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sarowe

Pump Question

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Hello Gang

4 GPM pump

4000 psi

3.5 Nozzle

Installed a pressure guage to check pressure because it seemed kind of weak. Had a leak on the hose reel packing gland and got that repaired thinking that was a problem. Pump oil level is fine. Water filter from tank is now clean. Belts (2) were checked and are nice and tight.

I show 4000 psi without flowing water but only 1800 when flowing. Does this sound like its not loading up when under a load? Any ideals?

Thanks in advance. Love the site by the way.

Steve

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I show 4000 psi without flowing water but only 1800 when flowing. Does this sound like its not loading up when under a load? Any ideals?

Steve

You are measuring static pressure, which is really only valid when there is no water flowing. Your pump is capable of compressing the system to 4000 psi until a valve is released. The properties of the valve determine the amount of back pressure you experience. The reason for your drop to 1800 psi is because the water is not only pushing on your gauge but also pushing through the orifice; the larger the orifice, the lower back pressure you will measure. Alternatively, the smaller the nozzle, the higher the back pressure. So, if you are showing 4000 psi at a no flow condition, i'd say your pump is performing properly. The 1800 is purely dependent upon your orifice type and some other minor factors if you are measuring near your nozzle.

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Your tip could be as large as a 4 according to the standard tip chart so I do not think that is your problem. It almost sounds like your packings are a bit worn. If you are getting any cavitation (vibration in the line) this is more than likely your problem. Try to pressure feed your pumpdirect from a hose. If your packings are worn you will see water leak from between the head and crank case. This will also tell you if you are starving the pump of water which may also cause your pressure loss. If it works fine after pressure feeding the pump and there ar no leaks make sure that you have no obstructions in your line from the tank or your ball valve isn't partially closed. Otherwise it cluld be a whole bunch of other things. If you like you can call me tommorw and I will be happy to help you trouble shoot it.

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Thanks Paul and Ryan. Sounds like Ryan you seem to feel like there is no problem while Paul you think that I just might have a problem with first checking the supply water for a restriction. There is no restriction that I see but tomorrow I'm going to feed directly from the city water tap instead of the tank to see what that does. Paul, if that doesn't show me something then I will call you. Also, I think I'm going to do a flow check tommorow also (GPM). Thanks for the help gentlemen.

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Had a similar problem myself.... I lost 1300 PSI.

Read this:

http://forums.thegrimescene.com/showthread.php?t=6504

yea, but I failed to see what problem was and how ya fixed it..

Sarowe,

Did this problem start all of a sudden?

When I had similar problems all of a sudden it was not unloader or nozzle clogging or sizing or the like at all...

One time I sucked in some saran wrap in my float tank. The sound pitch of the whole engine setup sorta changed due to starvation and there was hose chatter.. (don't ask..lol).

The other time was very similar to that time in symptom but I lost more pressure (about 1/3 of system pressure) and there was no hose chatter. There was a change in sound pitch almost same akin to starvation and I had full pressure when not pulling trigger. Everything seemed smooth and fine but no pressure over 2200 pressure when pulling trigger... same as yer description--

I show 4000 psi without flowing water but only 1800 when flowing. Does this sound like its not loading up when under a load? Any ideals?

Turned out thissecond time I was running on one engine cylinder with a broken connecting rod cap bolts. Engine sounded fine at idle or full rev but when I put it under load there was just no horsepower. It was like yes pump could build pressure on static situation to my 3k psi but trying to actually move water was another story.... You can check such by unplugging a spark plug to see if there is a change..(there should be a change even if ever so slight)...just a thought anyways if ya got a twin engine..

You should do what Alan said in that Grizzley thread about testing head pressure without hinderances like unloader, coil , or injectors right off the pump outlet if the above doesn't apply. You have to wire your gun trigger on at all times while engine is running to prevent things from blowing up though as that is what the unloader is for!...I wire the whole wand to side of trailer while doing this so I can concentrate on adjusting things.

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Ok. Here is where I'm at now. Ran water directly to pump bypassing the tank. Pressure went from 1800 to 2000 when flowing water. Also, engine is running fine. No problem there. Still seems that I should get more than that. There is just not much kick from the lance. Not like when I bought the machine about 6 months ago. I do have a water leak although very very small from the high pressure relief valve on side of pump. Maybe that is it.

Funny thing is that this pump will build pressure to 4000 but only 2000 when flowing water. Any more suggestions? Unloader? Packing Glands.

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I took off the head to inspect the packing glands. Going to go ahead and replace these.

Also, I want to run my bypass on the unloader straight back to the tank as everyone reccomends. My unloader is 2 pieces with the outlet of the bypass joined to the inlet with a 1/2 inch pipe with an o ring on it.

Cant I just plugged the inlet with a male threaded plug and run a hose off the unloader bypass? Want kind of pressure is this? Thanks.

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On the previous reply what I meant was not to plug the inlet of course as this is for the water supply. Wont get a whole lot of pressure with that now would I. LOL.

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This thread gets my goat as it hits way too close to home a few times..

Would like some expert advice for Sarowe as well as myself on the following 3 ideas. Wondering if any of them can be discounted or validated as playing a part:

Is there something about a flow situation versus a no flow situation through a pump that can change it's ability to pressurize or not? This packing thing and what Paul says has me wondering...

How about the unloader.. Can and does only the flow type unloader gone bad or misadjusted present itself like problem in this thread?

(think I changed out my cat flow type to a pressure type when if wouldn't let me up under flow)

A pump turning with proper rpm and horsepower that makes pressure while static one moment then doesn't the next under flow surely must be a situation of more going out via too big a orifice (nozzle,leak) than getting in (starvation)?

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Replace the high pressure relief valve on the pump, that will help some. From the way you are describing the problem it sounds like one of two things, your unloader went bad or your packings wore out. If you have been running your pump in extended periods of bypass, more than 2 min at a time I would guess that you wore out the packings.

Have you tried to run the pump open gun for testing? Remove the unloader and crimp off the bypass (if connected to the inlet) connect your pressure hose and gauge to the outlet of the pump, LOCK THE TRIGGER OPEN, and start the pump, while holding on to the gun.

If your pressure is fine you have a miss-adjusted or worn out unloader. If the pressure is low your packings are worn and need to be replaced.

You may also have some debris stuck in the check valves which is causing one or more to not seat properly or a crack in one of the ceramic pistons may cause the loss as well. This type of situation will usually cause a vibration or cavitation in the pressure line which you can feel, but still check them.

When you run the bypass hose to the tank you will do it like you said, remove the hose from the unloader, plug the inlet wher the bypass hose was attached and run a new hose from the unloader to the tank. As far a pressures are concerned it will vary based on the type of unloader you have, flow unloaders will have a higher spike of pressure than a trap but once in bypass the pressure is minimal. What I would reccommend is to use an old section of pressure hose, and the 3/8 fitting on the end will screw right into your unloader bypass.

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Kevin,

A mis-adjusted unloader can give you this type of problem, as an unloader wears they can do many strange things. That is why if you are having a problem with a pump you shoud try a few things before replacing parts. I have been a little all over the board on my trouble shooting but it is difficult to give advice with little info. Plus I am typically that 1% guy, the stuff that no one has ever seen happen before happens to me so that is usually my first response to people. That being said here is the progression that I use for trouble shooting.

1. Is the tip worn or clogged?

2. Is the gun clogged?

3. Is the chemical injector partially or fully blocked (downstream, my 1%er)

4. Is the hose blown or is there a leak somewhere?

5. Is there water?

6. Is the motor running ok?

Testing:

Pressure feed pump- Pressure ok, Problem=water supply problem, packings(look for dripping water behind head of pump)

Pressure not ok, try testing open gun

Open gun test- Pressure ok, Problem=unloader

Pressure not ok, Problem=packings/check valves rebuild pump

While these or not the only problems and soultuons they are the most common, if you ever have a 1% problem I will share my experiences with you as well.

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..had the 1% downstreamer clog too awhile back also and I broke it completely with only a quik dunk in hydrochloric...

Paul..yer bad luck!!......Now I need packings darnit as I developed the head leak you were talking about just today while in process of rebuilding and spraying off my coil. Took my head off and I got some sqwished and torn seal material. Still got about 2700psi and can feel the loss of kick and there is hose chatter...It's actually been breaking and fixing itself off and on for a month now soit not yer fault, lol.

All my 1%'s add up to almost a new machine...:lgsick:

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Cavitation is caused by air in the pump, whether a piston pump like our pressure washers, or a vane pump like on a fire truck. Air can be sucked in the inlet side by a leaky hose. I use 3/4 inch rubber heater hose because it is more forgiving to crushing by my trash cans. But if you use clear hose, you might be able to see the bubbles. Try replacing the intake hose, using good gear drive hose clamps. You might have an air leak at the fittings. I had an occasion where I had no outlet pressure. I called an un-named source in Texas. He told me what I just told you, I knew he was just blowing me off. After 2 hours of tighting clamps, filling the system w/air and generally just wasting time, I replaced the hose. Of course Larry was right. The hose was the problem.

When a pump cavitates, the air bubbles can ruin a pump quickly. The water cools the packing and ceramic pistons. Air allows the heat to build to a temperature that destroys the packing and pistons. The ceramic pistions can develop very small cracks that expand when hot, allowing the water to leak. I have not had much sucess rebuilding pumps. Now I just keep a spare pump on hand. You may be able to find a rebuilt pump from that guy in Texas, or the Wizard. I have tried other brands, but find the General TS 2021 works for me.

Does water leak from the mating joint between the valve head and the crankcase? Or does the water leak from the bottom of the crankcase. This may be an indication of the pistons leaking.

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Thanks Paul and to all who have had input up to this point.

More troubleshooting work continues today starting with the pressure test with the unloader being bypassed.

Question. Know of a good pump parts supplier?

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I bet if we combine everyones 1% problems we could come up wit a solution for everything wierd that ever happens.

Well I am unsure now of where it is located but there is or was a very comprehensive if not exhaustive troubleshooter on one of these sites.

Maybe Delco or Hot Water Wizzard had it...Was a progressive flow type of method of going at both pumps and heat problems. Felt like John Derosa's(sp?) work though as he was putting out info's for awhle that one would only find in a service department. Anyone know what happened to him. I aint seen him involved for awhile now...

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Here is one of the ts2021 Douglas speaks of- http://cgi.ebay.com/New-General-Pump-TS2021_W0QQitemZ7628566231QQihZ017QQcategoryZ46536QQssPageNameZWD1VQQrdZ1QQcmdZViewItem

Sarowe,

Not sure if this fella is member or vendor here or not but I ran across him on Ebay recently-

Jaime Mortimer" <jaimemortimer@myco-inc.com>

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If you order the packing kit #8 it will give you the seals for all three pistons. the kid #28 with the brass is 1 per piston so you will need 3. I do sell all of the parts for those pumps as well as others, if you go to my website you can look up your specific pump and see which kits you may need. www.mobicleaninc.com

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Hello Gang

Bypassed the unloader by going straight to the wand as suggested. Pressure with trigger wired opened and me shaking in my boots climbed to 4500 psi and leveled out right there.

Ok. Sounds like a problem with the unloader. Either the unloader is bad or I'm not getting it adjusted properly. It is the same as any regulator. Correct? I have it turned in (clockwise) as far as it will go and get 2500 now. Am I missing something here? If not then I'm sure the unloader is bad.

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Try backing it off slowly and see if the pressure goes up I have run across some that work in reverse and they can be over adjusted as well. More than likely you will need a new one though. I'm glad you dont need new packings that is one less expense for you. Let me know if you need more help and feel free to call.

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Put another unloader on the pw. Set it up to bypass back to the tank. Cranked it up and guess what.

Builds pressure to 4000 psi after adjustment of regulator.

With flow through the wand and a turbojet nozzle I get 4000 psi.

With flow through the surface cleaner the pressure drops to 3200 psi. Does this indicate worn nozzles or is this normal for a surface cleaner with the 2 nozzle set up?

Awesome!! This was done with water direct from city water pressure and not the tank. Only varible left to check now but I'm sure its going to work fine now.

Many thanks to all who responded to this thread.

I come from the facilities maintnenace profession so if you have any a/c or electrical isssues at your home let me know as I think I can be somewhat of a resource for you guys and gals on this.

Thanks again!!!!

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Congrats Sarowe!

Now that Sarowe is fixed mindifI hijack thread for a second??:)

Help!.. hey Paul, Douglas, anybody.... changed my packings and I still got a one second drip between crankcase and head up underneith.

The packing kit did not come with the red plastic rings (long life rings) and but changed them as well being that one was broke. Apparently the inclusion of such makes it an older style. I did not upgrade to new style as not only did the shop say there was no need to but I would have had to replace the whole brass...

I tell ya, the new packings sure did go on tough and I had to stagger tighten the head bolts down the last half inch or so. I installed the brasses onto the pistons first and then the head that is. Is that correct way? Head went on nice and even and I got smooth pressure again with no hose chatter so am assuming I did not bind them and ruin them in any way...hoping anyway.. So now I wonder what is up.. Is my leak from the big rubber O rings. Tightening the head down would just try to hide the leak so can't imagine that be of issue...Waternot supposed to go back behind brasses right?

ps/ well no silly.. I was supposed to install packing with proper tools into the head:

post-2209-137772164962_thumb.jpg

post-2209-137772164966_thumb.jpg

post-2209-13777216497_thumb.jpg

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