Reply
 
Thread Tools Search this Thread Display Modes
 
Old 05-22-2020, 11:48 AM   #1
Veteran Member
 
City: Chula Vista, Ca
Country: USA
Vessel Name: Curly Sez Wow
Vessel Model: Gulf Star
Join Date: Oct 2014
Posts: 72
fuel usage

We have a 1978 Gulf Star 44' with twin original Perkins 254's with approx. 1,500 hours on each. With main and aux. fuel tank we can carry over 700 gals. of diesel fuel. We measure fuel usage by dip stick. On a return from Ensenada to San Diego at an average of about 9 knots it appears we used about 3 gallons per hour running both engines. Is this possible? When I tell people this they look at me like I'm nuts, which I may be but that is the reading I get and it's been about the same on other, shorter, voyages.
__________________
Advertisement

henryj2 is offline   Reply With Quote
Old 05-22-2020, 12:34 PM   #2
Technical Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Country: USA
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 5,651
At 9kts I think 3gph is low. Probably a bit more than that. I would guess 4ph. But Gulfstream are very slick hydrodynamic hulls, so maybe it is 3.

Also Perkins made a 6-354 and a 4-236, so probably not a 254.
__________________

Ski in NC is offline   Reply With Quote
Old 05-22-2020, 12:43 PM   #3
Guru
 
Nomad Willy's Avatar
 
City: Concrete Washington State
Country: USA
Vessel Name: Willy
Vessel Model: Willard Nomad 30'
Join Date: Oct 2007
Posts: 16,624
If your boat takes 60hp to go 9 knots it's possible.
But more likely w a FD hull. HaHa maybe it is.
Like many you may be counting time running the clock and being at less that cruise throttle. The clock goes at one speed. Little periods of time spent stopping or slowing, warming up the engines ect ect will give you "wonderful" numbers. The time adds up more than most of us think.
Does your stern look more like a Bayliner trailerboat or a sailboat?

Ski didn't Perkins make a 154 or nearly so?
__________________
Eric

North Western Washington State USA
Nomad Willy is offline   Reply With Quote
Old 05-22-2020, 02:20 PM   #4
Technical Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Country: USA
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 5,651
Yep, they did make a 154. Maybe that is it.
Ski in NC is offline   Reply With Quote
Old 05-22-2020, 02:33 PM   #5
Guru
 
Nomad Willy's Avatar
 
City: Concrete Washington State
Country: USA
Vessel Name: Willy
Vessel Model: Willard Nomad 30'
Join Date: Oct 2007
Posts: 16,624
Ski,
And if it was the same hull form (approx) as the Gulf Star 36 .....
Could easily do 1.5 gph oer engine. But more likely if he was say’in 8 knots.
__________________
Eric

North Western Washington State USA
Nomad Willy is offline   Reply With Quote
Old 05-22-2020, 06:00 PM   #6
Guru
 
High Wire's Avatar
 
City: Cape May, NJ and Englewood, FL
Country: USA
Vessel Name: Irish Lady
Join Date: Dec 2007
Posts: 3,193
4 or 6 cyl?
__________________
Archie
1984 Monk 36 Hull #46
Currently in New Jersey.
High Wire is offline   Reply With Quote
Old 05-22-2020, 06:19 PM   #7
Guru
 
City: Carefree, Arizona
Country: usa
Vessel Name: sunchaser V
Vessel Model: DeFever 48
Join Date: Apr 2008
Posts: 8,556
Henry
Are your tanks cubes or conform to hull sides? If each inch of drawdown is a different volume, is your dipstick calibrated? Also 40 hours per year of use is interesting and less than 150 gallons per year on average.

Nice boat and great efficiency, my questions aside.
sunchaser is offline   Reply With Quote
Old 05-22-2020, 07:26 PM   #8
Veteran Member
 
City: Chula Vista, Ca
Country: USA
Vessel Name: Curly Sez Wow
Vessel Model: Gulf Star
Join Date: Oct 2014
Posts: 72
Fuel usage

Thank you to those who replied.
The answers to the various questions posed are:
1. It is a 354 turbocharged. Would like to say it was a typo but more of a senior moment, I fear.
2. 6 cylinder.
3. Main tank conforms to hull shape. We also have an axillary tank under the aft deck that was originally (we believe) set up for water but was switched to fuel somewhere prior to our purchase.
4. Nomad Willy could also be correct, sloppy accounting for time under full power could account for part of what seems to me such stingy (although wonderful) fuel usage.
5. We have seen several Gulf Star sail boats with the exact, or nearly so, hull and have been told that was one of designers ideas, to make a hull that could serve either sail or power.
henryj2 is offline   Reply With Quote
Old 05-22-2020, 07:48 PM   #9
Guru
 
tiltrider1's Avatar
 
City: Seattle
Country: USA
Vessel Name: AZZURRA
Vessel Model: Ocean Alexander 54
Join Date: Aug 2017
Posts: 1,789
44’ hulls don’t do 9 knots with out climbing the bow wave. I would believe those numbers at 8 knots but not at 9. I’m guessing there is some inaccuracies in the data. How did you measure fuel usage? How did you measure speed? How did you measure hours?
tiltrider1 is offline   Reply With Quote
Old 05-22-2020, 07:56 PM   #10
Veteran Member
 
City: Chula Vista, Ca
Country: USA
Vessel Name: Curly Sez Wow
Vessel Model: Gulf Star
Join Date: Oct 2014
Posts: 72
Thanks for the comment:
Speed: garmin
Usage: as stated, dip stick
hours: clock
Could well have been 8 knots, note I said "approx. 9 knots" I agree could well have been only 8 or right at it on average. Bash from Ensenada to SD pretty rough and bouncy.
henryj2 is offline   Reply With Quote
Old 05-22-2020, 11:41 PM   #11
Guru
 
tiltrider1's Avatar
 
City: Seattle
Country: USA
Vessel Name: AZZURRA
Vessel Model: Ocean Alexander 54
Join Date: Aug 2017
Posts: 1,789
Garmin sounds like GPS speed over ground. There are several things that could distort this number. Dip stick is not very accurate. Always Refilling the tanks to a fixed point tells exactly how much fuel was used. The clock doesn’t tell me much. I’m guessing you didn’t use the engine Hobbs meter. The clock on the wall is usually a guess as we rarely look at the clock when we start and stop the engines. It takes a bit of work, a lot of consistency And multiple attempts to zero in on a boats true fuel consumption.
tiltrider1 is offline   Reply With Quote
Old 05-23-2020, 07:22 AM   #12
FF
Guru
 
FF's Avatar
 
Join Date: Oct 2007
Posts: 20,498
For boats used inland the usual hassle is many waterways are statute miles , not nautical miles.


5K = 6 Mph so its Ez to confuse 7+K as 9mph.
__________________

FF is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 02:37 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012
×