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my m37 has the fueltank vent line taken off and plugged with a cap,if I replace the lines do I need the vent line , I know its for fordging and I think it is supposed to go to the air cleaner ,I wont be doing any fordging .does it need a vent line .

macibell111 wrote:does it need a vent line .

only if your gas cap seals

Hi macibell,

Yes, you need a vent for the tank. It can either be via a hard line, like you're talking about, or with a vented fuel cap. Or both. But the tank needs to be vented.

regards,
bob

thanks for the info ,I will put in a vent line

Don't our gas caps vent until you put them in the fully closed fording position?

They do if you have one of those gas caps with the selectable vent.....for those of us without them.....no. The cap on my AF truck is original and doesn't have that feature. And none of the manuals I have talk about closing the fuel cap vent for fording operations. So either the cap you are referring to was introduced later, or is not the original cap for an M37. Not trying to stir up an argument or anything close......I've picked up a few of those gas caps at meets.........I've just never seen any M37 manual describe them.

Anybody know what the deal is with the gas caps with the selectable vent feature?

regards,
bob

I see my cap has a small hole drilled in the center of it so I guess it would be consider it vented??

There should also be a similar hole on the underside of the cap as well. Some people modify their caps to be vented by drilling these holes. Blow thru the hole on the inside and verify it comes out the other side. If so....you're vented!

regards,
bob