Merc 200hp on a 1974 Tsunami 20' - Propping Performace

[Fr. Frank]

16"p 4b PowerTech is too much pitch. You'll still not be able to achieve 5800 rpms WOT.
Figure on getting an effective 1.5" to 2" extra pitch from the 4th blade. So you're still in the same range as a 17.5-18" 3-blade.

I ran a custom 3b Powertech 15.25"Dx16.5"P on a Mercury 200 on the back of my 20' Seafari. Max RPM was 6050 at about 53 mph lightly loaded, and 5800 rpms WOT at max load. (I also had a nose-cone and low-water pickup with a manual jack plate)

You want to propped so as to be able to achieve Max of Max at Max.
That's maximum end of the recommended maximum rpm range while at maximum recommended loading. It's really a good idea...

[Bigshrimpin]

I am assuming you have a carb 1993 mercury 200.

Page 191 shows jet chart. =>

http://www.hedges-uk.com/boat/Merc/o...0Magnum%20.pdf


3B-34 - FUEL SYSTEMS
90-824052R2 SEPTEMBER 1997
High Altitude Jet Chart
Factory installed main fuel jets are normally adequate for proper performance up to approximately 5000 feet
(1524m) above sea level. Between 2000 feet (609.6m) and 5000 feet (1524m) the reduction of the main fuel jet(s)
may result in improved performance and fuel economy. Above 5000 feet, however, it is recommended that main
jet size be reduced as shown per 1000 feet (304.8m) in the following chart.

[GameOnSalmon]

Originally Posted by Fr. Frank

16"p 4b PowerTech is too much pitch. You'll still not be able to achieve 5800 rpms WOT.
Figure on getting an effective 1.5" to 2" extra pitch from the 4th blade. So you're still in the same range as a 17.5-18" 3-blade.

I ran a custom 3b Powertech 15.25"Dx16.5"P on a Mercury 200 on the back of my 20' Seafari. Max RPM was 6050 at about 53 mph lightly loaded, and 5800 rpms WOT at max load. (I also had a nose-cone and low-water pickup with a manual jack plate)

You want to propped so as to be able to achieve Max of Max at Max.
That's maximum end of the recommended maximum rpm range while at maximum recommended loading. It's really a good idea...

Father... Thank you for the Input... So are you saying i need to go as low as a 15p on a 4 blade to hit Max of Max of Max? I am not too shabby and getting The Set Up...and I am picky kind of like bushwhacker.. Been Jacking IN 1/4" Increments Now i can pull 5150 and Its up high but the Water Pressure Gauge which i installed is still good.

If i decide to run a 3 blade I think i am Going to Roll with the Enertia in 17p. Which i should be able to Spin at 5800 Here where I am at and close to 6200 on the Coast. Thoughts? I would love to have the jack Plate Marked to Run the Enertia here at altitude and then mark and test if for the Powertech when on the Columbia river and the Salt water...

Thanks for your Input Much Appreciated.
Robert

Originally Posted by Bigshrimpin

I am assuming you have a carb 1993 mercury 200.

Page 191 shows jet chart. =>

http://www.hedges-uk.com/boat/Merc/o...0Magnum%20.pdf


3B-34 - FUEL SYSTEMS
90-824052R2 SEPTEMBER 1997
High Altitude Jet Chart
Factory installed main fuel jets are normally adequate for proper performance up to approximately 5000 feet
(1524m) above sea level. Between 2000 feet (609.6m) and 5000 feet (1524m) the reduction of the main fuel jet(s)
may result in improved performance and fuel economy. Above 5000 feet, however, it is recommended that main
jet size be reduced as shown per 1000 feet (304.8m) in the following chart.

Tim... Sweet, I tried to find those Charts and even called a couple of Dealers. You would think i am speaking Chinese to these guys... I am like Good God your Mechanics work on this Stuff every day... Can you have someone check the Shop manual? These are Dealers who I buy a lot of stuff from... but I will Not be buying from in the Future... When i get the ... UMMM... NO.. We are not your Personal Mechanic... Look it up on the Internet. The guy was a total Ass... Thanks for Putting this up for me I aprpeciate it.

Still working on the Set Up... I have my jack Plate all the way up... and Still think I can move the Engine up a couple of Holes and bring the Plate down. I have plenty of Water Pressure but i did not want to Go more until i get a Enertia or Powertech... I hate doing things TWICE for no reason.

Keep You posted...If you have ideas.. All Ears.. I surely do not mind being the Guinea Pig..

Thank You Robert