Motor Performance and fish finder?'s

[Bigbass91]

I ran my motor today(60hp Merc.) it started on the first turn idled great ranout good but when I really tacked it up it had a slight miss at times. The fuel tank was really low did not know if that would have something to do with it but just wondering what the miss is. I also got may fish finder set up and was just wondering if you can test them without being in the water? It was picking up a reading from the ground.

[bentpole]

Glad you got to run your motor,(hope it was in the lake:D )& not on them hose pipe connectors.The high speed miss could be in the Carb-If the boat has been setting up any lenth of time.The Jets in the carb- are small & it don't take much to plug them up,ol'gas & oil mix will tarnish.
As far as the depth finder,No there is not much you can do out of the water.

[Barnacle Bill]

Your depth finder may or may not get a reading out of the water but it won't accurate. It won't hurt it. As for the miss, you may have been getting a little air in your lines from the fuel sloshing around from being so low. I change the plugs in mine once a year wether they need it or not.

[papasage]

some depth finders will go into a simulater mode if the on button is held down for a short time .
as far as the motor it could be low on fuel my evinrude wll act up especialey on take off . if it still does it when full check this site out . T M D is a merc teck and knowes about other brands or some one on the site does .
http://www.themarinedoctor.com/cgi-bin/YaBB.pl

[zappaf19]

When the fuel gets low it is easy to pick up a small piece of dirt. Or when you take off the gas has moved back and the engine is sucking a little air.
Bill

[crappie joe]

I have a 40hp force mercury ,do have to tear down the carb to clean the jets?
Can you spraycarb cleaner in there to clean them up?

[papasage]

you might put carb and injector cleanner in the gass and run it and that might help . spraying int carb doesent git to high speed jets . jusr streight into tyhe crankcase and that depleats the oil gas ratio.

[Moose1am]

You may have some foreign matter in the bottom of the gas tank that got sucked up into the gas line. Or it could be any number of other problems. Take it too the mechanic and have it looked at.


As far as the depth sounder, yes you can get a reading from it without water. But the range is very limited. I can test my depth finder by placing a solid object under it and within a foot or two. I then get a reading but it's shows as 4 times less than it would in water.

Depth sounders use sound waves to measure distance. Sound travels four times faster in water than in air. So there is 4 times the difference in the depth readings in air. And the sound will not travel very far though air like it does in water.

So if you are 1 ft above the concrete driveway the depth will show up as 4 ft deep. You may get a second echo at 8 ft if the signal is strong.

I ran my motor today(60hp Merc.) it started on the first turn idled great ranout good but when I really tacked it up it had a slight miss at times. The fuel tank was really low did not know if that would have something to do with it but just wondering what the miss is. I also got may fish finder set up and was just wondering if you can test them without being in the water? It was picking up a reading from the ground.

[Barnacle Bill]

I have a 40hp force mercury ,do have to tear down the carb to clean the jets?
Can you spraycarb cleaner in there to clean them up?

Spray cleaner will no nothing but clean the throats. Try running a can of Sea Foam (Napa or Autozone) through it. That is some fantastic stuff.

[FisherMike]

If the motor is running rough at high speed and there is a fuel obstruction. That will cause a lean fuel mixture and if not corrected will do motor damage!!!
Make sure you have all fuel line and carburetor connections tight and there are no air leaks.
With out knowing how long the motor has been setting or how it ran the last time out, it's difficult to trouble shoot.
I agree with the consensus to clean the carbs although I would do the obvious things first.