I have a Magnum 42 pro that has been sitting for quite awhile. It turns over with lots of compression. It will start if I put fuel in the carb. It runs that out then quits. I have change fuel tanks, took the carb off and does not seem to be plugged any place. I can see the fuel going up to the carb when it starts but that is it. What are some other things I should look for.

There's probably something plugged up inside of the high speed needle. Pull it out and check to see if something is clogging it up.

Ken

Remove the needle valve and then with fuel in the tank, gently blow into the vent line. You should see a stream of fuel come out the needle valve hole with a very slight blow. If it takes any presure, pull the tank and check for a clogged clunk, and for cracked or bad lines. If that seems OK, screw in the needle valve just enough to get a seal with the O ring and again blow into the vent line. You should see fuel exiting the spray bar. Repeat with the idle jet needle. Put the needles back to factory start settings and see if you can get it running then.

If the engine has been setting for a while, it may be a good idea to take the carb off and put it in a small jar of fuel overnight to desolve any varnish built up. I would pull the tank and replace all fuel lines also just as a mater of preventive maintenance.

The fact that it will start and run out the fuel you put in the carb throat indicates a fuel supply problem. It's somewhere between the clunk and the spray bar.

What happens if you hold your finger over the muffler exit and hand crank. Does it draw OK?

Don

I put a new tank on it. I will try blowing with the needle valve out and see what happens.

Remove the NV entirely, and you may see a ring of goop around it near the tip. Wipe it clean.

Then plug the fuel inlet on the carb, and use a syringe to blow some fuel thru the NV's hole to blow out the inner passages. Then repeat with the fuel inlet open, to blow that out. Betcha it runs after that!

J

Ok when I take the needle valve out and blow through the vent line, lots of fuel. When I put the needle valve in just so it seats it takes a lot of pressure to get it in the carb. So how do I clean it.

By taking it out an blowing through it you probably dislodged anything that may have been in there. Put the needle valve back in and see if it will run now.

Ken

Hey Jburry
I bet you are right. It is now running. Thanks

My pleasure!

J