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Posted: Sat Jan 30, 2010 7:32 am
by foofer b
MattSC wrote:I'm curious as to what Foofer's running for a prop. Most of us with the F-26's are in the range of 14x9 14x10. I've run mine (14x10 cupped) attached to the computer monitoring the engine and I burn around 7.8 gallons at 16kts (2900rpm) 18-19 kts it picks up to around 11gph But, each boat is different. I'm just curious though because his 454 has alot of torque, so he should not have to run it that hard. Maybe he's underpropped. I'm jealous though as I only have a 62 gallon tank and would love to take a trip like that...
I am here, had to reformat to rid myself of a nasty virus and then the site did not notify me I had replies.
Boat came with a 14x10 lh prop, which was too small. Had 2 more inches of pitch added, and it still spun the prop easily. Had a new 14x16 cupped nibral forged and am now over propped. Can only get about 3200 rpm at wot and 21 knots.

Should I have an inch or two of pitch taken out ? If I don't Will it harm my engine if I run at hull speed the majority of the time?
I should probably refine my burn numbers with the new props. I can run six or seven knots at 1200-1400 rpm. The engine is hardly working at hull speed.

Oh and Rodman, it's Foofer B tho you can call me Ray....

Posted: Sat Jan 30, 2010 8:15 am
by mpulsev10
I want to get on board for the bahamas trip, i am in central florida. What dates are you thinking of going ? I probably need a minimum of 3 months planning/preparing my boat. I will pm foofer b and rodman.

Posted: Sat Jan 30, 2010 8:21 am
by mpulsev10
foofer b wrote:Yeah a quick reformat and I am back up and running. My boat burns a round 5-6 gallons per hour at hull speed-approx 7 knots. So it would take 6-7hours at that spped or about 35-40 of the 75 gallon tank. Long drive but very doable. Of course I would only go with at least one other boat, 2-3 would be better. And the extra fuel was just a contingency/exploratory thought. It'd be nice to go 16 knots at 20gph burn.

My boat has 350 gals of fuel capacity. I could probably help accommodate. My family and i already have all of our passports, we went to mexico last summer. But i saw a boat similar to mine sitting in that pretty blue water and man, i wanted it to be mine and be off that huge overcrowed cruise ship.

Posted: Sat Jan 30, 2010 10:13 am
by MattSC
Hi Foofer,
Glad you got your computer back up. If you're only getting 3200 rpm at WOT I would definitely take some pitch out of it you want to be within the specs for your engine, not sure what a 454 should be, but I think it's probably in the ball park of 4200-4400rpm. Just to give you a reference for what I went through after my repower, here's a rundown. First, the specs on my engine are 5.7 Crusader, multi-port fuel injected with 330 HP, my max rpm band is 4800-5200.

I first tried a 14x14 no cup and couldn't get over 3400rpm
14x11 no cup, I reached my rpm band at 5000rpm but the prop was "slipping" and to do 17kts I had to run at 4000rpm. I took a degree of pitch out (they say 1 degree of pitch should be worth about 200rpm) and added a full cup 14x10. I was completely blown away. 3100rpm I can cruise at 17-19kts depending on conditions and at 2900 I can cruise at 16kts burning just under 8gal an hr. WOT is 31kts at 5100 rpm. What I realized was that my boat needed the cup in the prop. Originally I believe they shipped with a Dyna-Jet "super-cupped" prop.

Do you remember what your max rpm was with the 14x12? I'm guessing that you probably could run a 14x11 with a full cup and reach your recommended rpm. Your engine will last much longer and your fuel burn will be alot better than you're getting. As for running at Hull speed, I have always done alot of trolling at low rpm when fishing and haven't had any bad effects

Matt
btw If I was closer to FL I'd be joining you!!

Posted: Sat Jan 30, 2010 11:22 am
by prowlersfish
Foofer B , MattSC is right on target . you need to get the rpm where it should be . Right now you are over loading the engine . You are not only straining the engine you are putting a extra load on your trans and shaft .
The engine may seem happy but it is not. Your HP maybe close to Matt's so the propping maybe close to the same remember you big block weights more so more weight to move and can effect ruining angle


Your hull speed is around 6.5 knots( could be lower not being a displacement hull) you could easily burn twice the fuel at 7.5 knots then at 6 knots , once you go past hull speed fuel burn (HP needed) goes way up until you reach plane where it gets better .

Posted: Sat Jan 30, 2010 11:58 am
by MTP
prowlersfish wrote:What happened to foofer b ? I hope he's not unpset by comments on fuel burn ? :?
I believe he was having computer issues

Posted: Sat Jan 30, 2010 12:07 pm
by prowlersfish
MTP wrote:
prowlersfish wrote:What happened to foofer b ? I hope he's not unpset by comments on fuel burn ? :?
I believe he was having computer issues
Thanks , that what he said , I guess hes ok now posted this am.

Posted: Sat Jan 30, 2010 12:43 pm
by Rodman
I was wondering what prop I have on my F26 so after few pain staking hours of getting the paint off of it that, (Someone painted it.) I see few numbers that does not sense to me. I see one set numbers that are 12 77 looks just like that. Another set that looks like this. 16L 18 anyone have any ideal what those number mean? My engine is a Ford 351. What kinda fuel GPH can I expect with this boat.

Rodman

Posted: Sat Jan 30, 2010 12:55 pm
by prowlersfish
Rodman what gear are you running ? as a 16Lx18 is a large wheel for your boat . A prop shop can check the size of it ( most the time for free) .

Posted: Sat Jan 30, 2010 12:56 pm
by Rodman
prowlersfish wrote:Rodman what gear are you running ? as a 16Lx18 is a large wheel for your boat . A prop shop can check the size of it ( most the time for free) .
I am not sure what Gears are in her. How can I tell?

Posted: Sat Jan 30, 2010 3:14 pm
by prowlersfish
Should beed a plate on the gear box thelling the ratio the number would be sometine like 1:1 / 1.5:1 / 1.91:1 I belive your boat came with 1:1
Its amazine the props I have seen stuck on boats .

Posted: Sat Jan 30, 2010 6:54 pm
by Rodman
I looked today did not see numbers on the plate. I will further investigate more tomorrow.

Posted: Sat Jan 30, 2010 6:56 pm
by Rodman
mpulsev10 wrote:I want to get on board for the bahamas trip, i am in central florida. What dates are you thinking of going ? I probably need a minimum of 3 months planning/preparing my boat. I will pm foofer b and rodman.
We have too see what Islands we are going to go to. Maybe Grand or Bimini Islands.

Posted: Sat Jan 30, 2010 7:10 pm
by prowlersfish
Rodman wrote:I looked today did not see numbers on the plate. I will further investigate more tomorrow.

let me have what info you find and maybe a photo .

Posted: Wed Feb 03, 2010 1:06 am
by cookscomp
Rodman: That prop sounds way too big for your boat. I'm suprised that it will even turn enough to clear your hull. A 351 merc. should use a 71c velvetdrive that is a 1:1 ratio for original equipment I believe. Matt and foofer are closer to what you should be using(14x10). I think that if your prop is too close to your hull the prop wash will cause vibration problems. Maybe someone has done some modifications to your shaft strut and transmission though. If they are that crazy the rest of the boat is suspect as well in my opinion. Most likely though, someone just put the wrong prop on it.