VP SX speedometer issue (going backwards at speed)?

zagger

Petty Officer 2nd Class
Joined
Sep 8, 2010
Messages
191
had a strange thing happen the other day when doing some sea trials with my new Regal bow rider. The speedometer started going backyards way below 0. At first I thought the tube separated from the drive and was dragging creating vacuum at speed. Once home I checked all fittings and all was OK. I blew little air into the pick up hole and little water came out, no other obstructions or chunks of seaweed. Did that three times till no more water came out and the spedo started to work again. My question is if I have a hole in the line and it fills up with water I would think the gage would simply stop working, what would make it go backward?
 

Don S

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62,321
Re: VP SX speedometer issue (going backwards at speed)?

How new is your Regal? The SX drive doesn't have a speedometer pickup in it?
 

zagger

Petty Officer 2nd Class
Joined
Sep 8, 2010
Messages
191
Re: VP SX speedometer issue (going backwards at speed)?

Got the boat 10 months ago but it is an 08 model. Left over boat locked in bankruptcy court when dealer folded and recently released. It is a 5.0 GXi (270HP) SX 1:6 drive. I have been working a lot and so far only managed 8.4 hours on the motor. It does have a pick up on the drive. I'm just puzzled how the speedo would turn backward unless there was vacuum generated in the line?
 

Don S

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Re: VP SX speedometer issue (going backwards at speed)?

5.0GXi what. There is a letter or two after the GXi, that is what explains things. 5.0GXi could be a 94 model with TBI.
As far as the speedometer goes, I have no idea. As far as I know, there is no connection to the drive. Is your speedometer electronic? Does it have a separate transducer or pickup tube on the transom?
 

zagger

Petty Officer 2nd Class
Joined
Sep 8, 2010
Messages
191
Re: VP SX speedometer issue (going backwards at speed)?

It is an MPI.
For use with 2007-2011 applications, this new generation Volvo Penta SX single prop outdrive is the best single propeller alternative on the market. The wide rudder area gives precise handling - especially important for close quarters maneuvering. Top speed is maximised by the hydrodynamically designed lower housing which also host technically advanced transmission features. SX is a solid base for true boating fun!

The SX single propeller drive is of the most modern design, featuring exhaust through the propeller hub, for quiet and efficient operation, a cone clutch for easy and smooth shifting, pattern-matched spiral bevel gears for optimum strength and minimum gear whine, and a break-away shaft coupling to prevent costly drive train repairs.

The hydrodynamic design of the lower drive housing ensures excellent course stability both at high speed and when maneuvering at low speeds and in reverse.

The drive is equipped with easily maneuvered hydraulic power trim for obtaining the best running position at different sea and load conditions.

For maximum corrosion protection the drive has gone through a 23-step paint process and comes equipped with sacrificial anodes both on the drive and transom shield. Either right- (standard) or left-handed propellers can be used. A choice of stainless steel and aluminum propellers are available for different applications.

Features:


?Single propeller drive which can be run with both right- and left-hand propellers
?Cone clutch
?Coolant water intake for the engine located at the lower part of the drive
?Pattern-matched spiral bevel gears
?Through-hub exhaust
?Overload protection sleeve (break-away coupling)
?The drive can be tilted 55?
?The drive can be turned 28? in each direction
?Built-in kick-up function to reduce possible damage, in the event the drive strikes an underwater object
?Belt-driven power steering pump (option)
?Active corrosion protection as accessory

Other Features Include:

?Hydro-dynamically improved design giving better speed and performance.
?Even more durable internal drive train for longer service life.
?Lower weight for better performance.
?Reduced maintenance need (e.g. only 2 anodes and maintenance-free gimbal ring).
?Higher capacity through-the-drive exhausts for greatly reduced sound and smell.
?Integrated speedometer pick up.
 

zagger

Petty Officer 2nd Class
Joined
Sep 8, 2010
Messages
191
Re: VP SX speedometer issue (going backwards at speed)?

Bump.
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: VP SX speedometer issue (going backwards at speed)?

I have no clue.
 

zagger

Petty Officer 2nd Class
Joined
Sep 8, 2010
Messages
191
Re: VP SX speedometer issue (going backwards at speed)?

LoL, honest answer. I have no clue either, thanks for a reply. Later Zig.
 
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