HOW TO - Boost Leak test without a smoke tester (off car)

This section shows how to carry out modifications to your 1 Series. Please remember that if you are modifying your car to take photo's at each step and document the mod in here.
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slindborg
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HOW TO - Boost Leak test without a smoke tester (off car)

Post by slindborg » Mon Apr 16, 2018 8:11 am

Its going to be relatively picture light as the work to get here is involved.

First off I take no responsibility for damage to you or your car etc blah blah.

Parts from your CAR that are needed:
Turbo
Turbo-Intecooler hose
Intercooler
Intercooler to EGR hose (with temp sensor still fitted)
EGR valve.

Stuff that you need:
Paddling pool, 3ft is ideal and only £6 in Argos.
A flexi pipe that is 45mm internal, I used a plumbing pipe from screwfix for about £9 including the clips.
Clips to suit above
A blanking bung that fits the above pipe and a valve or air fitting of some sort. I cheated and used some of the coolant system pressure test kit I had.
A pump, high volume ideally otherwise you will be there for days, I used a Bell Air attack track pump that I use to inflate tubeless tyres on my MTB.
Something to blank off the manifold end of the EGR valve. More on this below.
Some silicone sealer for the above
4x M6 Bolts+nuts (not nylocs)+washers ideally.
Soapy water and a brush
Cinder block and water

Regarding the Blank for the EGR valve, I used a piece of MDF as it was easy to cut/drill and I had it to hand. What happens is it seals well with silicone, but once the face sees 20PSI it starts to leak internally, which was very pretty with some soap on the side as it looked like a foam machine belching out streams of bubbles :lol: I covered it with plastic and it sealed properly then.

Assemble as shown below:
Image

I took it all upto around 35PSI, which took approx 20-25 pumps on the high capacity track pump... Cardio gainzzzz :lol:
IF yours isnt leaking in the bits underwater, then use the bubbly solution on all joints/pipes that are suspect.
IF the pressure does not drop very much, then its unlikely that the leak is here.

Here is my leak on the boost-cooler joint
Image

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marco_polo
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Re: HOW TO - Boost Leak test without a smoke tester (off car)

Post by marco_polo » Mon Apr 16, 2018 8:23 am

Nice work, I find tyre punctures & leaky wheel valves/beads in a near identical paddling pool. :)
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slindborg
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Posts: 133
Joined: Mon Apr 28, 2014 9:30 am
Location: Bishops Stortford, Herts

Re: HOW TO - Boost Leak test without a smoke tester (off car)

Post by slindborg » Mon Apr 16, 2018 9:03 am

Its not a pretty solution, but it found the problem given I couldnt drive the car, and for about £20 :)

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