Weird bottom machine problem.

Hit-n-Miss · Post by **Hit-n-Miss** » May 3rd, 2006, 8:06 am

A friend of mine has a Lorance LCX-18c and when the boat is running or underway the screen is scrambled but as soon as you shut off the moter it clears up. Any ideas?????

The boat has a 302 inboard.

Post by **tin can** » May 3rd, 2006, 8:09 am

Define scrambled.
Does it do this with the motor idleing, or just when the boat is moving?

Hit-n-Miss · Post by **Hit-n-Miss** » May 3rd, 2006, 8:21 am

The overlay depth stays correct but the depth on the screen may go to 2000' and you can't see enough detail to make out the bottom contour or fish echoes. Makeing it impossible to pinpoint the structure you want to anchor on.

Heck you couldn't even see the yamaha when we ran over it. Maybe a filter or something might help? Oh' and yes it does it while just idleing.

Post by **tin can** » May 3rd, 2006, 8:31 am

I gather from your reply, this occurs at idle speeds. If that's the case, I would look at the routing of the transducer cable. If the cable is close to the ignition system on the motor, you'll get interfereance. If moving the cable doesn't solve the problem, look into installing a noise suppression condencer on the engine.

Post by **Dubble Trubble** » May 3rd, 2006, 9:25 am

I would also look to be sure the spark plugs are the resistor type, and the wires are in good shape. Also, check all ground cables to be sure they are good and solidly connected.

Hooked

chugbug · Post by **chugbug** » May 3rd, 2006, 1:30 pm

Sounds like a bad ground to me too.

Hit-n-Miss · Post by **Hit-n-Miss** » May 3rd, 2006, 2:05 pm

Installed an inline filter and one of those magnet chokes like on computer cables. Ran it in the yard before and after big difference in the clutter on the screen.

We will put in new resistor plugs before a water test, but I think its taken care of.

Thanks