Lawn Mower Trouble

Xaviar

Okay. So new roommate went to mow the lawn a while ago. Miraculously lost the gas cap. Wonderful. I order a new one. Meantime, everyone tells roommate "Just go ahead and tape some saran-wrap over the gas tank and poke a few holes in it. It'll be fiiiine.." I am against this, but am super busy at work, so mostly just say "Whatever, just get it done." Works for a little while, but then dies and refuses to start.

New gas-cap in. Won't start. Neighbor suggests spark plug. New spark plug. Starts, runs for a few minutes, dies. Won't start. Wait a couple minutes, starts, runs for a shorter period of time, dies.

Google suggests a few things, so I check the oil, it's good. Clean the air filter. No change.

Pull the whole thing apart and clean everything I can find. (May have missed cleaning something, I don't really know small engines, though I am capable of taking things apart and putting them back the way they were.)

While doing this, I notice there is a bunch of sediment in the gas tank. I assume this is the real problem. Empty the gas tank trying to take most of the sediment with it, but there is still some in there.

Starts, runs great for about 5-10 minutes, then the same problem.

I assume it's the dirt in the tank that is the problem, but I'm scared to rinse it out, and I don't know any other way to get it out of there.
Help?
Or possibly I missed some other cause?

spool32

Remove the fuel line, rinse out the can, dry it thoroughly. Clean the fuel filter and hoses, and dry them thoroughly. Tell your roommate he's a silly goose. Saran wrap changes shape with heat, and your gas cap doesn't have any holes in it.

Ruckus

spool32 wrote:

Remove the fuel line, rinse out the can, dry it thoroughly. Clean the fuel filter and hoses, and dry them thoroughly. Tell your roommate he's a silly goose. Saran wrap changes shape with heat, and your gas cap doesn't have any holes in it.

Gas caps do typically have very small vent holes to prevent the gas tank from building vacuum.