Coolant Flow Restrictors for Heater Core

Discussion in 'Fox 5.0 Mustang Tech' started by savegoodautonfg, Jul 22, 2006.

  1. i was reading about heater core replacements and i found on a few websites about people using coolant flow restrictors and i'm not sure where they exactly go and if you need 1 or 2 and/or where to buy them? anyone help please?

    Also does ford sell the replacement heater core hoses?
  2. It should come with the restrictor already in the hose when you buy a new inlet hose.(the larger of the two hoses).

    Mine did.Bought it from Ford.
  3. Hopefully this will answer some of your questions.

    Yes, you can still get the heater core restrictor from Ford
    Part # E7VY-18D358-A, but it’s around $16, or you could use a 13 MM socket to do the same thing from everything I’ve read.

    Yes you can still get the heater core and hoses from Ford, which personally I think is your best bet.

    You’ll only need 1 restrictor, it will go in the inlet hose which is the larger hose, or uppermost of the two hoses that plumb the tubing outlets at the rear of the engine to the heater core connections at the firewall.
    The restrictor is designed to reduce the pressure of the coolant particularly during hard acceleration and deceleration, so it’s only function is to protect a fragile heater core design and nothing more.

    What the Restrictor looks like
    View attachment 453765

    Stock Location
    View attachment 453767

    If you've had a "gurgle, squeal, and/or moaning" noises created (in the 2000-4000 rpm range) in some 5-liter cars (most of which were built prior to 5/3/93). The condition is caused when a restrictor valve moves out of its proper position. The fix involves positioning the restrictor in the engine end of the hose and securing it with a clamp."

    This is how you need to locate the restrictor.
    View attachment 453769
    View attachment 453771
  4. Almost Stock,

    thanks for the reply man great info,

    the restrictor won't move at all though?

    so pretty much take the inlet hose and where the hose curves, put the restrictor before that or what? the pictures show them in different spots?
  5. Go by the first diagram.

    Remove the inlet hose from the heater core and slide the restrictor in that end, tapered end in first.
    The restrictor won't move around any (or mine hasn't for 17yrs:D ) because it's pinned next to the end of the heater core, and is a tight fit in the hose.

    The second diagram is a so-called fix for the gurgle sound that some say they had is the only reason I posted that diagram.