# snoway plow dp question plz help



## GTCPW (Feb 19, 2011)

hey, i'm new to this so plz excuse my ignorance, i recently bought a snoway blade
25D105636 off a friend, dp used to work but now it won't, everything else works fine
i checked the 4 way valve powers up and moves (magnetic) and the motor runs, but the plow lifts when dp is turned on, and down is pressed...i don't know how to test the pressure switch, the control box wiring is right as i have poured over all the manuals known to man, anybody else ever encounter thios problem?


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## GTCPW (Feb 19, 2011)

anyone got any ideas??


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## Schnabel Plowin (Feb 14, 2010)

When I had that problem with my 25, it was a corroded and loose wire coming out of the dp valve. It may need a new coil in it.


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## Dlongerman (Nov 6, 2008)

post this in the Snow-Way forum you will get a better response! welcome to plowsite!


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## basher (Nov 13, 2004)

Check and be sure the jack switch is in the proper configuration and all the wires connected under the pump cover. It sounds like the DP valve is not responding. Here are you Owners manuual, parts manual and a troubleshooting/mechanic's guide.

Fenner repair
http://www.snoway.com/service/Fenner Repair/97100036A.pdf

25 parts
http://www.snoway.com/service/Parts Manuals/97100204j.pdf

25 owners manual
http://www.snoway.com/service/Owner Manuals/97100203E.pdf


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## Schnabel Plowin (Feb 14, 2010)

Dlongerman;1247039 said:


> post this in the Snow-Way forum you will get a better response! welcome to plowsite!


There isn't one.


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## winged1dur (Feb 12, 2006)

Dlongerman;1247039 said:


> post this in the Snow-Way forum you will get a better response! welcome to plowsite!


:laughing:


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## GTCPW (Feb 19, 2011)

i assume by snow way forum you men join the group snoway owners


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## GTCPW (Feb 19, 2011)

wires all semm good, dp valve is working, the moving peice goes up when magnet is powered and drops down when no power....confused, how does the dp pressure switch work???


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## Schnabel Plowin (Feb 14, 2010)

GTCPW;1247616 said:


> wires all semm good, dp valve is working, the moving peice goes up when magnet is powered and drops down when no power....confused, how does the dp pressure switch work???


The red light on the controller is lighting up, right?


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## basher (Nov 13, 2004)

Do you have a jack switch? are you sure the down pressure coil is getting 12 volts when you turn the down pressure on?


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## GTCPW (Feb 19, 2011)

jack switch? must be for a jack leg i assume, dont have a jack leg. yup coil getting 12 volts and valve moving freely and light is turning on when dp turned on and down is pressed


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## basher (Nov 13, 2004)

are you testing the valve with the coil or by hand? could be a bad coil, but it has to be the 4way valve that is the issue. Are you sure the coil is good? the valve could be stuck partly shifted and is not closing properly. Does it lower with out the DP on?

I sent you the Gravity owners manual here is the Dp manual

http://www.snoway.com/service/Owner Manuals/97100200E.pdf

These are available on the Snoway site.


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## GTCPW (Feb 19, 2011)

tried the dp valve with the coil and by hand, not sticking that i can tell, even took it an laid in on my heater vent fo 1/2 hour to see if there may be ice in it, but no change, seems perfect, without dp on it lowers fine, and everything else works fine.......can't figure it out. how does the dp pressure switch work? i know it makes the blade adjust to the surface being plowed, but how?


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## basher (Nov 13, 2004)

From the owner's manual


Down Pressure (DP) System 
The Down Pressure (DP) System consists of two 
separate but interactive electrical circuits, both controlled 
by the DP Toggle Switch. 
• 4-Way Valve - Controls fluid flow to and from the Raise 
Cylinder and establishes either a float or DP 
condition. 
• DP Pressure Switch - a pressure sensitive ON switch 
that controls the pressure available to the DP 
system by limiting the Motor run time in the DP 
mode. 
Electrical current is provided to the DP Toggle Switch 
center terminals (common) through the 14 Pnk wires from 
the Raise/Lower Switch "lower" terminals. The 
Raise/Lower Switch must be in the Lower position for the 
DP to be activated. The Raise/Lower Switch receives 
power through the 9 RED/BLK wire, any time the vehicle 
key switch is in the ACC or RUN position. 
Positioning the DP Toggle Switch to ON supplies power to 
the Indicator Light, and allows current to flow, through 11 
Blue wire, to the Four-way Valve. Current also flows from 
the DP Toggle Switch, through 12 Yellow wire, and 
supplies power to the Pressure Switch. 
• The 4-Way Valve, when energized, directs fluid flow to 
the rod end of the Raise Cylinder creating pressure 
in the Raise Cylinder and forcing the plow down. 
When the 4-Way Valve is de-energized (Down 
Pressure Toggle Switch in the OFF position) a 
spring returns the 4-Way valve to a open port 
position that opens all ports in the Raise Cylinder 
allowing the blade to float and follow the contour of 
the ground. 
• The DP Pressure Switch senses hydraulic pressure in 
the rod end circuit of the Raise Cylinder. When 
pressure falls below the Pressure Switch preset, the 
Pressure Switch closes and current is supplied, 
through 14 Tan wire, to activate the Motor Solenoid 
allowing the 12VDC Motor and Hydraulic Pump to 
create hydraulic pressure which is supplied to the 
rod end of the Raise Cylinder. When pressure 
increases the pressure switch opens and stops 
current flow to the Motor Solenoid which disrupts 
power to the 12VDC Motor. 
The down pressure system is protected by the DP Relief 
Valve. If, while in the DP mode, a obstacle is encountered 
forcing the blade up excess pressure will be created in the 
rod end of the Raise Cylinder. This excess pressure is 
relived to the sump by the DP Relief Valve. Once the 
obstacle is cleared the plow will lower back to the surface 
being plowed, lowering Raise Cylinder pressure, and the 
Pressure Switch will then close re-establishing correct DP 
system pressure. 
The down pressure system will be over ridden when the 
toggle switch is placed in raise, but will resume when 
placed back into float position.


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## GTCPW (Feb 19, 2011)

ok so basically the dp pressure switch CANNOT cause the problem i'm having, but the valve and coil seem ok...how much should the valve move, put power to it and moves *about* 1/4 inch up inside, take power and instantly comes back down....valvebody dirty?, or is there a check valve or something sticky? think i will try flushing the system again


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## basher (Nov 13, 2004)

Correct, why I never mentioned the hydraulic DP switch. The jack control switch or the control box switch COULD cause the issue but you stated the coil was receiving proper power at the proper time.

Your issue is caused by a LACK of response from the DP valve not allowing the fluid to divert to the down side of the two way ram. Clean and flush all you want but the issue is the valve. 

If you use the owners manual and check the 12 volt path to make sure all the coils are being properly energized at the proper time then there is nothing left but the valve as it just diverts the raise function to a lower function


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## GTCPW (Feb 19, 2011)

ok, sorry if i sounded stubborn but the valve is moving so i assumed it was moving enough, i'll have to go and buy a new one i guess, 3hr drive for parts i didn't want to go there and buy the wrong parts, is the valve sold seperate from the coil normally or package deal? doesnt really matter, just as well to have both i guess either could be problematic


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## basher (Nov 13, 2004)

I understand and there could be something I'm not "seeing" remote diagnostics is difficult but the cause of your problem is the lift system is not diverting and if you have exhausted all the electric possibilities that leaves only the valve


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## GTCPW (Feb 19, 2011)

yeah you're right, i mostly didn't understand how the dp pressure switch worked, i was thinking that somehow it was connected to making the actual downpressure, i read manual but it didn't click until you posted it....jeez i feel dumb...LOL


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