How about a model number? You seem to be saying that instead of the vent hose releasing vapors- it is pressurizing the tank and pushing it through the cap? If you were to remove the vent hose from the tank side and run it- what happens?

I have the same problem with toro model 20370 gas cap leaks no matter what I do to secure it

I have the same problem with my Toro 20370. Gas leaking from the cap.I made a gasket for it....no more leak

The gas tank opening in out of round (oval shape). Check it.

always_breeze is absolutely correct. filler neck not oval by measurement (~1/2inch difference east-west vs north-south!), and mating surface of filler neck is no longer flat - the cap's o-ring not mating at north-south surfaces.

The oval-ness is caused by the 2 tabs on the cap - they squeeze on the east-west sides of filler neck when cap in place, AND THE TANK's SOFT BLACK PLASTIC 'COLD FLOWS' OVER TIME with the uneven pressure, ending up oval and out of flat.

This is a disgustingly poor design, AND TORO SHOULD BE PROVIDING FREE TANK+CAP REPLACEMENTS for at least the safety hazard reason, if not for the defective design.

I considered shaving the top mating surface of filler neck so the cap's o-ring can seal against it, but WHY SHOULD I? IT's DEFECTIVE!

we all complained to TORO, by letter, stating these facts, I feel we might shame them into action, unless someone knows of TORO already having offered a recall on this dangerous design. Just a matter of time before the pooling gas on the mower deck and resulting vapor reaches flash point when it comes in contact with hot muffler!

I agree the filler spout area should have been reinforced with metal or additional plastic collar inserted , additional gasket will solve this leakage . My friends has the same issue after two yrs and mine after 6 does not ...yet ! He stores his frequently within direct sun light , were as I always store mine indoors , any effect or coincidence ?

thanks for the posts folks...after first attempting to replace the gas cap (craftsman, AWD push mower) with another new OEM cap, and realizing it wasn't the cap per se but a design flaw as you and others elsewhere have enlightened me to, I decided to take the rubber gasket off the new cap and put it on top of the existing gasket (of my original cap) and that solved my problem (for now?). After an hour of testing my modified cap, i virtually went from drip-drip earlier today to not a single speck of gas any where's near the cap and nozzle (with 3/4 tank). Note, the gasket I added sits closer to the top of the cap and thereby creating a tiered affect of the two gaskets.

Alrighty Then !

Has anyone got anywhere with an easy fix for the gas cap leakages ? Does anyone know if there was a recall ?

I loose half my gas thru the cap everytime I mow!

Just do what had been mentioned within previous comments !

Okay - let's try repeating this from yesterday: I, too, experienced the gas leak at the cap problem on a Toro TimeSaver w/Briggs Stratton engine. My fix was a simple hose clamp (see photos, below), which changed the oval to a round gas filler opening. Voila! Now, the cap is tight and leak-proof. No more nuisance and possibly dangerous gas leaks.

Why the change to the over engineered (and has to be more expensive to mfg.) O-ring design in the 1st place. I never had any leak problems with the old gasket type cap unless the gasket wore out. Change should be to better something & not just for the sake of change. Going to try the hose clamp option 1st. THX for info.

For what it's worth, I had the same issue this week, after 7 trouble free years with this mower. My hose clamp was a bit too wide(high) to allow the cap to properly close, and I was too lazy to go out and find a lower profile hose clamp. I simply removed the o-ring, cut a strip of electrical tape 3/16" x8", and wrapped it around the cap body, in the groove that holds the 0-ring, so that the tape overlaps itself. Then replace the o-ring over the tape. It now fits just snug enough, with no leak.

Over time this injected molded plastic tank filler become distorted from uv exposure . Any of the listed resolutions effectively prevents future leakage !

Craftsman mower with Briggs & Stratton engine, leaked from day-1. slightly larger O-ring material diameter fixed problem but must be made of the Teflon material, Buna-n rubber material sticks & makes cap extremely hard to take off, gasoline is not a good lubricant.