Tach and Speedo Problem
 

I have a 2002 Mariah Shabah 202 and can't get the tach or speedo to register anything. I found originally that the pickup line for the speedo was disconnected. I reattached it and still nothing. I detached it and also from the back of the speedo, blew air through the line, reattached both ends, and still nothing. I checked all the fuses in the fuse block near the gauges, replaced one blown (not certain what it went to though), still nothing. I also checked the small orfice above the nose cone with a small drill bit and didn't see anything in there. Any other suggestions? I've focused all my efforts on the speedo, but the tach is inoperable also. What am I missing?

Re: Tach and Speedo Problem
 

Did they both stop working at the same time? If so, I would check power & ground to the gauges.

Re: Tach and Speedo Problem
 

I dont think there is anything electrical (other than the light) with the speedo. It simply runs off pressure from the tube. I would disconnect the tube from the back of the speedo then use a compressor & blow air backwards thru the line to see if it comes out the small hole at the front of the outdrive. It really does sound like there is a leak or a blockage somewhere along the line.

As for the tach, i agree with DCB. The 'likely' cause is a bad ground/connection somewhere.

Re: Tach and Speedo Problem
 

Thanks. I'll try air again with disconnecting the pickup line. I'll see if I can trace the power lines to the tach. Do you have a wiring diagram or other manuals for this model?

Re: Tach and Speedo Problem
 

There are benefits to becoming a Contributing Member to the MOC and this is one of them.

Re: Tach and Speedo Problem
 

Make sure you dont blow compressed air into the speedo or you will have to replace it..... :(

Re: Tach and Speedo Problem
 

Ok, so I blew the line out again from the back of the speedo to the outdrive...not sure if anything came out of it, but there was significant water in the driveway under the foot, so I'm assuming I cleared the line. Now, when I took the line off the back of the speedo, it was secured with a cable tie...I broke that one removing it and used a new one when I put it back on and got it as tight as possible with pliers. Took the boat out today, and...nothing...also, now it leaks from the back of the speedo when in drive, so obviously water is getting from the outdrive to the speedo. Should the line to the speedo have been installed with a better clamp instead of a cable tie? Any inclination as to what's happening here?

Also, I haven't worked on the tach yet, but I'll become a contributing member so I can track down some wiring diagrams.... Thanks for the help!

Brandon

Re: Tach and Speedo Problem
 

Yeah, i would like to hear about possible causes also. My speedo is working but the tach is not.

Re: Tach and Speedo Problem
 

I have the same problem. No tach. Doesnt move from 1000 RPM when key is turned on or turned off.