Over the past few months, I have had a few oil free air compressors give myself and friends a little grief. Some of the original parts are of inferior quality so I thought I would share some of the fixes in case there are others with these quiet little buggers needing some repair.
The first was one was of the a dual compressor variety for an Udon Map poster. It must have fallen over while shipping as one intake filter was broken off in the head. It needed new air filters, new rubber anti-vibration mounts on one compressor and a cylinder head (due to the threads of the air filter being stuck past my easy out capabilities). He was in no hurry and I actually ended up buying from him after the repairs for my own home use as my home compressor was very loud and leaking more oil than Exxon Valdez.
Air Filters 32 baht each x 2 plus shipping
https://my.lazada.co.th/customer/order/ ... t_manage.1
Mounts 56 baht each x 4 plus shipping
https://my.lazada.co.th/customer/order/ ... t_manage.1
Cylinder Head 386 x 1 plus shipping
https://my.lazada.co.th/customer/order/ ... _manage.1#
The second oil free compressor was one that had been running pretty much 24/7 since late 2019. This 1500 watt Dental clinic version purchased on AliExpress and the vendor could never bring himself to reply with my request for a consumable spare part list. Since it was a continuous use application this bothered me a little. A couple months back, it was heard to be louder, less pressure and less volume at the air stones. There was also some metal powder landing around the motor. This was not a concern for the air being pumped as I have a series of filters on the pressure side but I do need this to run. Not bad really for over 3 years of continuous service.
I decided to replace this badged 1500 watt >200 cfm dental office compressor unit (no tank or pressure switch) temporarily with two off the shelf tanked oil free ones from Lazada and Thai Watsadu set to run alternating an hour on, hour off as these are not designed for continuous use. I rigged up a couple of fans to blow on them while running for good measure as I needed them in place for about a week.
I brought the alleged 1500w dental one to my Udon home workshop and pulled the heads off. The sleeves were obviously scored and leather rings were worn. After some futzing around, I ordered replacement parts based on the badged 1500 watt model as these seem fairly generic along with some rods, piston tops and a seal kit. Well, the parts came after several days but didn’t fit. I found another Lazada site quoting exact dimensions of the parts so ordered another set from them. These parts were for a 1100 watt compressor so I guess mine must have been mislabeled. Parts came in a few days so I replaced the two sleeves and two leather piston rings. After some light wire brush cleaning and torquing the Allen bolt head screws down in a cross pattern, I gave it a whirl. To my surprise it was back to its silent self so back into service it went with a new junction box and hour meter this time adding quick connections for easy service replacement in future.
Sleeve and ring 205 baht each plus shipping:
https://www.lazada.co.th/products/i4267 ... em_title.1
I ordered another set for the next preventative maintenance in say two years time.
The third oil free air compressor is a cute little guy great for home use of tyre inflation, air blast cleaning and light duty nail gun use. I don’t think it is anywhere big enough for mechanics air tools but most homeowners don’t have those anyway. This one suffered from a fitting or hose leak after only a small amount of use. I began taking it apart with the appropriate spanner and boom the pipe thread sheared on the tank, same happened to the fitting on the head as well as the fitting into the solenoid valve. The fittings seemed to be made out of some really cheap compressed aluminium dust or something then glued into the pipe thread with some type of epoxy. Certainly not brass.
I spent some time shopping at the usual haunts and found a hose and check valve three-way fitting at ToolPro but not the 90 deg fitting for the head not the solenoid valve body. I did purchase an assortment of easy outs but these things were not budging, I tell you. I set the thing aside as I didn’t have an immediate need to repair it at that time.
Last Saturday a friend came ‘round with his air compressor (identical to my little one, we'll call this number four). We fixed the intake mud wasp plugging with the appropriate drill but it was observed to have a slight leak at the check valve fitting. I should have known better but just touching the fitting with a spanner resulted in another dissolved fitting and a non-functional compressor. I loaned him one of my spares for the time being.
Now I’m looking online in earnest and found all the spares we both need so I order them and some extras for the other two dual pump compressors I have in standby service which will undoubtedly need the same parts sooner or later. I then purchased the appropriate drill bits for ¼” NPT and 3/8” NPT as well as pipe thread taps at ToolPro. These were 27/64” and 7/16” for ¼” NPT but 3/8” required 9/16” and 37/64” so I had to settle for 14.5mm and a taper drill to bevel the starting area a bit. All in the drill bits and taps were 1686 baht.
90 deg 1/4" NPT fitting 89 baht, 40 cm hose 169 baht, 3/8" NPT three connection check valve 119 baht plus shipping for all:
https://www.lazada.co.th/products/winne ... 7764.html?
IP65 solenoid valve and body assy 250 baht plus shipping (only used the pressure body):
https://www.lazada.co.th/products/i3092 ... em_title.1
EDIT: This link was incorrect in the original post.
Spare parts came yesterday, I drilled, tapped (using my 1/2" chuck impact drill), vacuumed it and changed two check valves, two solenoid bodies, two 90 deg fittings in the heads with Teflon tape on the NPT threads (no epoxy) and two 40cm hoses on two Polo compressors. Both fixed and working without leaks with real brass fittings in about an hour. Very satisfying repairs.
Lazada links and pics above in case any of you UM posters have a similar product.
Air Compressors
- Potamoi
- udonmap.com
- Posts: 554
- Joined: April 11, 2022, 11:53 am
- Location: Halfway between Llanfairpwllgwyngyllgogerychwyrndrobwllllantysiliogogogoch and Ona-i-Lau
Air Compressors
Last edited by Potamoi on July 14, 2023, 3:48 am, edited 1 time in total.
I fear the man who drinks water and so remembers this morning what the rest of us said last night
Benjamin Franklin
It is better to remain silent and be thought a fool than to talk and remove all doubt
Maurice Switzer *(assumed)
Benjamin Franklin
It is better to remain silent and be thought a fool than to talk and remove all doubt
Maurice Switzer *(assumed)
Re: Air Compressors
My first compressor was a single piston type. It ran without any problems for several years. The problem was that it just didn't put out enough volume. I sold it to a friend and as far as I know, it still works. I then bought a rotary one HP unit. It worked fine for a year or so then would run but didn't produce any air. I shot some WD40 into the air intake and it started working again. The valve is a reed type and after the WD40 quit working, I took off the head and the reed check valve was greasy and sticky. I cleaned everything up and it is still working. Eventually the motor quit running. I decided it was worth buying a new motor. It is still working. If you just need to pump up a tire once in a while, a piston type is the most dependable. If you need more volume, then a rotary is the answer.
Re: Air Compressors
Good work from @Potamoi. With the outlay on tools, maybe start up a casual compressor maintenance business with the UM membership? Charge say 500 baht + parts (and BYOB)?
BTW, the unrepaired Exxon Valdez I acquired at "takeaway prices" is still leaking. It's buried under other stuff in the open shed but I see the seepage every few days when it dries out after the rain so it's still on the to-do list. Maybe I should bring it over some day?
BTW, the unrepaired Exxon Valdez I acquired at "takeaway prices" is still leaking. It's buried under other stuff in the open shed but I see the seepage every few days when it dries out after the rain so it's still on the to-do list. Maybe I should bring it over some day?
'Don't waste your words on people who deserve your silence'
~Reinhold Messner~
'You don't have to be afraid of everything you don't understand'
~Louise Perica~
"Never put off until tomorrow, what you can put off until next week."
~Ian Vincent~
~Reinhold Messner~
'You don't have to be afraid of everything you don't understand'
~Louise Perica~
"Never put off until tomorrow, what you can put off until next week."
~Ian Vincent~
- Potamoi
- udonmap.com
- Posts: 554
- Joined: April 11, 2022, 11:53 am
- Location: Halfway between Llanfairpwllgwyngyllgogerychwyrndrobwllllantysiliogogogoch and Ona-i-Lau
Re: Air Compressors
Noooooooooo... that's why it was free! Your scrap man can have it, please.
I fear the man who drinks water and so remembers this morning what the rest of us said last night
Benjamin Franklin
It is better to remain silent and be thought a fool than to talk and remove all doubt
Maurice Switzer *(assumed)
Benjamin Franklin
It is better to remain silent and be thought a fool than to talk and remove all doubt
Maurice Switzer *(assumed)
Re: Air Compressors
I'll rename it USS Arizona then.
'Don't waste your words on people who deserve your silence'
~Reinhold Messner~
'You don't have to be afraid of everything you don't understand'
~Louise Perica~
"Never put off until tomorrow, what you can put off until next week."
~Ian Vincent~
~Reinhold Messner~
'You don't have to be afraid of everything you don't understand'
~Louise Perica~
"Never put off until tomorrow, what you can put off until next week."
~Ian Vincent~