High Atlitude Blues

Dheimbuch

Cadet
Joined
Jul 19, 2006
Messages
10
Okay, 20+ years of boating, I finally made it to a high alt. Lake (Approx 6000 ft). I put on a good power prop, but never touched the Carbuation! The boat is a Sanger with about 260 hp and is normal ran at lakes between 800 to 1500ft elevation! IT WAS A DOG! Took forever to plane without a skier, and would not plane with a single skier(200lb). What do I need to do if I decide to go back up to a high alt. Lake?
Is a Carb adjustment all she needs, Is there a rule of thumb to get it close?
 

Dheimbuch

Cadet
Joined
Jul 19, 2006
Messages
10
Re: High Atlitude Blues

Oh yeah, One more question, what elevation do carburated boats start experience significant power losss? If it is set up to run 800 to 1500 ft, will the power loss be noticable at 3000ft? 4000ft?
 

bruceb58

Supreme Mariner
Joined
Mar 5, 2006
Messages
30,587
Re: High Atlitude Blues

What pitch prop do you use at 800 ft and what did you end up getting fro 6000ft?

I have a house at Lake Tahoe and I am able to use my sea level prop but I am a little underpropped at sea level.

I believe the rule of thumb is 5% power reduction for every 1000ft of elevation gain due to less oxygen.
 

Dheimbuch

Cadet
Joined
Jul 19, 2006
Messages
10
Re: High Atlitude Blues

bruceb58 said:
What pitch prop do you use at 800 ft and what did you end up getting fro 6000ft?

I have a house at Lake Tahoe and I am able to use my sea level prop but I am a little underpropped at sea level.

I believe the rule of thumb is 5% power reduction for every 1000ft of elevation gain due to less oxygen.
Yeah, I went for a 19 pitch to a 17 pitch (Only because I had it as a abackup). You don not have to adjust the Carb for the thinner air?
 

PuddleJumper

Petty Officer 1st Class
Joined
Jun 6, 2005
Messages
314
Re: High Atlitude Blues

If you are only occasionally going to high alt water I would suggest lower pitch yet on the prop. If frequent high alt then you could consider re-jetting carb
 
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