• Thankful For Your Family…. Business?
    Landscaping businesses are often family endeavors. While this can combine the best of both worlds (personal and professional), it isn’t always smooth sailing. Click here to read more.

hypro pump d 403 grgi

phillie

LawnSite Senior Member
Location
indianapolis, in
Hey guys, I just put new diaphragms in and replaced some o-rings today.The manual says to recharge the pump with 20% air of normal operating psi. I cannot find the valve stem. Anyone know where it is? This pump is a couple years old but its new to me. I've been checking the manual and cant find it anywhere. Thanks.
 

MowerMedic77

LawnSite Bronze Member
The D403 is a 3 piston pump with no dampener so no air bladder to fill like the older 2 piston style pumps like the D-30 or D-252 these units had a red dome with a valve stem to add air. Be sure to refill with hypro oil or 30wt non-detergent oil. Hope this help :)
 

MowerMedic77

LawnSite Bronze Member
OP
phillie

phillie

LawnSite Senior Member
Location
indianapolis, in
That is a good question. I bought the lesco space saver off of a guy who went out of business and had it sitting in his shed since the end of last season. I dont want to statr it up yet do to the cold weather as i have been storing it in a shed also. The guy said its leaking from the pump seal so I bought a rebuild kit. The kit came with alot of o-rings, valves and diaphragms. I dont think it came with a pump seal unless its just a big o-ring. The manual doesnt explain a pump seal.
 

MowerMedic77

LawnSite Bronze Member
If your not seeing oil on the outside of the unit then he may have only been referring to the diaphragms themselves. What color is the oil in the fill glass or sight glass? If it is milky in color then the pump oil has mixed with the chemical he was spraying. If you don't already have here is the parts breakdown for your pump
http://www.hypropumps.com/FileAttachments/Spray/en-us/9910-D303_D303GRGI_D403_D403GRGI_pd_03-08.pdf

This is not the easiest of the Hypro pumps to rebuild all the o-rings make it more of a pain then anything. The three large diaphragms are pretty straight forward but the O-ring kit has alot of different sizes some of which you will not even use. I usually spent more time matching up and fitting them into the groves so they didn't get pinched during reassembly then any other part of the rebuild. Do yourself a favor and only tear apart one piston/head at a time and remove and match each o-ring as you find them. Good luck and keep us posted :)
 
OP
phillie

phillie

LawnSite Senior Member
Location
indianapolis, in
The diaphragms I replaced looked good, no cracks or anything. All the o-rings looked good too. It is rediculous how many o-rings there are. When I bought it the oil was drained. It still doesnt have any oil in it. I cant really find out without filling it up and running it huh? Im guessing that it was leaking to the outside of the pump but obviously Im not sure. That parts breakdown is the one I've been using from the manual. I still have never started it up because of the weather, Im afraid of doing more damage. I dont think he blew the lines out to and from the tank. I think that I am going to take off the gear reducer and replace the flat gasket(#20 in parts breakdown) between it and the pump. After that Im outta ideas.:confused: If that gasket is bad do you think it would leak oil. Thanks for the help.
 

MowerMedic77

LawnSite Bronze Member
I think that I am going to take off the gear reducer and replace the flat gasket(#20 in parts breakdown) between it and the pump. After that Im outta ideas.:confused: If that gasket is bad do you think it would leak oil. Thanks for the help.
Yes it can leak from there but more common is people over fill the gear reduction and it vents out from the fill cap. Your space saver is three separate components the engine, gear reduction, and pump and all three take different oils and they don't mix. When you pull the fill cap from the gear reduction it should look like a tube with a bump or nub on the end this is the fill line. Fill the assembly with 80w90 gear oil up to that nub(screwed in not just resting on the threads) if you go over when the unit is running it will vent out of the top. If it does vent its not a bad thing will just make a mess but will stop once it gets to the correct level.
 
OP
phillie

phillie

LawnSite Senior Member
Location
indianapolis, in
Thanks that helps alot. The only reason I thought it was leaking from there is that there is a red line of what looks like that liquid seal stuff there. Im told that it could be from the factory though. I thought he was trying to repair the leak with it. Its snowing here again today. Hopefully at some point the weather will help me out so I can fill it up and run it to see where its leaking. I should have asked these questions when I bought it but he seemed clueless as far as lawn care is concerned so I stopped asking questions. I bought the whole unit for a grand so as long as I can get it working then it was a good deal. What do you think he could have meant by saying pump seal? Also once I remove the gear reducer I have to replace that gasket dont I? You been a big help I appreciate you taking the time to help.
 

MowerMedic77

LawnSite Bronze Member
What do you think he could have meant by saying pump seal? Also once I remove the gear reducer I have to replace that gasket dont I? You been a big help I appreciate you taking the time to help.
I have no idea what he meant by pump seal, I have heard so many things described as one thing by a customer over the phone and when they get to the shop its something completely different. So like I tell them without seeing it for myself its hard to say what it is.

As far as the gear reduction goes I have separated before and the gasket was fine and reusable with a light coat of this stuff http://www.permatex.com/products/Au...tex_Aviation_Form-A-Gasket_No_3_Sealant_a.htm

And its been my pleasure, actually have not been on the site for a while so this has been fun for me :)
 
Top