Pulsing while pulling trigger

KGILL

New member
My pressure pro 5.6 gpm 2500 psi cold portable is pulsing when I pull the trigger. I noticed this last week when I was not hooked up to a supply tank and figured it was a supply issue. I hooked up to a 65 gallon supply and still getting the pulsing when I pull the trigger. I have looked at the check valves and they appear fine, so do the o-rings. The oil is not milky but I am changing it because it needs to be done anyway. I am also replacing the air filter. Any suggestions? Russ Johnson, I know you gave me a couple of possibilities on Friday but I have had a lot on my plate and was not able to get to fixing my pressure washer till now. Unfortunately I failed to write anything you said down and I have forgotten what you told me.
 
Air leak, or a really trashed seal on one plunger. Tighten the fittings, or you can run a hose over the fittings as the machine is running, and make sure it is not one of them.
 
I'd say torn high pressure seal, especially if it behaves the same whether suction or pressure fed.
 
a great "quick test" you can do..
Pressureize the inlet side of th pump, with a garden hose..
you're looking for water coming out from under the head, if its your seals.
..but if you see no leak elsewhere, and the pressure pulsation doesn't go away..
a high-pressure seal, or an o-ring under a check valve could be the cause.

This is a reminder..
People who plumb their tank-fed system to EASILY be "pressure-fed" for quick testing,
can troubleshoot "rings around" their competition.

..another exerpt in my TroubleShooting and BulletProofing class.
 
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Russ, do you mean the high pressure seals for the packing? If so, can they be purchased separate or do I need to buy a whole new packing?

Yes, the high pressure seal is the brown packing. I'd replace them as a set if one needs replacing.
 
Also to all the above check to make sure your belts are tight and in good shape, one of our machines was doing this caused by the belt being worn and it was slipping causing it to loose pressure for a second!
 
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