Brake Booster Check Valve Hose Question

warmblood58 · Post by **warmblood58** » 22 Sep 2017, 18:19

Hello All! From brake booster/check valve on the turbo cars, where does the other end of the booster vac hose terminate/ connect to and also, why is such a cheap little plastic check valve/grommet so damn expensive at 50.00 plus dollars??? Thanks!

Post by **wizechatmgr** » 22 Sep 2017, 18:38

Assuming yours is like mine - it works through venturi effect of pressure passing past it at a designated rate, creating a vacuum, similar to the cheap fertilizer injectors that were long ago used at residential properties.

Mine is black and about 2-3 inches long. It has one connection to intake manifold and two out - one of which to brake booster.

Why on the price? It is Volvo. That part may only need to be replaced every 15-20 years - if ever. When you figure the cost per mile it is likely costing you less than what you are likely to pay for a single bar of soap on a yearly basis.

Post by **erikv11** » 22 Sep 2017, 19:53

warmblood58 the junkyard is your friend on this one, I have not seen those go bad and wouldn't hesitate to get a used one and save about $48.

Post by **scot850** » 22 Sep 2017, 20:20

They do go bad but not a common issue. /but like the guys say, the one that went out on me was 16 years and 165,000 miles on it.

Junkyard is your friend. Usually went I pull them at PnP I have pulled other parts and they don't charge me for them.

Neil.

Post by **scot850** » 22 Sep 2017, 20:20

They do go bad but not a common issue. /but like the guys say, the one that went out on me was 16 years and 165,000 miles on it.

Junkyard is your friend. Usually went I pull them at PnP I have pulled other parts and they don't charge me for them.

Neil.

Post by **kahl** » 22 Sep 2017, 21:06

Thank you for the description wizechatmgr. What are the symptoms when this check valve fails? All three of my turbo P80 s have this valve but I have never given this valve any thought.

Post by **wizechatmgr** » 22 Sep 2017, 23:17

Likely an increase in the amount of pressure having to be applied to the brake pedal.

Post by **erikv11** » 23 Sep 2017, 07:23

If the check valve isn't working, the problem will be air gets into the master cylinder. So the usual symptoms there: hard pedal (excess pressure in the master cylinder), or soft and spongy pedal with reduced braking in response to pedal travel (air gets into the brake lines).

warmblood58 · Post by **warmblood58** » 23 Sep 2017, 09:46

Thanks all, yea, I was thinking about picnpull as I drifted off to sleep

warmblood58 · Post by **warmblood58** » 23 Sep 2017, 09:48

Thanks all, yea, I was thinking about picnpull as I drifted off to sleep. When I go, I usually pull other parts along with certain bolts, clamps, nuts and other hardware -