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boxxer421 pump issue

wandwizard

Randy Dockins
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My best guess is you have a check valve issue in your pump. I would disconnect the line from the pump going to the unloader and bucket test to see if you're getting 3.5 gpm. The test should be pretty accurate. Run at full throttle for exactly one minute. It looks like you may have good pressure. Does it still adjust all the way up to 1,000 psi? Is the pump very old?
 

jamesNY

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thank you so much Randy, this is a brand new pump, old 13 years pump has a same issue, thought something wrong with it, just changed it few days ago, but new pump still has same issue. no problem going to 1000psi.
Open the pressure valve,its down to 250psi, but you can see, Pressure will down to 0 psi in a very short time and back to 250 psi. Any suggestions, thank you.
 

jamesNY

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My best guess is you have a check valve issue in your pump. I would disconnect the line from the pump going to the unloader and bucket test to see if you're getting 3.5 gpm. The test should be pretty accurate. Run at full throttle for exactly one minute. It looks like you may have good pressure. Does it still adjust all the way up to 1,000 psi? Is the pump very old?
thank you so much Randy ,please see my new post.
 

wandwizard

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The only thing I can think of that might cause that is the unloader. Have you checked to see that your water box is filling correctly and not bottoming out? If you're certain water is getting into the machine just fine I can only suspect your unloader is the problem. Have you ever put on a new unloader? I really don't know of any other thing that can cause what I saw in your video with a new pump.

Btw, if you have put a new unloader on it and bought it somewhere other than a TM dealer there is a check valve that must be removed from it before it will work right. Believe me, I found this out the HARD WAY!!! I made a post about this and show the check valve. It could also be you just need a new unloader. I think my first one lasted maybe 8 or 9 years before it crapped out. It started with a loss of pressure and then soon got to no pressure at all.
 
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jamesNY

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The only thing I can think of that might cause that is the unloader. Have you checked to see that your water box is filling correctly and not bottoming out? If you're certain water is getting into the machine just fine I can only suspect your unloader is the problem. Have you ever put on a new unloader? I really don't know of any other thing that can cause what I saw in your video with a new pump.

Btw, if you have put a new unloader on it and bought it somewhere other than a TM dealer there is a check valve that must be removed from it before it will work right. Believe me, I found this out the HARD WAY!!! I made a post about this and show the check valve. It could also be you just need a new unloader. I think my first one lasted maybe 8 or 9 years before it crapped out. It started with a loss of pressure and then soon got to no pressure at all.
thank you, the water box filling is very correctly. the unloader is original one. so, that is mean i need new one for it?
 

jamesNY

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The only thing I can think of that might cause that is the unloader. Have you checked to see that your water box is filling correctly and not bottoming out? If you're certain water is getting into the machine just fine I can only suspect your unloader is the problem. Have you ever put on a new unloader? I really don't know of any other thing that can cause what I saw in your video with a new pump.

Btw, if you have put a new unloader on it and bought it somewhere other than a TM dealer there is a check valve that must be removed from it before it will work right. Believe me, I found this out the HARD WAY!!! I made a post about this and show the check valve. It could also be you just need a new unloader. I think my first one lasted maybe 8 or 9 years before it crapped out. It started with a loss of pressure and then soon got to no pressure at all.
this one?
 

wandwizard

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thank you, the water box filling is very correctly. the unloader is original one. so, that is mean i need new one for it?
Yes, that would be my guess. I know of no other way your pressure could possibly drop that much especially with a new pump. I would still do a bucket test if you haven't already, but I suspect nothing at all is wrong with your pump. The bucket test is fairly quick and easy. If the pump is putting out the stated 3.5 gpm then it has to be something with the machine causing the drop in pressure. I know of no other thing on a Boxxer that can cause that kind of drop. Even the Dema solenoid only causes a slight drop when it gets activated, but only maybe 100 psi.

Here is the post I made about the check valve. https://www.truckmountforums.com/th...bably-some-other-hydramaster-machines.130259/
 

wandwizard

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Yes that's it. That is about 4 times the retail price. If you need it right away you can order it. The check valve should already be removed from it. I think Hydramaster removes them before they send them to Jondon. Unless you're in a quick driving distance from Jondon I suggest you order from Watercannon.com. Nearly 1/4'th the price. You must remove the check valve mentioned above to make it work. Takes just a few minutes to do that. Water cannon has excellent customer service and got mine to me pretty quickly. You can very nearly buy 4 of them for Jondons price.
https://www.watercannon.com/product/4690/unloader-with-bypass-handle-mg4000-1500-psi-yellow-180296
 
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jamesNY

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Yes that's it. That is about 4 times the retail price. If you need it right away you can order it. The check valve should already be removed from it. I think Hydramaster removes them before they send them to Jondon. Unless you're in a quick driving distance from Jondon I suggest you order from Watercannon.com. Nearly 1/4'th the price. You must remove the check valve mentioned above to make it work. Takes just a few minutes to do that. Water cannon has excellent customer service and got mine to me pretty quickly. You can very nearly buy 4 of them for Jondons price.
https://www.watercannon.com/product/4690/unloader-with-bypass-handle-mg4000-1500-psi-yellow-180296
Very grateful for your help,just got one from watercannon. have a great day.
 
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wandwizard

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Very grateful for your help,just got one from watercannon. have a great day.
I'm glad I could help. I suggest you remove that check valve as soon as you get it. I also suggest you use your phone and take a picture of your old unloader either before or after you remove it. It can get a little confusing putting that thing back together. Here is the one I took when replacing mine. It should help get it together easier.

20190529_140433.jpg
 

jamesNY

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I'm glad I could help. I suggest you remove that check valve as soon as you get it. I also suggest you use your phone and take a picture of your old unloader either before or after you remove it. It can get a little confusing putting that thing back together. Here is the one I took when replacing mine. It should help get it together easier.

View attachment 90033
After changed it, everything working great, thank you Randy and take care.
 

jamesNY

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After changed it, everything working great, thank you Randy and take care.
everything going great until today, same issue happened, setting psi to 400, start solution out. drop psi to 350. but you can see, pressure very not stable, after about 3 seconds, pressure keep vibrate, keep solution out ,and after 10 seconds, pressure back to normal ( 350psi keep solution out)
 

jamesNY

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I'm glad I could help. I suggest you remove that check valve as soon as you get it. I also suggest you use your phone and take a picture of your old unloader either before or after you remove it. It can get a little confusing putting that thing back together. Here is the one I took when replacing mine. It should help get it together easier.

View attachment 90033
and this is the water box same time.
 

wandwizard

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When it drops from 400 to 350 were you triggering your wand? If so, that would be a normal drop. When it dropped lower I'm not certain what happened unless your Dema solenoid got hot enough that it opened up and was letting very hot water into the waste tank.

It looks like from your second video that the water inside your water box was getting to around boiling temperature and that is definitely not normal. I think the only times I've seen that happen was when my thermal relief valve was either bad or clogged up. I would also make sure and check your orifices and make sure one of them isn't clogged. If the top orifice on the front of the machine gets clogged your machine will overheat rapidly and shut down. I'm not certain that's the problem, but you need to figure it out quick. You shouldn't run it like that or you will be buying another pump soon.

DO YOU RUN A WATER SOFTENER?
 

wandwizard

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Also, have you put on a new thermal relief valve? I'm suspecting you have a problem with it and that the water in your water box is getting to boiling temperature sending boiling hot water through your pump.
 

jamesNY

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jamesNY

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James chung
When it drops from 400 to 350 were you triggering your wand? If so, that would be a normal drop. When it dropped lower I'm not certain what happened unless your Dema solenoid got hot enough that it opened up and was letting very hot water into the waste tank.

It looks like from your second video that the water inside your water box was getting to around boiling temperature and that is definitely not normal. I think the only times I've seen that happen was when my thermal relief valve was either bad or clogged up. I would also make sure and check your orifices and make sure one of them isn't clogged. If the top orifice on the front of the machine gets clogged your machine will overheat rapidly and shut down. I'm not certain that's the problem, but you need to figure it out quick. You shouldn't run it like that or you will be buying another pump soon.

DO YOU RUN A WATER SOFTENER?
(When it drops from 400 to 350 were you triggering your wand? ) answer is yes, do you think water touching the boiling temperature? temperature meter said only 160 degree.
and how do i check orifices and make sure one of them isn't clogged. ?? thank you. and i just did a descaling few days ago.