Shut off valve
Pro
Joined: Sep 2002
Posts: 620
Likes: 2
From: San Antonio TX
Unless you already have a leak in the core, it's very advisable to circulate coolant through the core every once in a while to keep it fresh. In other words, you need to open the valve and drive around every once in a while.
Melting Slicks
Joined: Jan 2006
Posts: 3,028
Likes: 2
From: North NJ
Originally Posted by lucky76
I don't know why some people try to reinvent the wheel. They sale these cutoffs at most auto supply stores, no reason to go to Home Depot and buy valves and fittings. Go to and autosupply store and say "I need a 5/8 inch and a 3/4 inch heater hose cutoff valve."
.....would you beleive that I don't have an autoparts store within 50 minutes of me?! home depot is 11 minutes away.A NAPA would make a fortune near me catering to all the ricers.
Advanced
Joined: Feb 2007
Posts: 57
Likes: 0
From: Apex NC
Not sure if my cutoff valve is original equipment, but it seems to have a small vaccum hose to it? Would that mean that it is actuated by the vaccum? I need to replace it as it look very bad. Not sure if it is even working? On the bright side at least now I am replacing things for looks and not to get the car running....
Drifting
Joined: Jan 2001
Posts: 1,841
Likes: 3
From: Halifax, NS, Canada
Not sure if my cutoff valve is original equipment, but it seems to have a small vaccum hose to it? Would that mean that it is actuated by the vaccum? I need to replace it as it look very bad. Not sure if it is even working? On the bright side at least now I am replacing things for looks and not to get the car running....
Safety Car
Joined: Oct 2004
Posts: 3,725
Likes: 5
From: Minnesota
I already have a shutoff with an elbow on my manifold which works great but the idea of putting another one just before the water pump may not be a bad idea. That way if your heater core or a heater hose lets loose at an inopportune time all you'd have to do is shut off the second valve and no more leak.
You have to be prepared for anything when driving these relics.
You have to be prepared for anything when driving these relics.
Le Mans Master
Joined: Jan 2007
Posts: 8,000
Likes: 3,339
From: Omaha NE
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Not sure if my cutoff valve is original equipment, but it seems to have a small vaccum hose to it? Would that mean that it is actuated by the vaccum? I need to replace it as it look very bad. Not sure if it is even working? On the bright side at least now I am replacing things for looks and not to get the car running....
Instructor
Joined: Jul 2006
Posts: 237
Likes: 0
From: walker louisiana
i have one like bobs77vette....it works fine but its ugly....no off. like i said i have the same setup....iv been looking for something else that looks like it didnt come from home dep./lowes/hardware for my home hot water heater ...something alittle tricker looking....
...something alittle tricker looking....
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Instructor
Joined: May 2003
Posts: 220
Likes: 0
From: Hilton Va
I think you should put a cut off on both hoses. One puts a lot of constant pressure on the heater core. The reason I say this, is I put a heater core in an S10 and not long after I put a cut off on one of the hoses and within a year it started to leak just a little. May just be a one of those things but it got me to thinking.
Instructor
Joined: May 2003
Posts: 220
Likes: 0
From: Hilton Va
I think you should put a cut off on both hoses. One puts a lot of constant pressure on the heater core. The reason I say this, is I put a heater core in an S10 and not long after I put a cut off on one of the hoses and within a year it started to leak just a little. May just be a one of those things but it got me to thinking.