Club G40 Forum

Technical => Turbochargers => Topic started by: cheys03 on September 12, 2010, 06:02:06 pm

Title: Bosch recirc valve
Post by: cheys03 on September 12, 2010, 06:02:06 pm: I've bought a used VW/Audi recirv valve, part number 034 145 710 C which I believe is reasonably commonly used with G40 turbo conversions. It's the same as in the photo below pinched from an American Audi site.

(http://www.s4biturbo.com/files/bosch_side.jpg)

The valve doesn't appear to operate as I would expect, but would like to make sure I'm not misunderstanding the valve before condemning it...

If I suck on the vacuum line then it will suck air through the 'pressurized air dump in'. When connecting the valve to a vacuum line on my engine it won't open, but when the valve is gently pushed open through 'pressurized air dump out' the vacuum will hold the valve open.

I suspect the diaphram between the vacuum side and the boost side of the valve is shot, but looking for confirmation please chaps. Cheers.
Title: Re: Bosch recirc valve
Post by: cheys03 on September 15, 2010, 10:28:43 pm: Yup, fooked seal

(http://i734.photobucket.com/albums/ww343/cheys03/IMG_3910.jpg)

(http://i734.photobucket.com/albums/ww343/cheys03/IMG_3909.jpg)

Looks like it's torn (no I've not sawn into it!) where it is folded and sealed under the cap. Damn nuisance.
Title: Re: Bosch recirc valve
Post by: Robin on September 15, 2010, 10:52:03 pm: these dump valves are crap, they don't last long as the rubber easily splits, i have about 5 of them in the boot of the car as spares, they don't last long with 22psi of boosts!
Title: Re: Bosch recirc valve
Post by: cheys03 on September 15, 2010, 10:56:45 pm: Duly noted! :D
Title: Re: Bosch recirc valve
Post by: hayesey on September 16, 2010, 09:12:05 am: yeah I had one pop on me half way through a track day. Ran the rest of the day with a screwdriver handle shoved into the dump valve hole :D
Title: Re: Bosch recirc valve
Post by: vwmk3jon on February 13, 2011, 07:26:38 pm: Wont buy one of those then! Lol
Title: Re: Bosch recirc valve
Post by: Doc J on February 14, 2011, 12:32:23 am: My opinion - GReddy Type S insted of the Bosch one - good recirc dump valve, hard to appear damage on it ;)

(http://www.autopassion.co.nz/site/images/Greddy%20TypeS%20BOV.jpg)

Negatives - may be too big valve diameter (35mm insted of the 24mm in Bosch one) and the price of it!
Title: Re: Bosch recirc valve
Post by: hayesey on February 14, 2011, 09:47:24 am: Tial make some nice ones too. Although I'm currently using a right chavvy one that a mate found in his shed, I think it was used on an escort rs turbo, it's anodised bright blue and makes a right racket but it's not blown up yet. I might save some pennies for a nice Tial one though!