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  #1  
Old 02-22-2020, 02:56 AM
randy h randy h is offline
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Default Low pressure except when return hose is crimped. What's up?

Gentlemen, I have been having troubles with annoying low pressure indications. I've replaced screen, filter, every component on the manifold except the check valve. I've back blown the wvo line. I've even replaced the wvo line and properly wrapped it with a coolant hose and insulated the pair. Finally, in desperation, I began thinking that too much wvo was returning to the wvo tank through the manigfold and down the return line to the tank, so I crimped the return hose between the manifold and the wvo tank with vice grips. That seems to have solved the low pressure problem. What's up? Thank you.
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Old 02-22-2020, 03:13 AM
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greaseguy greaseguy is offline
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Default Purge valve

When the purge valve is open fluid flows thru return line to Wvo tank
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Old 02-22-2020, 08:38 PM
randy h randy h is offline
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Thank you for the reply. Marc. I figured that is what's
happening. But how do I solve the problem other than by squeezing the return l line with vice grips?
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Old 02-23-2020, 02:43 AM
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greaseguy greaseguy is offline
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Default Replace or clean the purge valve

Likely you purge valve is stuck open. It Could be stuck open because of damage or wear or gummed up from poly Wvo. It is possible if you have the old brain it could be stuck open due to electronic issue. One way to test would be to unplug purge valve and see if system will bios pressure. I think you have solid state brain so unlikely an electrical issues.
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Old 02-23-2020, 04:16 AM
randy h randy h is offline
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Yes, I have the solid state brain. And the purge valve is new.
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Old 02-23-2020, 01:22 PM
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Wyn-Wyn Wyn-Wyn is offline
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Any changes when you unplugged the purge valve? My friend is having the same issue.
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Old 02-23-2020, 04:45 PM
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Default If Purged valve unplugged and system works

THe issue would likely be in solid state brain. If unplugged and system does not turn on then your new purge valve is not working. Sometimes new parts still donít work. I donít have a solid state brain so I am unfamiliar but likely new part is stuck open. I think you can take apart purge valve and clean it. Maybe even some light tapping and some solvent could loosen things. Be sure to remove o rings if you clean with solvents
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Old 02-24-2020, 06:27 PM
randy h randy h is offline
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Thank you, Wyn-Wyn and Greaseguy. I'll try those maneuvers and report back.
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Old 03-06-2020, 10:38 PM
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Chuckie Chuckie is offline
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The Purge vavle does get gummed up. Pull it and clean it till you can feel the plunger move freely and then test it by putting 12v to it before re-install.

Clay
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