Cat brakesaver help

Today I replaced the diaphragm. Has 65lb of air but still doesn't work? Help!

 

By spool, are you referring to the valve in the handle on the steering column? before I replace the diaphragm when I pull the handle all I could hear was are gurgling in the oil under the truck but since replacing it when I pull the air handle now I can now here the shaft engage under the truck that the diaphragm and springs are on.I know air is getting down there because when I unhook the airline and pull the handle there is air to it

 

I drove the truck around the block a few times and apply the brake saver multiple times and even drove with it on for a while and I thought I felt it just a little but I figured it would do more than what I was feeling I didn't know if there was a setting or adjustment on it somewhere. This truck came with it factory I'm assuming because it has all the gauges in the dash and everything the spool or shaft you're speaking of looked fine to me as far as no scoring. But this is a new beast to me. This truck we bought from out west and we never have seen a brakesaver here on the East coast. We just don't have much use for them out here I guess. we have the Appalachian mountains but they are nothing compared to the Rockies.

 

So would I be able to apply the brakes over while idling and see a reduction in RPM? I tried to look for a reduction in RPM several times while applying it but never could see one. However I pulled the handle and left it applied and drove it for about a half mile and when trying to shift gears I did notice that the RPM fell very fast between gears and made it difficult to shift but I honestly never felt like it was really doing what it probably should