Air system problem

I just checked my air sys. from 60 lbs to 90 lbs in 60 seconds. is this o.k. I had new compressor put on, just cause the ole one, original one was slow to build air. the rebuilt one did not build any faster than ole one. fixed a lot of leaks, like the one at the unloader on top of compressor. it would only leak if the engine was running. plus fan clutch. anyway, this comp, was put on 3 years ago, when I first got truck 11 years ago with 400,000 miles on it, it would fly right up to 120 from 40-50. I still don't like how long it takes now, but as long as it within specs, I'll keep it like it is.

 

If you are getting 60 to 90 in 60 seconds that is good now you have to hook it up to shop air and with a bottle of soapy water find and fix all the leaks.
Test the maxi-pots for leaking back into the exhaust valve of the brake relay. If there is air coming out of the exhaust port you remove the hose to the brake pot port to isolate which one it is.
If you trade it in with problems they will reduce the trade in value, when the used truck inspection is done.

 

That will only test the trailer system.

Put a stick on the brake pedal to hold it down and then do a walk around, this will apply air to the entire brake system.

Actually the DMV air test will show a leak. Build pressure, shut motor off, block wheels, release brakes, check pressure loss (less than 3psi in one minute) then apply brakes fully and hold, supply guage must not drop more than 4 psi (after the initial application drop) in one minute. (these numbers are for combo's, single units are 1 psi less)

Sounds to me like a weak compressor. Is there a spec for max time it should take to build air? [digging out the book]

Book says the compressor should build from 85psi to 100psi at operating rpm (1500) within 45 seconds.