the air compressor is on a 1941 aec matador for the air breaks after having problems with our air compressor (because the screw in the valve had worked lose and shattered the top of the piston to bits) we replaced it with a second hand one that we was lucky to find it seams to be working ok but the air pressure will not go up any more than 40 psi/lbs, the gauge pressure should rise until the governor "cuts out" at 90 lb. per sq. in. does anyone please have any knowledge about this kind of stuff? if so we would be very grateful thanks
would it be possible to make 1 good compresser out of the 2 ? and do you think this could help?

we have a 1941 aec matador and are having problems with the air line/breaks what happened was coming home from a rally not far from home we went over a speed hump and something started clanging, we stopped and the noise went away, but then we noticed that the air pressure was not going up, the tank helled what air it had but would not fill, well we finally found it out to be one of the piston’s in the air compressor, we tracked a second hand air compressor down in barnsly, we put that on and the air pressure started to register but the most pressure we have got is 40 LBs despite giving the valves in the compressor cylinder head and the valves and stuff at the front of the air tank a thorough cleaning, does anyone have any suggestions of what it could be or what to try next please {s.o.s}
thanks for the reply D our old compresser was working fine before the piston went would it be best to make one good one out of the two (ie take the piston out of the new one and put it in our old one
thanks for the reply we are new to doing things on the computer so hope we are doing it right. I dont think that there is more air than we think in the tank, going of the way the breaks are oporaiting, the breaks are working but with not much pressire and the air is used very quickly, there is a buzzer on the truck to let you know that the air is low and that stops buzzing at about 80 and we are only getting 40
what do you mean about the blow of valves, do you mean the valves in the compresser? and if so how can you tell that thay are not working right?