Fuel valve question
Thread Starter
|
Road Master
Joined: May 2007
Posts: 794
Likes: 3
From:
Fuel valve question
Any need to close the valve when parking a 96' 80 evo?
From what I've read, the valve needs engine vaccuum to open anyway's, so the chances of flooding the carb should be slim.
Thx... Ben.
From what I've read, the valve needs engine vaccuum to open anyway's, so the chances of flooding the carb should be slim.
Thx... Ben.
Road Warrior
Joined: Jan 2007
Posts: 1,276
Likes: 8
From: Minneapolis Area, MN
RE: Fuel valve question
I only closed mine in order to run the float bowl dry. Now I've got an aftermarket without the vac operation so whenever I remember I'll shut it off. The lack of the vac valve makes it easier to drain the tank for removal.
Intermediate
Joined: Jun 2007
Posts: 40
Likes: 0
From:
RE: Fuel valve question
Never had it happen, but remember rubber diaphrams in the valve get old. Should the valve stick open,it can overflow the carb,and fill the engine. Unlikely to happen,ussually when the valve goes bad,it won't open leaving you stranded. Remember what can go wrong will. HD insalled the valve for a reason,and good habit to get into. I went to a Pingel valve for a S&S carb,and now have to shutthe valve off .It doesn't take too long to re-train yourself.
Seasoned HDF Member
Joined: Dec 2004
Posts: 11,068
Likes: 1,473
From: Texas! Ya mean there's someplace else?
RE: Fuel valve question
Vacuum operated petcocks = stupid (EPA idiots). Sooner or later the valve will fail. It'll probably fail in the closed position and strand you somewhere far from home, though. 
If it fails open, or starts leaking by, the odds are your carb float valve will notice it, and decide, "Hey, this is a great time to stick open, too!" Since newer carbs don't have overflows (EPA idiots, again) the gas will then drain into your engine, wash all the oil of the cylinder walls, accumulate in the crank case, then be drawn into the oil tank and/or be puked out the breather. Oil dilution happens, and your cylinder walls are worn the next time you start up. If you're really unlucky, the gas builds in the combustion chamber and when you start the motor the pistons try to compress it. They can't compress a liquid so something breaks.
All this is somewhat tongue-in-cheek. But it has happened.Gas diluted oil is bad, and oil washed off the cylinder walls is worse.
Shutthe valve.
If it fails open, or starts leaking by, the odds are your carb float valve will notice it, and decide, "Hey, this is a great time to stick open, too!" Since newer carbs don't have overflows (EPA idiots, again) the gas will then drain into your engine, wash all the oil of the cylinder walls, accumulate in the crank case, then be drawn into the oil tank and/or be puked out the breather. Oil dilution happens, and your cylinder walls are worn the next time you start up. If you're really unlucky, the gas builds in the combustion chamber and when you start the motor the pistons try to compress it. They can't compress a liquid so something breaks.All this is somewhat tongue-in-cheek. But it has happened.Gas diluted oil is bad, and oil washed off the cylinder walls is worse.
Shutthe valve.
Thread
Thread Starter
Forum
Replies
Last Post
