I recently ordered a Rolair JC10 from Sean at the Tool Nut See More Here and I'm currently very happy with it's performance.
I had my Thomas T-635HT for 2-3 years and the noise level always bothered me and the output did somewhat but more and more recently it had become frustrating. So since I had a replacement unit I decided to take the little Thomas apart to see what made it tick, or not. The Thomas is a lubeless design and uses a couple of reed valves (flappers), a wobble single piece piston/Connecting Rod, Coated Cylinder, and what appears to be a graphite coated piston ring seal. So in opening it up I was pretty shocked to see the damage the cylinder has suffered over time.
Valve Plate
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Pictures of Old Cylinder
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Piston and Ring Seal with head and cylinder removed
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Rebuild kit that came in the mail last night. I bought two rebuild kits at Grainger and they were an unbelievable $15 each! They are now showing discontinued on their website Grainger Link Most of the kits were closer to $150 so I'm not sure how I lucked out on this.
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Contents and Instructions
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After removing the fan cover and fan, you need to loosen the screw holding the rod to the bearing and the screw holding the crankshaft/flywheel to the motor shaft.
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Here's the crankshaft / bearing
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Once removed it's just a matter of twisting and lifting the piston and rod from the assembly.
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Here's what a new piston looks like and with the unit almost fully assembled.
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Ok the rest is just changing out the reed valves that are held on with a single screw each and putting the valve block and head back on. This complete rebuild took me about 30 minutes to complete. I made a video of the unit pumping up from empty to shut off prior to dis-assembly and it took about 1 min. 30 sec., after the rebuild the first start up without allowing for break in was just about 1 min. A huge difference for sure and it was also quieter when running. Still too loud for my taste but better none the less. I didn't do a cycle test before dis-assembly but it's now less than 14 seconds from the time it kicks on to pump up and shut off. Sorry I didn't really gather much more data that that but if you have a similar unit with moderate to heavy use you may want to check it out. Since they used o rings for sealing, taking the head off for inspection doesn't cause any parts damage that would then need to be replaced. Let me know if you have any questions.
Chris...
I had my Thomas T-635HT for 2-3 years and the noise level always bothered me and the output did somewhat but more and more recently it had become frustrating. So since I had a replacement unit I decided to take the little Thomas apart to see what made it tick, or not. The Thomas is a lubeless design and uses a couple of reed valves (flappers), a wobble single piece piston/Connecting Rod, Coated Cylinder, and what appears to be a graphite coated piston ring seal. So in opening it up I was pretty shocked to see the damage the cylinder has suffered over time.
Valve Plate
[attachimg=#]
Pictures of Old Cylinder
[attachimg=#]
[attachimg=#]
[attachimg=#]
Piston and Ring Seal with head and cylinder removed
[attachimg=#]
Rebuild kit that came in the mail last night. I bought two rebuild kits at Grainger and they were an unbelievable $15 each! They are now showing discontinued on their website Grainger Link Most of the kits were closer to $150 so I'm not sure how I lucked out on this.
[attachimg=#]
Contents and Instructions
[attachimg=#]
After removing the fan cover and fan, you need to loosen the screw holding the rod to the bearing and the screw holding the crankshaft/flywheel to the motor shaft.
[attachimg=#]
Here's the crankshaft / bearing
[attachimg=#]
Once removed it's just a matter of twisting and lifting the piston and rod from the assembly.
[attachimg=#]
Here's what a new piston looks like and with the unit almost fully assembled.
[attachimg=#]
[attachimg=#]
Ok the rest is just changing out the reed valves that are held on with a single screw each and putting the valve block and head back on. This complete rebuild took me about 30 minutes to complete. I made a video of the unit pumping up from empty to shut off prior to dis-assembly and it took about 1 min. 30 sec., after the rebuild the first start up without allowing for break in was just about 1 min. A huge difference for sure and it was also quieter when running. Still too loud for my taste but better none the less. I didn't do a cycle test before dis-assembly but it's now less than 14 seconds from the time it kicks on to pump up and shut off. Sorry I didn't really gather much more data that that but if you have a similar unit with moderate to heavy use you may want to check it out. Since they used o rings for sealing, taking the head off for inspection doesn't cause any parts damage that would then need to be replaced. Let me know if you have any questions.
Chris...
