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Tried to do a leak test today....

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Old Jun 13, 2009 | 04:48 AM
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Default Tried to do a leak test today....

I have tried to do a leak test today. I have used electric pump (it says up to 250 psi on it - also tried to put same air into tyre and it works well) however It didn't work - gauge didn't move, stayed at zero all the time, there was pressure in hoses after a while but when I stopped compressor air released in 10 sec from hoses and I could not hear any leak only bubbling (can be oil).

I removed oil cap and clamped oil breather pipe.

any idea?
 
Old Jun 14, 2009 | 07:42 AM
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i assume its one of those emergency 12v tire pumps. that wont work, it doesn't flow a high enough volume of air.

Also, removing the oil cap introduces a 2" round hole into the system you're trying to pressurize. There will always be some leakage around the valves and whatnot, clamp the line out of the valve cover (just before the hockey puck looking thing), and leave the oil cap on, and try again.
 
Old Jun 15, 2009 | 07:08 AM
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"clamp the line out of the valve cover (just before the hockey puck looking thing), and leave the oil cap on, and try again. "

have you got any pics of what I need to clamp?

Actually I have clamped that hose on the photo where is red arrow.

Anyway pressure from electric pump was very low however I have found a leak in vacuum hose - under manifold - challedge to change it now..
 
Attached Thumbnails Tried to do a leak test today....-pcvvacuum-via.jpg  
Old Jun 16, 2009 | 06:43 AM
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thats the hose i was talking about.

changing lines under the manifold isn't too bad once you get that steel bracket off. careful with your dipstick tube (clips to metal bracket), they get brittle over time and break when you do things like, touch them.
 
Old Jun 28, 2009 | 02:42 PM
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The latest update...I have fixed broken vacuum hose (red arrow on photo)
and also found another broken hose (photo 2)however I is still as same as it was. Have done another logs and pressure is still very very low.
Any idea somebody?
 
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Old Jun 30, 2009 | 06:17 AM
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Originally Posted by sabikeuk
The latest update...I have fixed broken vacuum hose (red arrow on photo)
and also found another broken hose (photo 2)however I is still as same as it was. Have done another logs and pressure is still very very low.
Any idea somebody?
any body idea?
 
Old Jun 30, 2009 | 06:34 AM
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keep looking. if pressure is still really low when you try to test, its gotta be a decent size leak, either a torn hose, or something came disconnected.
 
Old Jul 2, 2009 | 06:58 AM
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I have done another leak test today but I only was able to pump 15psi, the hoses were full of air but I couldn’t hear any air coming. Anyway turbo is peaking only 15psi – it is same value at I was able to pump - could it be a connection between these two?
 
Old Jul 2, 2009 | 04:08 PM
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I have done some test today, I have unplugged hose which goes from N75 to actuator and connected pump to it, set 1psi on pump and started pump. In half sec pump stopped and actuator rod moved immediately. However when I looked to pump there was 27 psi :? .....when I unplugged pump rod moved back.

Does it mean that actuator hold 27psi and it works properly?


Anyway I have decided to test again my DV. I pushed the piston of the valve upwards against the spring (it moved without restriction). Then with the piston pushed fully up, with the spring compressed, I placed my finger over the top nipple to form a
seal. see photo 1

Then I released the piston, keeping my finger in place but piston moved about 5 mm down - see photo 2

After I removed my finger from the nipple, at which point the piston travelled another 2 mm back and made noise (shoot).

Here is re-assembled DV - I don't know what type is it - it was on the car when I bought it.

I have tested it maybe 10 times with same result. Dost it working properly or is it faulty?
 
Old Jul 3, 2009 | 10:05 AM
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Looks like a Forge 007. Good DV, just keep it well greased with synthetic grease, and clean it a couple times a year.

From everything you've described, the DV is fine. Just keep it well greased like I said.

I still think you need to thoroughly go over all hoses with some soapy water. You haven't mentioned if you've done that. Theres a lot there, more than just the intake and vac lines relating to the turbo. Theres more crankcase venting and emissions stuff than turbo stuff, and its all pressurized when you leak test.


This is 80% of the crankcase ventilation system. Mine was full of leaks, so i removed it and installed a couple of stainless braided lines running to a catch can. It doesn't recirculate oil vapor like the stock system did, which means if the car is warm and at a standstill, I smell hot oil inside the car, but at least I don't have that mess to deal with leaking anymore.
 

Last edited by achTTung; Jul 3, 2009 at 10:08 AM.



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