wonky tach - removing sport dashboard?

I have the same problem that developed this fall. I was just too busy to chase it down,it will be interesting to me anyway on how you fix it. I do know that you unloosen the 4 thumb screws and lift up the dash to get underneath it. The wire harness is long enough to lift it up.

Update:

With help from my wife (just holding things in various positions while I worked), this wasn't too hard to do. 4 thumb screws (whew, those mounting points on the dash pad look rough!), one more screw on the far left side of the dashboard, tilt the wheel down, and the dashboard was loose.

Once the dash is loose, there is some "give" in the wiring harnesses to move it a few inches in whatever direction. As mentioned earlier in the thread, the best working position was rotating the whole dashboard upward, giving you access to the back of the gauges if you stand at the helm.

The tach has the typical potentiometer that allows settings for 4, 6, 8 cylinder engines. It can be adjusted with a flathead screwdriver. I "exercised" that a few times between the various settings, then re-centered the adjustment at the 8 cylinder setting. Unfortunately, the boat is winterized, so I didn't have the chance to see if that fixed the wandering tachometer issue. I'm pretty confident it will - at least this has worked on other boats in my past.

While I had access to the back of the dash, I unhooked the speedo tubes and blew air through them, to clear 'em out for winter. One tube had a little water, while the other was clear. A 3/8" wrench takes the nut off the back of the speedo, allowing you to remove the pitot tubing from the hose barb.

During reassembly, I noticed a slightly loose RCA cable on the stereo and the electric hookup for the depth finder had come undone. My wife was able to reattach them as I slowly moved the dash panel back into place.

Thanks again for your advice, and I hope my explanation will prove useful to someone else searching in the future.

8122pbrainard,

That's a good idea - I have a bunch of little things on the "punch list" to keep me occupied in May, when I pull it back out from the storage barn across town. That should be one of them.