New H/F compressor model 67847 wont stop running

by Marc Carraway
(Lexington, SC)

New H/F compressor(67847)wont stop running, Gets to about 90psi, stays running

I got a HF air compressor the other day, the 67847 model, 2.5 HP, 21 gal, 125 psi.

Its the upright black oil black one.

Well, I get it home, ran it with compressor oil for 30 mins, drained, replaced oil, started using it. Worked great. Would kick on when it got too low and shut off when it got to the desired psi. I probably used it an hour or so by day 3.

The 3rd day during use it had drained below the psi that makes it kick on by itself, tried to fill itself back up, but it never stopped running. The pressure gets to about 90 on both of the gauges. 91 or 92 maybe at the most.

But it just runs and runs without ever shutting off by itself like it did at first.

Again, its only like 3 days old.

I wonder if the pressure switch is bad or I also read there was a pressure something internally that I'm not supposed to ever shange or mess with. Thats fine with me. I just dont know enough about an air compressor yet to know what to do 1st, 2nd, 3rd and so on.

Troubleshooting would be fine with me if I knew where to start. Anybody know anything that I should do or have any ideas for help? Thanks!!
Marc, see the troubleshooting section on the sitemap page for a link to a page about why air compressors run and run but don't build pressure.

However, I would suspect a valve or gasket failure, and at 3 days old, if it were mine, I'd take it back and ask for a new one.


Comments for New H/F compressor model 67847 wont stop running

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Oct 15, 2014
Compressor reed valves
by: Bill

For what it's worth, others have used the old valves as templates, and cut out new ones using the blade from a scraper as the raw material.

Those that did so reported good success.

They placed the scraper blade between two slabs of wood and put the stencil of the old valve on the wood and used it as the pattern.

The wood stopped the metal from vibrating as it was cut.

Oct 15, 2014
Broken reed valve(s)
by: Anonymous

Mine just quit too with the same symptom... 90psi and won't stop... We need replacement reed valves (or whatever they are called; one of mine broke in half) -- part 11 (x2) in diagram at

Remove the 4 bolts on the head, lift it and you will find an aluminum gasket and 2 reed valves.

They are just spring steel plates 0.40"x1.85", 0.010" thick.

Trying to locate a source right now...

Feb 02, 2014
I gambled and bought it scratch/dent with no returns or warranty. (not to bright)
by: marc carraway

Yes sir, and I would take it back in a split second just like you said but I messed up and gambled, probably only to lose. Theres no warranty or returns because its a no return/refund deal. Im stupid, at least right now thats what I'm thinking here.

So you all think its a valve or gasket issue so far based on the info I gave you?

What about this last I got and I'll try to not bother you all too much. Its got a dent at the top of the pressure gauge that sits right next to the dial that you regulate the pressure with. Not the gauge towards the front. And the dent is small but I'm sure it was dropped or bumped on something kind of hard. Could that gauge cause it to do this not stopping issue maybe?

Or could it being hit right there have caused something else that I'm not thinking of?

I've read and scoured the troubleshoot links on this ex site and will be trying some of the things it tells me to try as soon as daylight hits tomorrow. thanks for help so far, a lot!
The gauges display the pressure setting of the regulator or the pressure in the tank.

Neither has any impact on the production of compressed air in the compressor tank.

On the troubleshooting pages there are suggestions about some checks that can do to help diagnose the problem.

That you acquired it in a scratch/dent sale would suggest that it's fairly new, and as such, parts should be available. Do a browser search for "parts for compressor XXXXXXX" and put your compressor name and model number where the X's are.

Good luck.


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