What's the best way to avoid getting air in the system ?

 

Pre fill the filters with fuel before installing them and the pump the primer pump until resistance is felt, then pump it a few more times.

Then start the engine.

That's how I do it and the engines never miss a beat when started.

 

This engine doesn't have a hand priming pump.
So we just fill the filters.
After the last filter change it tried to fire after the service...but didn't catch, then it was hard to start.
This might have been my fault for not giving it any throttle when it tried to start ?

 

I've never seen a C15 without a hand pump, I would put the filters on dry, use the primer pump, no problem...

You don't have to touch the throtle pedal.

 

I still don't understand the paranoia around here about pre filling filters, but in any case, I agree that the C15's I've seen all have primer pumps.

However, in the absence of a primer pump you could use LOW PRESSURE compressed air to force fuel thru the system.

Diconnect the return line from the tank. Cap the return fitting on the TANK. Leave the fitting on the end of the return line OPEN.

Connect a blow gun to an air hose. Stick the blow gun in the tank filler opening with rags stuffed around it.

Pressurize the tank GENTLY until fuel runs out of the disconnected end of the return line. At this point, you know that fuel has been forced thru the low pressure side of the entire system.

Note: If you do not remove the return line from the tank and cap the fitting on the tank, you are just neutralizing your efforts, because you're sending the same PSI air pressure back thru the return line as you are sending thru the suction line, and therefore nothing will happen.

 

I have always filled the filters, with no problem. As long as the fuel you put in is from a clean source it will be fine. If you are that worried about it, put a plastic plug in the center hole and slowly fill the outer holes.

As far as no primer pump on a C15, go buy one and put it on in place of the cover plate where it should be.

 

That's just what I'll do.

click for pic.....

[/img]http://farm2.static.flickr.com/1416/...5a944ecb7c.jpg

 

Another thing you can do is fill the fuel filters with injector cleaner then dump the remainder in your tanks. I always carry a few gallons of injector cleaner with me. This isn't a trick, it's listed in the directions on the cleaner container.

 

One more thing to do is to continue to pump the primer as the engine is turning over. This usually takes two people one to turn the key and one to pump.
Full filters and priming during cranking is the fastest way to crank them.

Mad Fatboy