Vacuum line clamps

855 moneypit · Post by **855 moneypit** » 16 May 2010, 13:04

How critical are these clamps ( #s 21 & 22 ) for the lines coming off of the BCV? There weren't in place when I bought the car 4 years ago.

I have seen some with the original clamps and others have been zip-tied.

Post by **JDS60R** » 16 May 2010, 13:07

Both are very important as they keep the lines on during the pressurization of the turbo and if blown off can cause overboost and engine failure.

They are a constant tension style clamp and need to remain that type to best suit the changing thermal conditions that surround a turbo. If a small band clamp had to be used ( and I do not suggest it) then clamp it on - wait 1/2 hour for cold flow (movement of rubber line under clamp) to finish and retighten.

Best bet is to get high quality new ones and not worry.

Keep Boosting,
John

Post by **charlyW** » 16 May 2010, 14:55

i don't have any clips on my vacuum hoses but they are silicone.

Can anyone tell me why my TCV is piped up differently to the picture

855 moneypit · Post by **855 moneypit** » 16 May 2010, 20:44

charlyW wrote:i don't have any clips on my vacuum hoses but they are silicone.

Can anyone tell me why my TCV is piped up differently to the picture

From what I was told the TCV design was changed. The one above is an early design.

Post by **j_cd** » 17 May 2010, 09:59

The Volvo dealer said those constant tension clamps require a special tool, but they didn't say what it was. I tore one up on my coolant expansion tank hose. They gave me two sets of clamps with the new hose. I'm using the screw clamps for now, because the dealer said you only get one shot at the constant tension ones.

Post by **jblackburn** » 17 May 2010, 10:05

The green clamps? Special tool? Bah. Your fingers or a set of needlenose pliers. Just stretch it open slightly bigger than the rest of the hose, slide it over, and let go. It's easy, I got a bunch of them from IPD with the new TCV I ordered, but I'm sure a dealer or if you need to order other parts online, just throw in a bunch with your order.

whoa · Post by **whoa** » 17 May 2010, 10:09

To be filed under "tools it would be cool to have":

Post by **charlyW** » 17 May 2010, 12:50

I've got a set of those they're great for undoing Volvo clips but as JA says just a set of needle nose pliers does the same job or if you fish for carp the hook removing tonges do a brilliant job too and you can lock them

flip222 · Post by **flip222** » 23 May 2010, 11:59

I have a question? Do lines 20 and 18 in that diagram go to engine vacuum? I'm reinstalling a turbo in an 850 that some shop butchered. Thanks in advance.
Kent.

Post by **j_cd** » 23 May 2010, 15:39

BTW I wasn't talking about the green clamps. Now that I've replaced a few vacuum lines I know what you mean by the green clamps, but the ones on the coolant line are not the green ones. They're the weird ones, I don't know what they're called, but supposedly they're single use. Once you put one on that's it. Not reuseable.