Let’s get to this Seafoam HowTo
Using Seafoam on P2 Volvos like S60, V70, XC70
If you’ve looked at my How to Use Seafoam tutorial, you’ve probably noticed that the subject car is my 1997 850 that has a convenient vacuum tree, useful for sucking the Seafoam into the intake (or easily adding a boost gauge). But 2001+ Volvos don’t have this, so what do you do? Velorider shows us how to use the brake boost vacuum line to pull Seafoam into your S60, V70, C70 or XC70’s intake.
This post is simply an extension to Matthew’s great How To Seafoam your Volvo. The following describes only the steps required for the intake stage using the brake booster vacuum line on the 2.4 S60. I was unable to find the vacuum tree mentioned in Matthew’s post, either this cars don’t have one or it looks significantly different. The following is a pictorial for Seafoam’ing the intake on a 2.4 S60. Read Matthew’s post first for full directions and heed any warnings.
Before starting you’ll need a 3/8 inch inner diameter (3/8 ID) hose and a funnel with a small spout like a transmission funnel. Connect the hose to the end of the funnel.
Most common location to Seafoam is via the brake booster line, on the S60 its PITA to get to. The brake booster is the big black round thing connected to the firewall inside the engine compartment in front of the driver. Follow the brake booster vacuum line around under the intake box to where it enters the manifolds. Notice the green clip in the picture, this is the opposite end of the brake booster vacuum line, just before it enters the manifold.
Next using pliers slide back the green clip and disconnect the line. I found using a screw driver to help loosing the line makes the job much easier. Try disconnecting the line slowly to allow time for the vacuum to decrease. There will be a hissing noise when you discount the line. Now connect the hose and funnel where you discounted the brake booster vacuum line.
Almost done. Now have you wife or even better a buddy start the car. The car will tend to stall with the line discounted so you need to keep the rpm’s around 2K. You should hear a loud hissing noise from the funnel. Now SLOWLY AND CAREFULLY pour 1/3 to 1/2 of the Seafoam into the funnel. Don’t let the Seafoam pool in the hose, the vacuum should prevent this. But to avoid this issues all together don’t create any low spot in the funnel hose.
After pouring SLOWLY AND CAREFULLY 1/3 to 1/2 the Seafoam turn the car off and let it sit for 5 to 15 minutes. Now without the neighbors seeing start the car and drive it around until it stops burning white smoke.
Again read Matthew’s original post first! Good luck and don’t destroy your engine.
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