Interesting Dump Valve Information For New Buyers And Owners. Servicing Etc

[S3 Paul]

Recently wen i cleaned my Forge DV and stripped and regreased it i noticed a very small stepped ring at the base of the piston... im guessing that will make it leak?
To test it in water for a leak i need to preasurise the side of the dv? and the small pipe on the top to the same level? My car sounds like an externaly gated rally car if i lift off from part throttle ... spring? faulty DV? needs shimming? bad map?

 

[A3 T]

this seems like a good place to ask. iv seen somewhere on the forum someone had fitted their DV backwards? im sure this cant be a good idea as surly it must put pressure back in to the turbo? but even so, nobody said that this was a bad idea and they knew they had done it? is there any reason/gain for doing this or is it a bad thing to do?

I remember a while back someone posted a good explanation on why you shouldn't run the DV like this but i cant remember the reason why .....lol

I think it was one of tufftys posts

 

[badger5]

Recently wen i cleaned my Forge DV and stripped and regreased it i noticed a very small stepped ring at the base of the piston... im guessing that will make it leak?
To test it in water for a leak i need to preasurise the side of the dv? and the small pipe on the top to the same level? My car sounds like an externaly gated rally car if i lift off from part throttle ... spring? faulty DV? needs shimming? bad map?

if chirping DV aint opening at all or not fast enough

 

[Dani_B19]

Bill im thinking of ditching my madmax dv and buying the newly rediisgned super sized forge valve, whats your thoughts on the forge one now forge have redone the piston and improved its sealing?

 

[badger5]

tufftys SS forge one sealed ok on bubble test
his does not have the o ring piston

 

[camscockle20vT]

This dump valve is verrrry filthy indeed, abit of spit and an old rag, elbow grease and some red lube did the trick nicely,

Note that the seals where shot and grease was... Shall we say ******* out!

Also the previous owner must of had the strength of a feild mouse, my 76 year old nan could of un done the dv with no problems, makes me laugh that people cant even refurb a 007p.

 

[JudderMan]

It's literally the easiest thing I've ever done. Did you get the new piston? Yours seems scored or is it just dirt?

 

[camscockle20vT]

Yeh its scored slightley i suppose, just minute abrasion really, iv not seen a used piston without it.

And no i just stuck with the old piston. I didnt have time to do the water and bucket test, but the finger and thumb jobbie sorted the men from the boys. Did this before and after to see how it preformed.

I only cleaned it because i had abit of a lumpy idle on occasion, usually going from on boost to stand still, thought it may of been sticking open, but it was just out right shot. Feels alot better now though, no lumpy idle as of yet.

 

[AudiS3-Turbo]

The only problem with the oem valve when used with b5 tip and jetex filter is the noise from it on light throttle, sounds like a trumpet, really annoying!

 

[badger5]

can you get a sound clip of this noise?

 

[AudiS3-Turbo]

When I'm back home later this weekend I can and will upload it.

 

[paultownsend]

Well. My 28 day old TPS supplied 710n valve has started honking like road runner on light throttle. Sounds ridiculous. I'm sure it's not holding boost either.

The thing is, I think my engine has too much vacuum at idle. -24HG.

Thats why I sold my forge 008. With a green spring it wouldn't shut at low revs, and with a yellow it would make the blower chatter at high rev dump. Shims made no difference.

Its only an AGU running a 185hp/220lbft map.

I assume a high vacuum means there are no boost leaks?
Does the PCV system have any effect on vacuum? As ATM I'm running a very crude system to atmosphere?

 

[Jason.s]

My standard 710n sounds like an owl with long hoots lol. Probably sounds like both the above posts its just hard to explain the sound. It must only have like 1500-2000miles on it. Did the n249 bypass at the weekend and now it does it all the time. Even longer and the slightest tiniest lift off the throttle and it does it. When cruising at any sort of speed 50/60/70/80 if you hold that speed steady it will do it as you`re foot is always moving the pedal from road bumps and dips. Have ordered another valve so going to try that tomorrow and see what happens.

 

[Jason.s]

http://img.photobucket.com/albums/v...E0C8F15-5190-000007A4796B3C02_zps5faa5cc5.mp4

not the best but it was quick on the way home and kind of demonstrates the noise. Can't really be bothered to go out with the go-pro to show it better lol. It's not doing it as much as it was this morning or yesterday but probably needed to be going faster as that video was at 50ish. Higher speed is much longer and heavier acceleration and pedal release it does it when changing gear too now since the n249 bypass.

 

[paultownsend]

Yes mine is similar, but more of a honk. Coming off lights throttle, lower revs. Grr!
Il whip the valve off tomorrow to see if its leaking.

 

[JudderMan]

Yeh its scored slightley i suppose, just minute abrasion really, iv not seen a used piston without it.

And no i just stuck with the old piston. I didnt have time to do the water and bucket test, but the finger and thumb jobbie sorted the men from the boys. Did this before and after to see how it preformed.

I only cleaned it because i had abit of a lumpy idle on occasion, usually going from on boost to stand still, thought it may of been sticking open, but it was just out right shot. Feels alot better now though, no lumpy idle as of yet.

Get onto Forge and get a new piston. I got mine for free as I bought the 007p in December and it started leaking a few weeks ago. Fit the new piston and it's spot on. No chirps.

Those that are honking like a goose I reckon you've bust the diaphragm. Get a new one. I'm sure Bill mentioned that they've changed suppliers and the new OEM ones aren't made by Bosch (not that it should make any difference) but they're cheap enough to replace.

 

[paultownsend]

The valve is from the new supplier and only 28 days old

 

[AudiS3-Turbo]

they dont leak,its just a noise they make when its on light boost on low vacume... annoying

Crap vid of the noise,difficult to hear with the phone but you should hear it.

 

[vrbob]

that noise is very annoying i dont think i could put up with that on a daily basis.

Well as my 007p is now running the new style piston and has been serviced so i thought i would try running with the green spring instead of the yellow for a bit. I also took the opportunity to replace the 4mm silicone pipe i used to do my n249 delete with some stronger 5mm braided hose as i was a tad concerned that the silicone was compressing under pressure as it does not have much strength really. The new hose is much tougher to squash between your fingers so i think it should do the job nicely.

 

[paultownsend]

HONK HONK! HONK HONK!

well i took off the new 710N valve today. i kept the silicone hose attached and had a quick suck. holds pressure perfectly. also tried blowing the side port and it wouldn't pass air for the life of me.

like the post above i don't trust silicone not to collapse under vacuum, so i used some thick walled 3mm ID clear PVC hose. piped back to my boost valve also as i had some hissing behind the dash. silicone is so easy to nip.
it's still honking like roadrunner.

i assume its just the diaphragm wobbling when going from vacuum to boost. annoying when your going up hill part throttle.

it still cant be normal. iv never known another 1.8t to do it.

 

[Jason.s]

That second video is pretty much what mine does yeah. Got a new valve today so i`ll try that when i get home. Doesnt sound like its going to cure it though

 

[<tuffty/>]

HONK HONK! HONK HONK!

well i took off the new 710N valve today. i kept the silicone hose attached and had a quick suck. holds pressure perfectly. also tried blowing the side port and it wouldn't pass air for the life of me.

like the post above i don't trust silicone not to collapse under vacuum, so i used some thick walled 3mm ID clear PVC hose. piped back to my boost valve also as i had some hissing behind the dash. silicone is so easy to nip.
it's still honking like roadrunner.

i assume its just the diaphragm wobbling when going from vacuum to boost. annoying when your going up hill part throttle.

it still cant be normal. iv never known another 1.8t to do it.

Silicon is better than PVC tube period as it will naturally spring back to its extruded (round) state once hot and if there is enough vacuum to close it up... PVC tube will collapse much sooner under heat and most PVC tubing installations I have seen have melted or fused flat once cooled down...

Small bore silicon vacuum tube would take more vacuum than the engine is capable of to collapse... for larger bore stuff (8mm and above realistically) use proper layered silicon hose...

<tuffty/>

 

[vrbob]

Have you got another DV you can try on the car to see if its any different?

 

[Jason.s]

Just fitted another new standard valve. Noticed the one I took off that I fitted back in October was one of the new branded valves so doesn't look promising that it'll sort it. Will see what it's like in the morning on the way to work.

I think its either going to be live with the hugely annoying noise which I don't think I can or buy a forge with new service kit

 

[vrbob]

look in the classifieds as for some reason there are quite a few second hand 007p`s for sale lol

get one as cheap as poss and then just get the service kit from forge with the new piston job done

 

[paultownsend]

that's me told good job i kept the old silicone!

as the current valve is only a month old, i may ask TPS for a replacement....

 

[S3quatt]

Crap you say.........

OE stays sealed at 2bar...
OE does not leak thru its ports under bubble test

And this makes it crap? Hmmm. You need to explain this to me.


What needs to be tuned? If it seals at up to 2bar what would you adjust??

If OE break they can be replaced for £30-£40

They're not bling nor fashonable but they work better than forum folklore and marketing would have you believe.....

Thorough testing reveals why the OE valve aint all that bad (when working)

Agreed on this!

OE one's cant leak unless the diaphragm is burst then it would be obvious there was a problem.

I have a forge one in a box at the back of the garage some place & went back to the OE valve, as it reacts as it should do.

My feeling is that for the forge valves to be 100% leak free, the 'O' rings would have to be thicker to create a proper seal, which in turn would be too stiff to react properly.

 

[S3quatt]

No thanks, on a standard or stage 1 car maybe but if my Forge broke today I would buy an OE in an instant

The ability to tune the springs to suit your setup is mainly the thing I appreciate, but mainly the fact that it is pimp. What you say is totally true, but the aftermarket ones are just a bit crap compared to an OE.

Corrected that for you

 

[Jason.s]

Well the drive to work was no different. Brand new valve same noise. So yeah as i mentioned further up its either live with it or get an aftermarket valve

 

[vanilla_ice]

look in the classifieds as for some reason there are quite a few second hand 007p`s for sale lol

get one as cheap as poss and then just get the service kit from forge with the new piston job done

Do this. I considered going back to OEM, but tried the new piston design. Now my car pulls noticeably (no logs) 'stronger' in the mid-to-high rev range.

I guess my original piston wasn't seated properly as it only had a thin band around where it closes against the main body of the valve.

 

[Eddie S3]

Thanks to this thread ive gone back to my OEM one!
007p is just over a year old I think


excuse the music (it was radio1..honest )

Edit: Just been for a drive and the oem one is now making that hooting noise people have posted about

 

[Jason.s]

Anyone got an old Bosch 710n laying about they could try? Incase its maybe the new kayser branded valves causing it? Unless anyone in this thread that's reporting the noise is using an older valve

 

[David_8]

Greetings from Briskoda.

Joined up just to post this, been reading this thread today, very interesting.

I got home and thought I should check mine.

I only cleaned it a few months ago so I guess the seals are shot.
Been having a few running issues lately so we'll see if this helps
I've dug out my OE Bosch job and fitted that back on after reading all this, I'll let you know how it feels in the morning.

 

[16Klappe]

Welcome to the site.

How did you find the OE valve?

 

[[Dave B]]

I test fitted a Kayser valve last week, it farted like a trooper so I refitted my 008p with a green spring.

 

[David_8]

Welcome to the site.

How did you find the OE valve?

Engine feels smoother through the revs, no so much of an on/off switch feel too it if that makes sense. And of course it's a little quieter which at my age is not a bad thing !!

Edit... It's the original valve which the car came with, about 10 years old, mind I've had the forge on for about 6 yrs

 

[badger5]

I test fitted a Kayser valve last week, it farted like a trooper so I refitted my 008p with a green spring.

it did what?

I'll fit mine to the lupo now to see...
fart sound, lol

mrsb will luv that!

not!

 

[Jason.s]

It makes the identical sound pretty much like when you blow over the top of a beer bottle and it makes that whistling sound.

 

[[Dave B]]

I found it most prominent at part throttle holding about 3k rpm, that's when she tended to let rip.

 

[Jason.s]

Sounds about right yeah.