how to test a dump valve?

lol4fun

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I have a problem, when I put a standard recirculating valve on my car it chatters like its not opening and I've tried this with 2 but when I put a forge one one it sounds like its leaking under boost. How can I test them?
 
The simplest way to test is to push the piston up by poking something through the bottom, then create a seal with your thumb over the top where the vac hose would go and see if the piston returns... If it does then it's ********
 
If the Forge one (assuming its a 007 or 008 and not the crappy split-r) has an o-ring on the bottom of the piston then it shouldn't leak at all under boost... if its a metal bottomed piston then get a service kit for around 15 quid that has the new design piston in or just buy a new OE valve

<tuffty/>
 
...and there are two threads in the FAQs about DV's and testing stuff etc... :)

<tuffty/>
 
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My two OEM ones are still both making a hooting noise :( Stuck the leaking 007 back on for now

This was me testing my 007

 
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My two OEM ones are still both making a hooting noise :( Stuck the leaking 007 back on for now

This was me testing my 007



Is that not leaking from the pipe? Difficult angle to tell!
 
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It was a while ago I recorded that but it was definitely leaking out of the bottom
 
Under how much pressure was that. And how long is that pressure on the dv? Is it constant while the turbos spinning? I know nothing about how this works im sure im going to look stupid here.
 
Pressure on the DV is there while 'on boost' dude... once throttle is closed then there is vacuum on the top that lifts the valve and release the pressure back into the TIP... if air is leaking past (as per the vid) thats air thats not getting to your engine and this equals power loss

<tuffty/>
 
Wow thats just incredible. I think im going to sell my 007 and get an oem. Sound wise?
 
Forge have revised the piston so should no longer leak... get a service kit for 15 ish quid which includes piston, o-rings and grease and treat it...

<tuffty/>
 
All 3 the piston drops as soon as I release it from pushing it up while blocking the vacuum end. I can blow through both the standard vacuum ends and hear it leaking. The forge one is a split r, I bought it before doing any research -.- lesson learnt
 
Which way around is the proper way?
Ordered a standard DV from my local vw dealers today, only £37 including vat.
 
All 3 the piston drops as soon as I release it from pushing it up while blocking the vacuum end. I can blow through both the standard vacuum ends and hear it leaking. The forge one is a split r, I bought it before doing any research -.- lesson learnt

Don't bother testing the split-r... they just leak... period! :)

<tuffty/>
 
as you had a split r im thinking that had the vacuum pipe horozontal, the stock dv's are vertical as tuffty taught me lol... so on the stock the vacuum pipe points at the sky.