Quincy 325 compressor

[Ironman]

No, this thread is not about a great yardsail deal. I wish it was.
Without air my shop is about as useful as an extra ball. Most tool just act dead.

I noted it took away to long and could not get up over 130 psi. So I pulled the dripstick and there was more blowby than normal...I think. So I figured lets pull some valves out and peek at the bores. They looked beautiful so no gouged cylinder wall. But I noted aluminum flakes and one piece of aluminum 1/2" long trapped in the HP exhaust valve. I dumped the oil, clean and clear and no flakes in the sump.
Con rod big ends are snug and have no play. So where is this aluminum coming from?
HP piston is cast iron. checked by a magnet.

What I don't know is what the LP piston is made of. I put a bore scope down and it looks great.
Does anyone on here know if it is cast or aluminum? I rebuilt this thing sometime around 2010, and I can't remember.

[milomilo]

Originally Posted by Ironman

No, this thread is not about a great yardsail deal. I wish it was.
Without air my shop is about as useful as an extra ball. Most tool just act dead.

I noted it took away to long and could not get up over 130 psi. So I pulled the dripstick and there was more blowby than normal...I think. So I figured lets pull some valves out and peek at the bores. They looked beautiful so no gouged cylinder wall. But I noted aluminum flakes and one piece of aluminum 1/2" long trapped in the HP exhaust valve. I dumped the oil, clean and clear and no flakes in the sump.
Con rod big ends are snug and have no play. So where is this aluminum coming from?
HP piston is cast iron. checked by a magnet.

What I don't know is what the LP piston is made of. I put a bore scope down and it looks great.
Does anyone on here know if it is cast or aluminum? I rebuilt this thing sometime around 2010, and I can't remember.

Maybe you can find something out here.

[Ironman]

I've been there and the only useful thing is their how to find a dealer and I already knew that. National Process in Edmonton is the Quincy supplier and parts people, and they are closed today.

The dash number is the Revision of Construction number. Mine is 325 -4 and currently they are up in the 130's. Natpro guys could not believe how old it was and still thumping along. I don't know if any other compressor sells undersize bearings and oversize rings and pistons but Quincy does plan for you to grind and bore their pump. Mine is still with standard crank journals.

I guess the head is going to have to come off.
If the piston is aluminum, that could mean there is a broken ring, or they have aluminum buttons on the end of the wrist pin so the pin can not go traveling and gouge the bore.

[Ironman]

Today I looked hard in the crankcase and could not see, feel, or hear any mechanical issues.
So I made sure all the valves in the head were clean and washed them, and started it up.
I immediately found that the tank check valve was not holding air in the tank, the last valve in line and one I didn't check. Here is what I found in the check valve.

So I finally got through to the NatPro guys and they were not a fountain of info. Told me it may have come from the aluminum gaskets that seal the valves in the head. Except my valves have brass gaskets.
After cleaning out the check valve I started it up again, and built 80lb and shut it off. The tank check is holding, but the cylinder head gasket on the low pressure cylinder side of the head was blowing air. So I have a blown head gasket. Tomorrow I will do some brain surgery on the head.

[Shade Tree Welder]

Just hire a democrat, they blow a lot of hot air, and are about as one way as you can get.

[Ironman]

Originally Posted by Shade Tree Welder

Just hire a democrat, they blow a lot of hot air, and are about as one way as you can get.

Unless they get a chunk of reality stuck in their teeth

[Ironman]

Today I was fired up to take the head off the compressor, and I pulled the head bolts and then realized I will have to move the whole machine away from the wall, remove the belt guard and flywheel, to be able to get the finned inter-stage cooler off the cylinder head as the Allen bolts are un-accessable otherwise. I found the thing too heavy to move and I'll have to get some young muscle before I proceed.

[midmosandblasting]

I thought you had a mini ex ?

[Ironman]

Originally Posted by midmosandblasting

I thought you had a mini ex ?

It can't reach in that far into the seacan where the compressor is. I've thought of it. I can move it, just have to rig things up for it, and time is short for me before winter. So I will take a few days to get there or I may be able to get the neighbors to help.

[Ironman]

I chained a post to the bucket to give me more reach, and was able to grab one end of the tank with a sling and swing it out from the wall. Then I removed the belt guard. More tomorrow.