What's in a speedo housing?

[John Hart]

Last summer, I ran my Seacoaster for the first time... The speedometer did not register anything... Previously, I had blown air through the gray tube from the transom, and that was clear. Also, I made sure the hole in the plastic unit mounted to the transom was open as well..

Before I begin dismantaling the dash assembly, I thought I would ask if there are common things to go wrong on these....? My appears to be original... Airguide I think (It's in storage now)

Anybody have any comments on the items to check first.... anything to lube, or free up... is there a lot to the gauge or not much?

Thanks in advance.

[Phill Blank]

The speedo is very simple inside. Basiclly you have a bent tube attahed to a rack and pinion. The opinion is attached to the needle shaft. When air pressure fills the tube it tries to streighten out and in doing so it pulls on the rack which in turn turns the needle of the gauge. It is identical to a pressure gauge on an air compressor only it work on less pressure. You possibly have a leak in the tube in the gauge or the tubing from the peto tube at the transom, or the inlet to the guage is plugged with debris or corrosion. If you do take the gauge apart be very carefull as they are delicate. You may want to try to find a replacement speedo that works and replace the one you have rather then try to fix that one.

Good Luck!

Phill