egr check valve

[Troy]

I've been detecting a bit of exhaust gas inside the cab and after a wee bit of investigation, I noticed the check valve has fallen off the tube that siphons the exhaust up to the space between the engine and firewall.

I was just barely able to get it back on but it is still billowing out exhaust as I could not tighten the u-bolt but only was able to hay-wire it to stay on. I suspect either the egr solenoid is not activating or the check valve is not opening but due to the poor location I find it virtually unserviceable, looking for best options

[Gary Lewis]

Since you have EFI I think you have to ensure the system works properly or the computer will get its knickers in a twist.  And, since I am not familiar/au fait with that system, I can't comment further.  But, if it will help, here's an illustration thereof:

[85lebaront2]

I believe the piece you are talking about is the Thermactor pipe that delivers air to the cylinder head ports. It is clamped to the back of each head and has a check valve where the air from the Thermactor pump is delivered. They are very prone to rusting out and leaking exhaust gas underhood.

[Troy]

That is a great name for it, what isn't great is access. From what I was able to see with my ageing eyes was that everything was intact (components displayed no structural integrity issues) except for the likely corrosion that allowed the intended compression from the u-bolt to actually loosen it off rather than seize it on. This is not to imply that the part is functional. Even to haywire it on, I had to resort to using two 2ft pry bars as you cannot actually put your hands on it or reach it. It's an unfortunate engineering choice, it appears service requires pulling the engine. Much sadness.

[Gary Lewis]

So sorry!  At least you know what it is, although that is small compensation.  

[85lebaront2]

It is possible on a 302 to get it off without pulling the engine, upper part of the intake has to come off if it is the one on the back of the engine. If it is the one going down to the catalytic converter an exhaust shop can probably fix it.

[Troy]

Probably doable if you were to pull the head(s). It certainly becomes a value consideration at that point

[Rembrant]

85lebaront2 wrote

It is clamped to the back of each head and has a check valve where the air from the Thermactor pump is delivered.

Here is a picture that shows where it attaches if anybody cares. The bolts are only very short, and mine popped right out without issue. This is on my '84 of course...not sure how different it is on an EFI 302.