09-07-2011 08:01 - edited 09-07-2011 09:10
Just repowered my 2007 Tracker Grizzly 1754 SC with a 75 hp E-TEC w/ 13.5x17 Viper prop. Previous power was a Merc 4-stroke 25hp engine.
Load 1 person (190lbs), 10 gals gas, safety gear (edit: trolling motor and battery up front.)
Time to plane..about 2 seconds.
WOT 5000 rpm, 41 mph
4000 rpm, 30 mph
3500 rpm, 28 mph
3200 rpm, 25 mph
Fuel usage ~7.5 mpg over 20 mile course, mixed throttle settings but mostly at about 3200 rpm and 25 mph with some short runs at WOT.
Bilge outlet on right side is above waterline at rest.
If you can, give a 15" Rogue prop a try and see if it is more efficient at cruise speeds and if it performs better with several people in the boat, along with a full gas tank, and more gear aboard. Your rpm is on the low side with such a light load.
"There is never just one thing wrong with a boat";
-- Travis McGee, main character in a book series by John D. McDonald
The factory recommends that a properly trained technician service your Johnson or Evinrude outboard motor. Should you elect to perform repairs yourself, use caution, common sense, and observe safety procedures in the vicinity of flammable liquids, around moving parts, near high-temperature components, and working with electrical or ignition systems.
The information offered here is only general in nature and should not be construed as complete factory approved procedures, techniques, or specifications. Always use the proper service manual for your motor, up-to-date service literature, the correct tools, and have an understanding of how to proceed with troubleshooting and repair methods. If you are unsure or uncomfortable with a procedure, a situation, or a technique, enlist the services of a factory trained technician.
During the test run, it was windy and choppy. Both the run out and the run back had headwinds and strong crosswinds due to weather approaching. RPM's looked good to me. However, I would expect a little better in calm water with no wind. Speed was reported by GPS not a water wheel. It was a light load, but I neglected to mention the trolling motor and big battery up front (~80-90 lbs motor and batt).
This weekend I should have an opportunity to test the setup with a normal load on a typical mission profile. Basically that includes myself, another person, a 150qt ice chest, 5 gal bait bucket, and rods. I figure the typical fishing trip is about 300 lbs more than my test run yesterday. Typical distance on water is 25-30 statute miles one way for a back country trip.
Photos when I can get the time to upload them.
Just did a fishing trip from Flamingo, Florida out to Shark River and back yesterday with the e-tec powered Grizzly.
Load out was 2 people (350 lbs), 150qt ice chest (~50lbs), trolling motor and battery (80 lbs), safety gear (~20 lbs), fishing tackle, rods and food etc (~15 lbs). Fuel load was 13 gallons.
Total distance was 49.1 sm. Used 6.6 gal of gas. Typical power setting was 3000-3300 RPM and cruise speed was about 23-25 smph. Average fuel economy was 7.4 smpg.