Sears Two Stage Compressor Repair - Still No PSI

[sp73]

I picked up a golden oldie a month ago locally, and it has been great SO FAR.

It is an old sears two stage 30 gallon unit. Last week while it was running I noticed the rythmic "put put" sound of the compressor had more or less stopped. Pressure was at 150psi but after the tank went down I could no longer get the unit to produce any pressure whatsoever.
I removed the cylinder head and found two of the reed/flapper valves had broken from rust. I was able to source those and today I installed them along with a new gasket and belt for good measure. While I was waiting I rotated the compressor by hand and did not hear or see anything that was concerning. The unit sounds normal now but... no pressure whatsoever. Everything is tight, and I do not hear any leaking. The only thing I have noticed by chance is that air seems to be coming OUT of the cylinder head cover through the air filter instead of going IN. Duh. What could I have done wrong, or what should I be checking at this point? The flapper/reed valves look flush...

 

[The Cobbler]

you have a twin cylinder, not a 2 stage compressor.
did you replace 4 of the valves? did you clean the mating surfaces? did you put the valve plate back on the same way as it was?

 

[sk farmer]

first of all. that is not a 2 stage. twin cylinder yes (says so on the tag), 2 stage no.

a 2 stage pumps air with the primary or larger first stage piston into the secondary or 2nd stage smaller compressing it more than a single stage.

 

[The Cobbler]

not sure if it's just the picture, but the valves seem to be butchered where they are attached to the plate. are they sitting nice & flush to the valve plate?

 

[larry4406]

Looks like the gasket is wrong.

Original picture on the left shows that the reed valve section was gasketed off from the other ports. Repaired picture on the right shows ports encircled.

 

[seber]

In addition to the wrong gasket, did you check the intake valves to see if they are also broken?

 

[larry4406]

In addition to the wrong gasket, did you check the intake valves to see if they are also broken?

Intake valves?

He shows pictures of the broken reed valves and the replaced reed valves.

 

[Citation]

I'm not certain what we are looking at here (using Larry's post for the pictures). I see the manifold side of the valve plate. I see a left side picture with broken outlet valves and a right side picture with repaired outlet valves. I don't see an obvious issue with the gasket in the left picture. Within the head the two outlet valves dump into a common manifold so no reason why there needs to be gasket between the outlet valves. Without seeing the gaskets I can't be certain but the gasket in the right picture appears to be the one between the valve plate and cylinders.

Do we know if the inlet valves are good? Has the valve plate been pulled of the cylinder block?

 

[The Cobbler]

Looks like the gasket is wrong.

this one for the win? makes sense to me

 

[sp73]

Looks like the gasket is wrong.

Original picture on the left shows that the reed valve section was gasketed off from the other ports. Repaired picture on the right shows ports encircled.

It was this. I received the wrong gasket and clumsily installed it.

I picked up a FEL PRO gasket making kit this morning, traced what needed to be covered and cut my own gasket. I also cleaned up the valve plate more thoroughly.

The compressor is working normally now. I appreciate ALL replies - and my bad for calling this a two stage compressor!

 

[larry4406]

It was this. I received the wrong gasket and clumsily installed it.

I picked up a FEL PRO gasket making kit this morning, traced what needed to be covered and cut my own gasket. I also cleaned up the valve plate more thoroughly.

The compressor is working normally now. I appreciate ALL replies - and my bad for calling this a two stage compressor!

Excellent!

Welcome aboard by the way!

 

[Rinspeed]

Great to hear you got it working and welcome to GJ.