Dual Piston Compressor Head Problems

[Chris518]

My compressor was not working when I bought my deuce. I bought a gasket kit in preparation of tearing it down. I hit my first roadblock when taking the compressor 'block' off the base. How in the world do you get to the back inside nut?? I had the cooling hose (to the oil cooler) removed but there is no way to get a wrench or socket on it. I would love to get it off to clean off the mass amount of RTV on it now but maybe i dont need to. I got the head off and the cylinder walls looked really good and they were moving up and down with zero resistance. So I am thinking the issue is in the head. I removed the intake valves and they are in good condition. They seem to be closing as they should. When trying to remove the exhaust valves, I cannot get the nut (?) off to get into the valves and springs. I didnt have an allen that big so I made one from a hex head bolt. I have soaked it good in PB Blaster but it wont budge. Is this a nut? Compression fit?
I am not sure if it is even worth it because when i press on the valves they seem to spring just fine. I would not think that the exhaust valves would prevent pressure from building but I would feel better to just put my eyes on all parts. This is also the first time I have broken a compressor like this down so I dont have much reference. But I guess thats why you guys are here!

Lots of questions above so in summary...
How do I get the back inside nut off the compressor block?
How do I remove the exhaust valve collett (or should even bother)?
Any other suggestions what I should investigate?

 

[cattlerepairman]

This post has some pics of a twin piston Midland taken apart : https://www.steelsoldiers.com/threads/air-pump-rebuild-questions.68764/page-2

 

[Chris518]

This post has some pics of a twin piston Midland taken apart : https://www.steelsoldiers.com/threads/air-pump-rebuild-questions.68764/page-2

Great pics! Thanks for sending. Doesn't look like they had disassembled much in the head itself (but every other piece is broken down) so now I am thinking these must be pressed in, not screwed it.

Anybody have any tricks to see if the seats on the exhaust valves are good? Should they hold fluid if I pour a little in? I guess same question applies to the intake valves (reeds).