Coyote Air Intake Bleed Cap

[JeffP]

Went out for a nice drive today only to have my coolant let loose all over the highway, managed to limp it back home so at least avoided the tow of shame.

Can any one recommend a quality part for this crap $.05 cap that decided to let go?

https://thefactoryfiveforum.com/attachment.php?attachmentid=203459&d=1725141251

If you've got a Coyote, might want to check yours.

[JeffP]

Ordered one of these: https://a.co/d/h5SoeHK

A little disappointed FFR includes a 3/8 Vacuum Cap in the Coyote Fitment pack for this. Obviously a vacuum cap isn't going to withhold the pressure, temps, and chemicals that a coolant circuit requires.

[michael everson]

I drill and tap the hole for the temp sensor. Its 1/16 NPT I believe
Mike

[Nigel Allen]

I would argue for that vent to be used for its intended purpose. Better to be safe than risk cooking a cylinder head.

[JeffP]

I would argue for that vent to be used for its intended purpose. Better to be safe than risk cooking a cylinder head.

I don't believe its intended purpose translates to crate use, maybe for a stock mustang. I followed the instructions and used the provided part. Off-season project may be to tap it and put a proper bleeder valve in it. I already have the temp sensor mounted elsewhere.

I also learned the ECU will go into limp mode when it reaches a high temp.

[Nigel Allen]

A builder down here capped his Coyote bleed off and heater ports per FFR instruction. It resulted in a cooked left hand bank due to air pocket. Wouldn't like that to happen to anyone else.

Cheers,

Nige

[edwardb]

I would argue for that vent to be used for its intended purpose. Better to be safe than risk cooking a cylinder head.


I don't believe its intended purpose translates to crate use, maybe for a stock mustang. I followed the instructions and used the provided part. Off-season project may be to tap it and put a proper bleeder valve in it. I already have the temp sensor mounted elsewhere. I also learned the ECU will go into limp mode when it reaches a high temp.


A builder down here capped his Coyote bleed off and heater ports per FFR instruction. It resulted in a cooked left hand bank due to air pocket. Wouldn't like that to happen to anyone else.

Cheers,

Nige

The Factory Five Coyote installation instructions cap off several Coyote cooling ports, including this one, and show installing a relatively basic and simple coolant overflow tank. The stock system used in Mustangs is admittedly more complex. But how Ford designed it and has several advantages including being self-burping. Not to mention whatever consequences may occur if the caps fail. Many of us choose to install with that setup. I've documented it in both of my Coyote builds. In that case, the connection in question is routed to the expansion tank.

[JeffP]

The Factory Five Coyote installation instructions cap off several Coyote cooling ports, including this one, and show installing a relatively basic and simple coolant overflow tank. The stock system used in Mustangs is admittedly more complex. But how Ford designed it and has several advantages including being self-burping. Not to mention whatever consequences may occur if the caps fail. Many of us choose to install with that setup. I've documented it in both of my Coyote builds. In that case, the connection in question is routed to the expansion tank.

I already have the hose running from under the radiator cap to an expansion tank - would I run this one to another port on that same tank?

[edwardb]

I already have the hose running from under the radiator cap to an expansion tank - would I run this one to another port on that same tank?

I don't know. If guessing, I'd say I doubt it. You're using the setup from the Factory Five instructions. Others have done it and it works. Capping that outlet is part of the scheme. Assuming you stay with it, I'd recommend something more robust like described in previous posts. I was describing how the Mustang setup is plumbed, which many have used and IMO is a better setup, and where that connection goes in that case. The OE setup doesn't use a T-filler or traditional radiator cap. The cap on the expansion tank is used for filling and checking the level.

[Nigel Allen]

I don't know. If guessing, I'd say I doubt it. You're using the setup from the Factory Five instructions. Others have done it and it works. Capping that outlet is part of the scheme. Assuming you stay with it, I'd recommend something more robust like described in previous posts. I was describing how the Mustang setup is plumbed, which many have used and IMO is a better setup, and where that connection goes in that case. The OE setup doesn't use a T-filler or traditional radiator cap. The cap on the expansion tank is used for filling and checking the level.

No, you cant run the hose to your overflow tank. With the engine running, there is a continuous flow of coolant out of bleed point, back to a header tank, which then 'drains' back into the Coyote. I have the Ford plumbing diagram for the Coyote, on my work computer, it's very helpful. Will forward it to you when I get in tomorrow. I feel it is best to trust the OEM when in doubt.

[JeffP]

Thanks everyone for the guidance as always. I'm going to replumb it following these guys thread: https://thefactoryfiveforum.com/showthread.php?46857-Gen-3-Coyote-Coolant-Hose-Upgrade-Parts (Thanks a ton for putting all the part numbers!!)

[Nigel Allen]

G'day JeffP,

This is the Coyote plumbing drawing taken from Gen1 install manual:

203562

Also stipulates:
If a heater circuit is not used then the heater supply must be connected to the heater return to allow air to
be purged from the right hand cylinder head and provide sufficient coolant flow through the right hand
cylinder head. Install a 5/16" (0.3125) diameter restrictor in this hose.

Hope this helps.