Air compressor volume problem

Hi men, fng here. Need advice.
I recently bought a 2005 379 pete with cat power. My problem is this truck is very very sloooow to build air. I thought compressor, changed it this morning. Nope, 400 bucks thrown away. So I thought spin on filter at air dryer. Nope. Did the soap suds test at the exhaust vent at the bottom of air dryer, no bubbles. Checked the intake for obstructions, nothing.

Whats next to check or replace?

 

Not yet. I’ve seen fuel lines do that very thing. Will check that first tomorrow. I did crank it with filter off and volume supplied there is very low.

 

The lines to the air dryer have a good flow. The port coming out is way less but its not leaking out of the exhaust port. Seems like the dryer is bad but i cant understand why the relief valve at compressor isnt popping off if there is an obstruction. I sprayed down the entire dryer with a soap solution. No bubbles.

I should mention too that once the air pressure is built up, the truck will hold pressure overnight.

 

Checked that too. Thanks tho because I am open to any suggestions. I have seemingly checked everything but the right thing......

 

Thanks. Didn’t have the right fittings today. This one has one big flare fitting inlet and two half inch tubing outlets.

My 98 pete had a dryer that you could just pull the in and out lines and thread them directly together.