TOPIC: Tach problem and oil gauge leak. Need help

Last season, my tach worked on and off, however, it hasn't this season. When I turn the ignition on, the needle jumps to the highest rpm and pegs itself. It just stays there when I start the engine. Last year, it would do this and then right itself within a few minutes. At lower rpms, it would be kind of bouncy, but once I hit 2-3000 RPms, it would be pretty steady. I removed the 3 connecting wires in the back of the unit and cleaned them good, but It didn't help anything. (There is no sending unit with this model. it is all in one: unit has 3 terminals on the back. The drawing shows the optional sending unit that would come with the next years model). However, the wires at the start button are very rusty. Anyone have suggestions or ideas?
Also, the oil gauge is leaking at the connection in the back. I believe this gauge is not electrical, but pressure controlled. So, would it be ok to put some pipe thread tape on it, or should I cut the copper tubing and re-flare it (assuming it is flared)?

Anyone have ideas? i'm going on vacation and will hopefully end up at the Buffalo Antique and Classic Boat Show. Would really like to have it working by then:)

Only help I could offer is to make sure all wire connections are clean on both ends, if any wires are showing signs of corrosion or rust they probably need replaced? It really sounds like the tachometer might be going bad, but I'd check the above mentioned first.

The oil line coming into the back of the gauge is copper tubing? Most I'm familiar with used a compression fitting, which sometimes needed to be replaced due to over-tightening. If it is a flare, you can check to see if it's sealing against the gauge by the shiny ring where it should be seating against the gauge. Sealing the threads may not do any good, but it couldn't hurt to try the teflon tape. (just use it sparingly, and wrap in the direction of the threads so you won't back it out when tighening the nut).

HTH

It sounds like your tach is bad or a wire maybe corroded through inside the insulation.

The gauge end of your oil line might be flared or have a ferrule type compression fitting on the line. You could try to tighten the fitting. Best would be to re-flare or replace the ferrule. Teflon tape on the threads will not help.

If the tach is bad, can it be fixed? Should I open it up myself or send it somewhere, or should I look for an NOS?

Got it working! Tons of corrosion on the terminals and wires under the dash. Cleaned it all off and the tach stays very accurate! I took the copper tubing off the oil gauge. It is flared. Since I don't have access to a flare kit, I just cleaned the flared surface of the gauge and the tubing. Put some liquid thread sealer on the fitting and put it back together. Seems as though it greatly reduced the leaking even at high RPms. I will fix it right come fall. Thanks catfink for your help.