# Melben Compressor



## toncapone41 (Nov 17, 2021)

I have an old Melben compressor. Does anyone know what part that is in the first pic that's broken?


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## iowagold (Jan 22, 2020)

from another forum
looks like ch bought them?
"Would Campbell Hausfeld help with information and parts for your Melben air compressor? Perhaps. If you are in the U.S.A., try them at: 800-543-6400, Mon Fri, 8 a.m. – 5 p.m. EST. Lack of information on Melben air compressors is a problem for owners."
with that said also mitm gasoline compressors use a valve like that for the pressure sense
and is tied in to the gasoline engine for rpm drop down to a lower idle mode.
it sort of free wheels the compressor till it calls for more pressure.

remove it strip it down if there are no plastic seats on the internals of the valve just weld or braise a nipple back on to repair what you have broken.
something hit the compressor to damage it.
maybe look at a guard for that side that is mounted only to the pump and motor base.
do not weld on the tank


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## stevon (Mar 5, 2019)

toncapone41,

That part is your idler control valve, without that working you could have a dangerous over pressure issue in the tank! the part "unloads" the cylinder head letting the motor run without putting further pressure in the tank. Make sure you get an unloader for a gas compressor. Grainger should be able to help you

Stephen


toncapone41 said:


> I have an old Melben compressor. Does anyone know what part that is in the first pic that's broken?


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## stevon (Mar 5, 2019)

toncapone41,

You need something like this:










Stephen



https://www.grainger.com/product/55RU22?ef_id=Cj0KCQjwnNyUBhCZARIsAI9AYlHKo45TVbwKVyVkPRXti63x6JbL6gBZYG3alkE4Dv3YpAcjxE_uZGQaAglTEALw_wcB:G:s&s_kwcid=AL!2966!3!496359977260!!!g!1664546720524!&gucid=N:N:PS:Paid:GGL:CSM-2295:4P7A1P:20501231&gclid=Cj0KCQjwnNyUBhCZARIsAI9AYlHKo45TVbwKVyVkPRXti63x6JbL6gBZYG3alkE4Dv3YpAcjxE_uZGQaAglTEALw_wcB&gclsrc=aw.ds





stevon said:


> toncapone41,
> 
> That part is your idler control valve, without that working you could have a dangerous over pressure issue in the tank! the part "unloads" the cylinder head letting the motor run without putting further pressure in the tank. Make sure you get an unloader for a gas compressor. Grainger should be able to help you
> 
> Stephen


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## MacMcMacmac (9 mo ago)

Melben is the tank manufacturer. This pump was used by Coleman/Powermate. The original part is a pilot unloader valve and was doing nothing in it's original installation. It's supposed to send a signal to head unloaders to open the inlet valves so the compressor can freewheel without pumping. All is was doing was sending high pressure air right back to the discharge valves. Steve shows the correct part, but you will still need a bull whip throttle control cable if you want to idle down the motor


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## stevon (Mar 5, 2019)

MacMcMacmac,

I do not have the original part number or access to a parts list. I only showed an example of what I am talking about. You have it correct that a throttle control cable is not in my example, thanks for the catch! maybe Grainger can help him at the counter with a usable replacement part.

Stephen



MacMcMacmac said:


> Melben is the tank manufacturer. This pump was used by Coleman/Powermate. The original part is a pilot unloader valve and was doing nothing in it's original installation. It's supposed to send a signal to head unloaders to open the inlet valves so the compressor can freewheel without pumping. All is was doing was sending high pressure air right back to the discharge valves. Steve shows the correct part, but you will still need a bull whip throttle control cable if you want to idle down the motor


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