Mercury Revolution 4 project prop.

[Mr. Demeanor]

This prop will be tested on my Fountain Center Console.

I have wanting to do some testing with modifying a Rev4 for some time. I found a great deal on a super clean used 19 Rev4 and grabbed it for the test subject.

PropGods has offered to test a bone stock Rev4 side by side after each mod made for comparison. http://www.thehulltruth.com/images/smilies_imp/thumbsup.gif

Phase 1:
The first modification was to shorten the tube by 1". This will increase bow lift. The job took about 20 minutes with a cut off wheel and then I cleaned it up with an angle grinder. Came out looking like a pro did it if I do say so myself.

I will post performance data as soon as we test this with a stock Rev4 back to back.

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[Mr. Demeanor]

Phase II will be a back cut that Rich at Leading Edge Propeller does to the Rev4.

[baja200merk]

Subscribed

[Toffen]

Hi,

I gained 1,5 mph on wot when cutting down the tube with 30 mm - approx 1,2 inch. More bowlift and less drag too.

Cheeers, Toffen

[arrowwaves]

What do you think about spinning a 23 rev4 on my 250XS on the back of my 24LD Progression? It hit the rev limiter at 5850 and 74mph. tweaked it to @24 now I am just under the limiter at about 5700 and the same 74mph. I would like to hear everyones comments.

[lance]

I hope this post keeps going.

The Rev 4 is my favorite prop so far on a 21’ Checkmate Pulsare. I run a 1.62 Sportmaster but I usually have a heavy load with people and gear. I’m also at high altitude which kills my speed. My best is 74mph at 5900 rpm with 3 people, 3/4 fuel, trolling motor, and extra battery, at 5000’ altitude.

I’ve found the Rev 4’s are usually hard to turn, can be run very high, and have low slip %. My Rev 4 is a 23”, that has been B&B to 22.5” with an additional set of 4 PVS holes. I run with 4 holes open and 4 medium plugs. It runs similar to a Bravo XS or mod’d Bravo I but seems to have a little more lift.

Besides slightly more bow lift and less drag, I’d like to hear if there is any effect on hole shot in cutting the barrel. I think the longer barrel helps reduce slip during acceleration specially when braking over?

[arrowwaves]

Originaly I was running a 1:75 sporty with the built in torque tab and a fat shaft.(prop and gearcase came with the motor with 11 hrs on the used engine) That setup blew out the shift shaft seal every 6-8 weeks. replaced the sporty with a 1:75 fleetmaster. There is really no appreciable difference other than no blown seals. All of the vent plugs are in.

[lance]

Yeah,I had all kinds of problems with my 3.0L Sportmaster leaking. I added the billet driveshaft seal under the water pump and the billet shift rod seal with vent kit. Solved all my problems.

[amityray]

I've been running a 24 trophy plus on my 22 Velocity. I have thought about trying a Rev 4. I'm always looking for more bow lift and was curious if the Rev 4 would do it. Has anyone done a comparison between the two? Also if I'm running a 24 trophy would i need a 24 Rev 4 or do I need to change?

[lance]

Everyone recommended the Trophy for my setup but I didn’t like it. Way too much slip on hole shot and at slow speeds. I also could not run it very high.
I think the Rev 4s come in odd # pitches. I would think a 23” Rev 4 will be similar to, or even turn a little slower, than a 24” trophy.

[arrowwaves]

Yeah,I had all kinds of problems with my 3.0L Sportmaster leaking. I added the billet driveshaft seal under the water pump and the billet shift rod seal with vent kit. Solved all my problems.

I am guessing that the solution is really all about the vent kit. The hot expanded oil needs a place to go. Three seasons with the fishmotor gearcase and no problems. However I am not trying to get every bit of mph gain available anymore. Certainly happy not replacing seals every 8 weeks.

[lance]

I think the vent kit is the way to go. Do a search here on 3.0 Sportmaster gearcase leaks -- lots of posts. Some have success with filling then draining 2-3 ounces out to allow for expansion.

Back to the Rev 4......Mr Demeanor, Any up dates on the Rev 4 mods?

[Mr. Demeanor]

I have not had a chance to run it.

[Mr. Demeanor]

Finally ran the Rev4 with a cut tube back to back with a stock 19 Rev4.

First off, my boat has a lot of natural bow lift and generally does not like bow lifting props. A Mercury Tempest was the absolute worst prop I have run on my boat.

By cutting the tube down, we essentially created a 4 blade Tempest so I am not surprised that it did not run well.

19 pitch Mercury Rev4 w/cut tube: 48mph at 5400rpm
19 pitch Mercury Rev4 stock: 49mph at 5400rpm

Ken was with me for the cut run and not with me for the stock run so that MIGHT account for a couple tenths.

Ken from PropGods was there and provided the stock Rev4. Cruise, mpg, etc were all the same. Holeshot MIGHT have been a little better with the cut prop. Both hooked up extremely well in turns.

I think this prop would work very well on a boat that wants bow lift.

Ken also brought a 19 Mirage plus that we through on just for fine and it ran 49.5mph. My engine is pretty high and the Mirage plus would probably not work well offshore.

In a complete brain fart, I did not bring my Hydromotive QuadIV with.

[Smoking Joe]

Subscribed. I purchased two Rev4 props for my Nova/outboard conversion, 23 and 25 pitch. Will follow with interest.