2800SX Outboard Restoration Begins!!!

[demag67]

i knew I read it somewhere. http://www.mercuryracing.com/blog/prop-school-part-5-blade-efficiency/

 

[JUPITER PULSARE]

i knew I read it somewhere. http://www.mercuryracing.com/blog/prop-school-part-5-blade-efficiency/

If you read the article, from what I can see they are talking "Cat" applications. As I stated earlier, most of the V bottoms we set up years ago handled better with the props turning outward but were not as fast as turning the props inward...but again, every hull may react different based upon many factors; deadrise, center line difference, setback, prop design, V hull vs Cat hull, etc. etc. The only true way to find out is to go through the labor of swapping everything out and run the same set of props....

 

[demag67]

I'm no expert (I did stay at a Holiday Inn Express one time...) but my boat ran very loose at WOT when the props were turned out. Felt like the stern was jumping around at speed. I didn't like it. Also, handling around the dock was worse.

2ton, it will be interesting to see what you find.

that commercial must be true.

I called a guy I talked to before that sets up offshore race boats and asked him what the total theory is on this subject. by how he explained it to me is thrust comes from where the prop meets clean water, in our case on a vee hull, clean water is on the outside of the lower units, since this is the shallow part of the hull, inside is where the prop is actually surfacing due to this being the deep part of our hull. so outwards the prop blade is going down when it is going through the clean water giving upward thrust, when it is turned in it is going through clean water going up, this holds the stern in the water and allows the boat to lift the bow. I forget which way he said was worse when moving around docks.

 

[JUPITER PULSARE]

We'll know the in vs out question by this weekend. After having motor problems last night I'm digging into my starboard motor today (possible bad switch pack or stator) and I'm swapping my lower units to spin the props in. I'm sure I'll achieve more stern lift and top end speed. I'm trying to get the boat ready for this Friday at River Ranch 2013!!

 

[JUPITER PULSARE]

Lower units are swapped to spin the props in. Shift cables are moved to the proper positions so forward and reverse work correctly!! New switch boxes are installed in the starboard motor. This morning we are de-carboning both motors with PowerTune, installing new plugs, Bob's high performance wires on the starboard motor, and hopefully water test the boat late this afternoon. If all goes well I'll be running up to River Ranch for friday!!! Hopfully...I may pickup a few miles an hour...would love to get to 75MPH!!!!

 

[2tonchevy]

Lower units are swapped to spin the props in. Shift cables are moved to the proper positions so forward and reverse work correctly!! New switch boxes are installed in the starboard motor. This morning we are de-carboning both motors with PowerTune, installing new plugs, Bob's high performance wires on the starboard motor, and hopefully water test the boat late this afternoon. If all goes well I'll be running up to River Ranch for friday!!! Hopfully...I may pickup a few miles an hour...would love to get to 75MPH!!!!

hell yeah!

KEEP US POSTED!!

75 MPH OR BUST!!!

 

[JUPITER PULSARE]

The gremlins continue to screw with my starboard motor! After replacing both switch boxes, new plugs, new wires, and a can of PowerTune she's still off on power. I've gone through the carburators a few months ago but they're getting pulled to look at again..I've also got my buddy checking the timing, coils and stator today...Unfortunately, I won't be making RiverRanch today!!! The good news is that the motor has never quite been up to snuff (I rigged the boat, fired up both motors after they've sat for years, and have been playing with the boat ever since without giving either motor any "Love") and the boat still achieved 71.11mph....so, if I can get my starboard motor running as strong as the port motor...and with my gear cases spinning in...I've got to be faster than before!!!!!

 

[JUPITER PULSARE]

Getting closer...by the time I'm finished both 2.4L motors will be screaming! After installing new switch boxes, plugs, hi-po plug wires, setting timing, and treating the starboard motor with PowerTune we had her spinning 6500rpm yesterday...but she'll occasionally fall off?? Gonna check the stator and harness on the starboard motor today. The starboard motor is now running 500 rpm more than the port motor!!! In the process of checking the port motor (new hi-po wires, plugs, timing & powertune)we found a pin hole in the fuel pump diaphram so we put a new fuel pump in the port motor...under load it still doesn't pull as strong as the starboard motor so we may change to the newer style fuel pump using the block adapter. Both motors will be going on the dyno today at Nicks Creative Marine in Riviera beach. I have the best guys (good friends that I've known and have raced for years) breathing new life into my old 2.4's. The goal is to get both motors spinning 6500 rpm and 75+mph!!!

 

[JUPITER PULSARE]

Test #1 after work completed.

Left work last night at 6:10...rushed to the shop to pickup the boat...rushed home to pickup the wife...and rushed to the boat ramp to run the boat just before dark! Both motors now idle great without stalling...and believe me, trying to dock a 28' twin engine boat when the motors keep stalling (and there's wind, currents and other boats to damage) will put gray hair on your head!! So with both motors purring like tigers we idled past Jupiter Lighthouse to the "slow" speed zone where I cracked the throttles! The boat instantly JUMPED out of the hole and the excelleration was really strong. As I trimmed the motors up and leveled my trim tabs the boat really began to fly and felt much "lighter" with the props spinning in. I could actually feel the boat on the pad (like driving a giant Pulsare) as I past 65 mph. We were heading into a stiff north wind at about 15-20mph in protected flat water and 80+ degrees with about 75 gallons of gas...and getting DARK...my GPS flashed 70.44 mph before I had to back out due to a "no wake" zone coming up quick. The boat had NO more bounce and drove perfectly level with the props spinning in. I wish I had more daylight to play...but in the dark, channel markers that you can't see come up fast and I surely didn't want to push my luck. So to sum things up, here's my first impressions and data:

A) Port motor has 135lbs accross all 6 cylinders. Reflected 6000rpm.
B) Starboard motor has 118-125 accross all 6 cylinders. Reflected 6200rpm.
C) Boat runs better with the props spinning in...spinning in pushes the stern up allowing the boat to run with less drag and hull in the water. With the stern pushing up and trimming the motors up I can get alot more total lift and overall better seat of the pants feel.
D) Turning the props in along with giving both motors some much overdue "love" alleviated the mid speed bounce that I was getting. Now the boat just flys level accross the water at all speeds!
E) I haven't achieved my goal of 75mph...yet. I still have to replace the reeds and send my DAH chopper 26 props out and have them worked to try and achieve 6500 rpm. Right now the boat is a solid upper 60's/low 70's mph boat. Not to shabby for stock 200hp fishing motors!!!

 

[JT Patroni]

Well deserved results after much hard work.

Keep it up!

 

[DropTop5.0]

Not to shabby for stock 200hp fishing motors!!!

I think that it pretty darn impressive!

 

[2tonchevy]

sweet!

back on the water!

so how do yo think the top speed will compare with props turning in as it sits right now?? how bout handling??

interesting that your top speed was lower turning in (i know you said you had to back out so it may not be a apples to apples comparison.) ive always heard turning in would be good for several mph more but ill handling effects.

do you think turning in will best your 71.1 you got with the props turning out???

im glad yo got rid of the hop too man...ive rode in boats that did that and its annoying as hell.

im hoping i can break 70 also! im running 2.0 lowers with 26 choppers so my rpms should be much higher....

i also have a set of 26 hydromotive 4 blades im gnna try...

 

[JUPITER PULSARE]

sweet!

back on the water!

so how do yo think the top speed will compare with props turning in as it sits right now?? how bout handling??

interesting that your top speed was lower turning in (i know you said you had to back out so it may not be a apples to apples comparison.) ive always heard turning in would be good for several mph more but ill handling effects.

do you think turning in will best your 71.1 you got with the props turning out???

im glad yo got rid of the hop too man...ive rode in boats that did that and its annoying as hell.

im hoping i can break 70 also! im running 2.0 lowers with 26 choppers so my rpms should be much higher....

i also have a set of 26 hydromotive 4 blades im gnna try...

Max, I really didn't have the daylight to try and squeeze every mph out of the boat last night...it was getting pretty dark and my wife was on board. I think with a bit more seat time and tinkering between the trim and tabs I might have more mph in it. The overall feeling of the boat felt lighter at speed. I could actually feel the boat sliding around on the pad a bit..and I'm sure if I trimmed up higher I probably could've gotton the boat to chine walk!!! If I can make it chine walk and learn to balance on the pad the boat should be faster! Time will tell. The overall performance of my 2.4's was most impressive with all the "love" they've received the past few days. They idled nicely, popped the boat out of the hole instantly, pulled really strong, had great mid range snap, and turned 6000 rpm with the DAH 26 choppers. The reality is the boat will run upper 60's all day long and with some driver input top 70 MPH. My next step may be to try 20" mid sections to raise my drive height....

 

[2tonchevy]

Max, I really didn't have the daylight to try and squeeze every mph out of the boat last night...it was getting pretty dark and my wife was on board. I think with a bit more seat time and tinkering between the trim and tabs I might have more mph in it. The overall feeling of the boat felt lighter at speed. I could actually feel the boat sliding around on the pad a bit..and I'm sure if I trimmed up higher I probably could've gotton the boat to chine walk!!! If I can make it chine walk and learn to balance on the pad the boat should be faster! Time will tell. The overall performance of my 2.4's was most impressive with all the "love" they've received the past few days. They idled nicely, popped the boat out of the hole instantly, pulled really strong, had great mid range snap, and turned 6000 rpm with the DAH 26 choppers. The reality is the boat will run upper 60's all day long and with some driver input top 70 MPH. My next step may be to try 20" mid sections to raise my drive height....

thats great man. glad your gettin it dialed in.

i can def say that our hulls share the "loose" at speed characteristic. my boat feels more like a cat than a V when you are trimmed hign and runnin in a good shop. lol

so tell me: did you find the overall handling characteristics of more predictable and stable with the props turning out?? i know you havnt really had a chance to find out whats what yet...but keep me informed....im curious

i have heard from several people that a 4 blade will also give a much more stable ride even when turned in.

i ask only because i honestly would turn my props out to get a bit more stability and cut down on the driver input a bit if the speeds would remain within a couple mph.....witch seems to be the case. you are finding out the same thing i did...this boat takes skill to drive if you wanna go fast in the rough....its not just a mash the throttle and go type of rig.

 

[SCT]

Jup. I agree....my boat felt like a big pulsare when it was up on the pad vs an offshore IO. Can't wait to see your final top speed.

 

[2tonchevy]

Jup. I agree....my boat felt like a big pulsare when it was up on the pad vs an offshore IO. Can't wait to see your final top speed.

hey sct...

how many mph difference did you see when turning in vs. turning out???
if i recall you liked turning out better......

 

[SCT]

2ton, I really don't remember much of a speed difference. I tried out one time and did not like it. Felt like the back of the boat was jumping around. In was much better handling in my opinion.

 

[JUPITER PULSARE]

2nd time out with the new setup last sunday. The boat felt great...strong out of the hole, impressive midrange and right at 70mph GPS with 96 gallons of gas (rougly 600lbs!) on board, 3 adults, and two coolers! 85 degree temperature @ sea level in flat sticky water..The beast definitly feels better with the props spinning in..with a neutral trim the nose drops and the boat takes a nice level set and just eats up water!!

 

[JUPITER PULSARE]

I got a little bored at work this morning..so I plugged my speed data into Mercury's Prop Slip Calculator. Based upon my 26 pitch DAH choppers, 1.87 gear ratio, rpm @ 6300 and GPS speed of 71.11: I'm showing 14% prop slip which seems to be within reason for 3 blade choppers. I think there's a little room for improvement..I may have to hunt down some
4 blade choppers and raise my lower units (swap to 20" legs)!!

http://www.mercuryracing.com/propellers/propslipcalculator.php

 

[Instigator]

Good stuff.

I'm still struggling w/set up on this Sonic but the old one was happiest w/Choppers too. It's best was 6400 @ 80 but that worked out to a staggering 8% slip which I've not duplicated on anything.
Normally 10% is within reason on a rig like yours w/those wheels if all else is perfect.
I have heard other people "claim" better but never seen it backed up.
A calculator doesn't lie. May cost you a ton of money though.

Change the slip # in your calculator to 10 and see what happens

Good luck on the 4 blades. W/o having them built new, I've only (ever) seen one set and they're on their way here.
If we ever cross paths you're welcome to try them.
Matter of fact, maybe swap help testing?? I don't have anyone close that's knowing/willing.
I have a set of 27" Mirages that should be great on that boat too. For sale.
$400. to you if interested.