. However I assume w the little Perkins the prop is probably too much (big).
Al,
Thanks for the pics and my memory was mostly correct. Bilges are a little softer than I had remembered but more importantly the transom is submerged about 8" and the run of the bottom is basically straight. Yes 200hp will plane this hull but at a high angle of attack due to the extremely soft chines.
salormike's boat and yours looks to be about perfectly powered for the hull. When you get a chance post the dia and pitch of the prop. If it's a 3 blade it can probably be optimized unless there's too much blade area. Even then one can cut down the blades and optimize the pitch.
I went back to you're link and from the pics it looks like there's prop clearence. However I assume w the little Perkins the prop is probably too much (big).
For your boat 22" dia is too much prop w the 2-1 gear. I'd cut it down as a knee jerk reaction. Going to a lower gear would be better but props are cheaper than gears. But w either the cut down prop or a different gear ratio you've got plenty of power
Yes I'd like to hear TAD's take on it too.
Sailormike
I'm not so much looking for information as looking for folks who are interested in setting up cruises. Are you still in the area, perhaps?
Cheers!
J.S.
Willow- We have a 27 foot Marben trawler which has a 10 foot beam at the widest point although the stern tapers to 9 foot beam across the deck. We draw 3 feet and consider our hull F/D (Eric-) As I review your post I agree to the 'Hobby Horse' into head seas. We recently pulled a Perkins 4-154 (58 HP) out and installed a running Perkins 4-236 in its place.(85HP)
The 154 had a 3;1 and we changed to a 2;1 with the 236 and kept the same wheel. We are honorably over wheeled by forum standards. Our top RPM is 2000 on a 2800 rated RPM scale. Now Willow, we should have a lower hull speed than you yet when we use the Vicprop formula
:Vicprop - Propeller Calculator
we have and do cruise, at the hull speed of 6.9 knots the formula produces. We run at 1400 RPM so we still have a safe margin of 600 RPM which as you indicate, is the best setting as anymore throttle just creates water displacement, noise, and smoke, very little improvement in speed. We consume 1.3 gallons per hour. We think we are fine with this over wheel results.
Okay- Now here is an area to compare. We have a limited fuel capacity of 90 gallons, 48 gallons of water. The engine/gear weight is 1500#. We have little in the area of anchor chain, 25 feet, so that is not a factor by itself.
Due to the "Hobby Horse" effect combined with a horrid snap roll in the for mentioned weight factors, we were alarmed at the motion of the boat, unsafe not but very uncomfortable would be fair.
As a result of many suggestions from our Forum members, all in good intent and welcome, we were fortunate to local locally, 50# lead ingots. We purchased in total 1300# and installed them thus, We added one 50# directly to the chain locker floor. At the junction of the v-berth there is a floor locker cabin, we added one 50# to the floor of that locker. Moving back we installed
6- 50# ingots above the keel in a existing alley. Under the engine/gear we placed 4-50# ingots. Along side the engine bed-port side, we placed 6-50# ingots favoring aft abeam the reduction gear. We placed 4-50# ingots on the Starboard side mid ship of the engine (Aft of this weight is located the 11 gallon hot water tank which offsets. The remaining ingots were placed in the lazeret evenly aside the rudder stock.
The outcome is a perfectly balanced boat!!! We cut the Hobby Horse down to nil, the boat cuts more than lifts. Following seas affect us sitll yet at a lessor degree, the yawl is slowed way down. We can ride beam seas in a fashion where the boat rides up, the wave or swell moves UNDER, the boat remains in a vertical stance, any roll is gentle and slow.
All of this weight on top of the as built of 1500# of lead in the keel, and the boat burns not enough additional fuel to make a noticeable difference.
Here is a site of a sister boat that we almost purchased:
1978 Marben Flybridge Trawler Pilothouse Pocket Cruiser Title
Would you be kind enough to view the photos and comment as to how close all of this is to your boat/conditions? Note the fuel and such in this boat and understand the weight difference between our boat and this one due to tankage alone.
Long response, sorry
Al-Ketchikan
Willow,
I'm propped at rated rpm of 3000 and run at 2300. When I run up to 2500 there is considerably more noise and a bit more vib too. 22-2300 seems the sweet spot.
The prop guy was a good find.
Small world-I've done business with Toup's since 1971-know their stuff-FYI I have a '83 30' Atlantic (updated Prairie 29) with a 165 Volvo swinging a 18 dia 15 pitch 4 blade-WOT 2800 (over propped, I know) but reach hull speed at 16 to 1800 rpm-7 knts-very smooth and quite-less than 2 gals per hour.Okay... Just got off phone with Toups Prop Svs in Abbeyville, La.
After researching boat & 4-108 they advised that I am extremely under propped. Suggested ideally to move up to 20" wheel. But advised that as I already own both a 3 & 4 blade 18" wheels, simply repitch the 4-Blade to 14" of pitch or the 3-blade to 15" of pitch and you are where you need to be. Said as I'm not trying to push any harder than hull speed, should not be much additional load on engine. As long I'm not black smoking, I should see the results I'm looking for at 25-2600 rpm. Stated he has experience with 'those little Perkins' and 25-26 is the sweet spot.
Thanks to all.
Small world-I've done business with Toup's since 1971-know their stuff-FYI I have a '83 30' Atlantic (updated Prairie 29) with a 165 Volvo swinging a 18 dia 15 pitch 4 blade-WOT 2800 (over propped, I know) but reach hull speed at 16 to 1800 rpm-7 knts-very smooth and quite-less than 2 gals per hour.