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Topic: aux air compressor comparison (Read 587 times) previous topic - next topic

aux air compressor comparison

Bought a Viair 450 c to plumb into my wet tank so I can bring air tanks up to 125 psi to air up tires. I have a Thomas 4104 for my air leveling and air seals and swapped it out with the Viair for a comparison test.
Tested 40 psi [cut in] to 80 psi [cut out], on both compressors. Found the Thomas took 100 seconds, and the Viair about 125 seconds.  The Viair does go to 150 psi though, good for bringing big air tanks up.
I guess moral of story is, if you can rebuilt the Thomas for less that $200, [price of Viair] it is probably worth doing.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: aux air compressor comparison

Reply #1
You can not rebuild for under $200.. I bought the viair also and like it . Little more noise but pretty close. Mine has 2 pumps and a tank and it's super fast..

Re: aux air compressor comparison

Reply #2
You can not rebuild for under $200.. I bought the viair also and like it . Little more noise but pretty close. Mine has 2 pumps and a tank and it's super fast..
Did you run separate relay for second  compressor, or bigger  relay, or use only existing relay for both?
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.


Re: aux air compressor comparison

Reply #4
I stand corrected... if you are going to tear it apart I would say do it right and get the major kit just in case. Might not need all the parts but just in case I would order the major kit. Might as well do it right if you are going to do it.

If I remember correctly one of the forum members ordered the major kit and had to use some of his old parts to make the rebuild work as the rod was different? But again to me if you want to take it apart I say do it right

Re: aux air compressor comparison

Reply #5
I got the major rebuild kit;  Value Brand Major Service Kit .630 C87866-P | Zoro.com

When I took the compressor apart I found that it didn't need the piston, rings, rod or bearings replaced, but I installed the new ones anyway.  I also checked the brushes and they were like new!

I was looking for minimum down-time, but in hindsight I should've checked things out and realized that the compressor didn't need a rebuild after 14 years.

Also, the Value-Brand rebuild kit I got was a Thomas product in it's original packaging.

Re: aux air compressor comparison

Reply #6
Yes, I was the member who called back  to Zoro to inquire about the correct number and was told the correct number was about $80.+ more for the major build kit. Apparently not really under the special price offering the time?? Buy the line, buy the whole bit. Sounds pretty profitable to me - kind of like grab your ankles.
On the forum recently, differing opinions were posted as to whether the original offered special item was OK for our Thompson pumps or not.
Jim

2002 U320
Jim Frerichs
2002 U320 42'