Possible Intake Leak

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Nov 22, 2006 | 08:06 PM

sgrol

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Laughing Gas

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From: Gig Em, Tx

Possible Intake Leak

I suspect I may have a leak between my turbo and heads. (high EGt and low boost) I have rigged up a way to pressurize from before the turbo to about 20 or 30 psi. Question: will I get a leak through the intake valves preventing me from pressuring up and detecting a leak. Is there a magic point in the crank rotation where all valves are shut? Any help in doing this would be appreciated.

Nov 22, 2006 | 08:10 PM

sgrol

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Laughing Gas

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From: Gig Em, Tx

BTW: just removed, cleaned and visually inspected 4 boots on both sides of intercooler. Did not 'see' any problems.

Nov 22, 2006 | 08:12 PM

PowerstrokeJunkie

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From: 21791

I do not believe there is a point that you could pick out which would permit all of the intake valves to be closed. However unless a cylinder is in valve overlap, it should not matter because the exhaust valves would be closed if the intake valves were open, and i do believe that the rings will seal 30psi when cold. Be sure to keep that pressure in there for ONLY as long as you need it, because there is no oil pressure holding the seal tight in it's groove. You are pressurizing the turbo with no oil pressure and that *may* have adverse affects, say if you leave it pumped for an hour or so, to check for leaks. If you have eliminated the boots, try making a cap for the compressor manifold inlet (from cold side CAC tube), so you can pressuize everything but the intercooler. It may be an intake plenum. lots of soapy water.

Nov 22, 2006 | 08:12 PM

cookie88

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From: Cabot, Arkansas

The valves position won't matter. If you have a top side leak you'll find it very quickly once you apply the load.

Nov 24, 2006 | 06:07 PM

sgrol

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Laughing Gas

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From: Gig Em, Tx

Thanks for the replies. Pressured it up today and found several small leaks. Nothing blown just loose clamps. Hope to see some improvement.

Dec 14, 2006 | 11:05 AM

bc56845

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From: Candler, NC

What did you rig up to pressurize the system, a big chunk of rubber or something to fit in the turbo ?

Dec 14, 2006 | 11:11 AM

sgrol

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Laughing Gas

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From: Gig Em, Tx

I used a 4" PVC cap that fits inside of the rubber sleeve that connects to the piece with the valve cover vent. I drilled a hole in the cap and installed an air fitting to hook up to my air compressor and then used the regulator on the a/c to let 20 psi into the system.