Tahoe Q7I SSI Advice

Status
Not open for further replies.

jonjon74

Cadet
Joined
Dec 14, 2015
Messages
27
Hey guys,

I brought a used 2010 Tahoe Q7I SSI with a Mercruiser 5.0L MPI (260HP) Alpha One, Drive Gear 1:47 that was neglected. I had it serviced at an authorized Tahoe dealer, I had them do a full service (impellor, oil change, spark plugs, computer, etc) including compression check. Everything checked out 100% they even said the computer reported only 24hours of use.
Before service and since service it getting low RPM and low Speed. The factory prop is a Mercury (Diameter 14 - 1/4", Pitch 21 3 Blade (Model832832A45 21P) ? Aluminum) and only getting 3900RPM and 41MPH on GPS. I posted in the Mercruiser and Prop forums and getting mixed results, some say engine and some say prop. Since them I also tested 3 other props see below for results.
I wanted to reach out to other Tahoe owners and get their personal experience. Any input would be helpful as I am at a loss on which direction to turn.

Thanks in advance.



Prop 1 (Original prop) Diameter 14 - 1/4", Pitch 21 3 Blade (Model832832A45 21P) - Aluminum
41 MPH (GPS) at WOT with 3900 RPM


Prop 2 (Test prop) Diameter 14 - 3/4", Pitch 18 3 Blade -SS
47 MPH (GPS) at WOT with 4500 RPM
- Better Hole Shot


Prop 3 (Test prop) Diameter 14 - 1/4", Pitch 16 4 Blade -SS
46 MPH (GPS) at WOT with 4600 RPM
- Great Hole Shot

Prop 4 (Test Prop) Diameter 14 - 1/4", Pitch 15 4 Blade -SS
44 MPH (GPS) at WOT with 4900 RPM
- Best Hole Shot yet. Really jumps out of the water.

Q7I SSI Specs
2010 Q7I SSI, Length 20'6" Beam 96" 45Gal Fuel Tank, Dry Weight 3031 lbs.
 

KD4UPL

Senior Chief Petty Officer
Joined
Feb 13, 2010
Messages
653
You're engine WOT speed needs to be whatever that engine is listed for. I don't have the data in front of me but your manual should have it. I suspect prop #3 is the one you want.
 

jbcurt00

Moderator
Staff member
Joined
Oct 25, 2011
Messages
24,829
Jonjon, please dont start multiple topics in multiple forums about the same problem

IMO, this is not a problem related to your boat being a Tahoe.

The Mercruiser forum or prop forum topics you've started have gotten several replies, most from the same handful of members.

This topic is closed

Jonjons Mercruiser topic
http://forums.iboats.com/forum/engin...ed-and-low-rpm
 
Last edited:
Status
Not open for further replies.
Top