MTF
FRF Addict
This is copy and paste from an TSB I found last year. I will try to find the link to this.
I know yours is not Supercharged but it's happened to NA 6.2L too.
Sure looks like it's worth a look, you never know.
Ford heater hose causing noise that sounds like a bad supercharger
Ford cars and trucks have a heater hose restrictor in the water feed line from the water pump to the heater core it’s held in place by a metal band around the hose.
The restrictor is used to protect the heater core from too much water pressure which could damage the core and cause water leaks.
On Whipple supercharged F150 5.4 3v trucks and 6.2 Raptor F150 and F250 trucks
Sometimes the restrictor inside the heater hose comes apart and gets pushed down the line or breaks apart, when this happens it will create a lot of noise inside the passenger compartment at high RPM’s and will sound like there is a problem with the supercharger compressor.
To check if the restrictor has been damaged,
find the heater hose from the water pump to the firewall and find the metal band clamp if the hose is soft inside where the clamp is then the restrictor is gone.
In some cases the restrictor will be caught at the end of the hose where it connect to the heater core
We don’t recommend that you remove if from the line and reinstall the hose as heater core damage could happen.
If you buy a OEM replacement heater hose it will come with the restrictor already in the line .
Ford also made a retro fit restrictor for the older cars and trucks and it could be adapted to the current ones to repair this problem
but it looks like it could cost as much as a new hose E7VY-18D358-A
Restrictor retrofit for 85-2002 Ford cars and trucks
This one requires you to cut the hose and clamp it in
Part number F1UZ-18D406-A
Excerpt from an old TSB for 1985-2002 Ford cars and trucks
Article No.: 01-15-6 Date: 08/06/01
add a restrictor (part F1UZ-18D406-A) on the inlet hose with the arrow facing
the direction of coolant flow (toward heater core). Cut the line and install with 2 hose clamps. It is important that
the restrictor be installed in the right direction of flow and as close to the engine block as possible
(not near the heater core itself).
The flow controller goes in between the intake manifold fitting and the heater core, as close as possible to the intake manifold. Here is the proper procedure:
1.Allow the engine to cool and follow all shop manual safety precautions and procedures regarding the engine cooling system.
2.Remove radiator cap and drain coolant from the system until the level is below the heater inlet hose fitting on the engine manifold.
3.Remove the heater inlet hose from the fitting on the intake manifold.
4.Cut the hose in two, approximately 2 inches from the end that attaches to the fitting on the intake manifold.
I know yours is not Supercharged but it's happened to NA 6.2L too.
Sure looks like it's worth a look, you never know.
Ford heater hose causing noise that sounds like a bad supercharger
Ford cars and trucks have a heater hose restrictor in the water feed line from the water pump to the heater core it’s held in place by a metal band around the hose.
The restrictor is used to protect the heater core from too much water pressure which could damage the core and cause water leaks.
On Whipple supercharged F150 5.4 3v trucks and 6.2 Raptor F150 and F250 trucks
Sometimes the restrictor inside the heater hose comes apart and gets pushed down the line or breaks apart, when this happens it will create a lot of noise inside the passenger compartment at high RPM’s and will sound like there is a problem with the supercharger compressor.
To check if the restrictor has been damaged,
find the heater hose from the water pump to the firewall and find the metal band clamp if the hose is soft inside where the clamp is then the restrictor is gone.
In some cases the restrictor will be caught at the end of the hose where it connect to the heater core
We don’t recommend that you remove if from the line and reinstall the hose as heater core damage could happen.
If you buy a OEM replacement heater hose it will come with the restrictor already in the line .
Ford also made a retro fit restrictor for the older cars and trucks and it could be adapted to the current ones to repair this problem
but it looks like it could cost as much as a new hose E7VY-18D358-A
Restrictor retrofit for 85-2002 Ford cars and trucks
This one requires you to cut the hose and clamp it in
Part number F1UZ-18D406-A
Excerpt from an old TSB for 1985-2002 Ford cars and trucks
Article No.: 01-15-6 Date: 08/06/01
add a restrictor (part F1UZ-18D406-A) on the inlet hose with the arrow facing
the direction of coolant flow (toward heater core). Cut the line and install with 2 hose clamps. It is important that
the restrictor be installed in the right direction of flow and as close to the engine block as possible
(not near the heater core itself).
The flow controller goes in between the intake manifold fitting and the heater core, as close as possible to the intake manifold. Here is the proper procedure:
1.Allow the engine to cool and follow all shop manual safety precautions and procedures regarding the engine cooling system.
2.Remove radiator cap and drain coolant from the system until the level is below the heater inlet hose fitting on the engine manifold.
3.Remove the heater inlet hose from the fitting on the intake manifold.
4.Cut the hose in two, approximately 2 inches from the end that attaches to the fitting on the intake manifold.
Last edited:
