mcdtommy23
Well-known member
O.k. this is the 4th time i've tried to post.
I have a 4 yr olf Harbor Freight 21 gal compressor. It was loud, would never go above like 85 psi, and seemed to take a long time to recover.
Step one was to rubber mount the compressor and motor;
step two was to remove the stock useless air filter;
When trying to mount the new air filter/silencer, I realized that the head used a whoo-flung-poo-semi-metirc-hybrid-china-thread. So I had to pull the head and re-thread to 1/2" NPT. While the head was off I figured it needed some milling, on the belt sander it went, then to the glass and sandpaper. The ports were about 3/4 of the way obstructed with casting flash and poor design so out came the Dremel and it got a port job. (total time about 4 beers).
Head re-installed with new silencer, and fresh speedaire syenthetic oil;
Next step was to adjust the pressure switch. I tried prying on the red on-off switch thinking that it needed to come off but it stays with the cover, just 1 phillips screw. There's about a 10mm bolt inside that I gradually began adjusting (clockwise) until I got the compressor to build to about 125psi just to the point where the pop-off on the tank was starting to leak a bit.
While putting the compressor back in it's spot I realized I needed some better wheels. Went over to the "just in case" shelf and got the $3.99 I'll use them some day Harbor Freight wheels. Mounted them and installed a new rubber tipped leg in the front;
Recovery time has decreased from 5 min 25 sec. to 3 min 15 sec. and that's at a higher psi, with less than 1/2 the noise. My t.v. is now louder than my compressor! Hope this can help someone with their compressor as well. --Tom--
I have a 4 yr olf Harbor Freight 21 gal compressor. It was loud, would never go above like 85 psi, and seemed to take a long time to recover.
Step one was to rubber mount the compressor and motor;
step two was to remove the stock useless air filter;
When trying to mount the new air filter/silencer, I realized that the head used a whoo-flung-poo-semi-metirc-hybrid-china-thread. So I had to pull the head and re-thread to 1/2" NPT. While the head was off I figured it needed some milling, on the belt sander it went, then to the glass and sandpaper. The ports were about 3/4 of the way obstructed with casting flash and poor design so out came the Dremel and it got a port job. (total time about 4 beers).
Head re-installed with new silencer, and fresh speedaire syenthetic oil;
Next step was to adjust the pressure switch. I tried prying on the red on-off switch thinking that it needed to come off but it stays with the cover, just 1 phillips screw. There's about a 10mm bolt inside that I gradually began adjusting (clockwise) until I got the compressor to build to about 125psi just to the point where the pop-off on the tank was starting to leak a bit.
While putting the compressor back in it's spot I realized I needed some better wheels. Went over to the "just in case" shelf and got the $3.99 I'll use them some day Harbor Freight wheels. Mounted them and installed a new rubber tipped leg in the front;
Recovery time has decreased from 5 min 25 sec. to 3 min 15 sec. and that's at a higher psi, with less than 1/2 the noise. My t.v. is now louder than my compressor! Hope this can help someone with their compressor as well. --Tom--
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