Speedos don't work

[hanski]

I puchased a 98 Legacy and have tried sinking in the speedos with a GPS several times. I have disassembleled them at the rear of the boat.... make sure air passes through. I can't get them equal or sometimes even to work...any advice would be great.

Sometimes they can be 20mph apart.... I know they are not acurrate

[DKJBama92Mariah]

I'm not sure if the air pressure (pitot) type speedos are adjustable. If they are, there would be some kind of knob on the back of the speedometer itself. Otherwise, check the hose for its entire length for any kinks. Also, you can use a straightened paperclip to make sure that the hole in the pitot tube on the back of the boat isnt clogged with anything.

Cheers,
DKJ

[selle92]

are the fins straight?

I have a new replacement on one side and the other is original and slightly curved or bent. I get about 2-5 mph play between the two.

I split the difference and chalk it up to owning an older boat.

Might be the case, but do check for air line flow, and possible corrosion at the end as well.

[dndsam]

Do the rest of the guages work? I had to replace an ECM on my 99 because the entire dash went dead. If you are looking to replace the pickups, the Airguides are hard to find since they are no longer produced. Disconnect the hose at the pitot and blow back against the pick up. Becareful not to break the tip of the pitot since the threaded piece is plastic. I have had wood chunks lodged in mine. Causes a few inaccurate readings.

Most of the suction gauges adjust by an adjustment screw on the front of the face. On my saltare there is a little alan-headed bolt that will adjust the calibration. I just dial it in with my gps and it works alright.

[Ed Obermeier]

If the other guages aren't working or are acting odd, it's definitely the ECM. I've replaced TWO of them in my 2000 Legacy. The problem turned out to be the o-rings failing where the tubes from the pickups attach to the ECM module, allowing water into the ECM. The 2nd time I replaced it I plugged both lines with golf tees, left them unattached, and I just run speed off the PerfectPass. I'd rather be without the one speedo (I can get the speed from the PP) than without all of the gauges for a third time.

[Ed Obermeier]

If the other guages aren't working or are acting odd, it's definitely the ECM. I've replaced TWO of them in my 2000 Legacy. The problem turned out to be the o-rings failing where the tubes from the pickups attach to the ECM module, allowing water into the ECM. The 2nd time I replaced it I plugged both lines with golf tees, left them unattached, and I just run speed off the PerfectPass. I'd rather be without the one speedo (I can get the speed from the PP) than without all of the gauges for a third time.

[KenG]

A 1998 uses a conventional gauge package, nothing computer controlled.

The speedometers are the standard Airguide setup. There is an adjustment knob on the front of each speedometer for making minor adjustments.

The most common problem is a blockage in the pitot tubes. I use a small drill in a pin-vise to clean mine.

You could trace the hoses from the pitot tubes to the speedometers to ensure no kinks or breaks. This is a chore since these hoses connect to a small chamber located beside the fuel tank under the fuel fill. You need to move the fuel tank to access this area. A sign of a damaged hose is water leaking somewhere where you normally would not expect to see water.

Perhaps the mechanisms inside one of the speedometers is damaged. You could try switching the hoses at the back of the speedometers to see if the problems remains with a specific speedometer.

Good luck...\

--KG--