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How long should a pressurized intake hold pressure? by Tweeder
Started on: 05-15-2014 01:03 AM
Replies: 4 (155 views)
Last post by: Tweeder on 05-15-2014 09:56 PM
Tweeder
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Report this Post05-15-2014 01:03 AM Click Here to See the Profile for TweederSend a Private Message to TweederEdit/Delete MessageReply w/QuoteDirect Link to This Post
I have found a few leaks by pressurizing the intake through an adapter on the throttle body. I have also,done the carb cleaner trick as well. I have really bad hearing so it's hard to pinpoint where a leak is coming from. I've had leaks from the maf, iac, upper intake under the supercharger, octopus on the top and an injector o ring. I just found a leak in the coolant loop thingy under the throttle body and sealed that up. Now if I pressurize the intake upto 20 psi it takes about 20-30 seconds for it to bleed down, no some or all might be coming from my contraption itself. The last 10 psi takes the longest to bleed. Does that sound acceptable?

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Report this Post05-15-2014 03:18 AM Click Here to See the Profile for sardonyx247Click Here to visit sardonyx247's HomePageClick Here to Email sardonyx247Send a Private Message to sardonyx247Edit/Delete MessageReply w/QuoteDirect Link to This Post
I'm surprised it lasts that long. normally it will/can bleed down real quick. I never tried it on a SC engine, the SC itself might be sealing it. as normally you will have a valve open, and leak down pass the rings or any valve overlap and it just all leaks out. When I pressure test for leaks I leave the compressor hooked up with a regulator for pressure.
I tried the "just add pressure and check" but real quick I found that doesn't work.


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Tweeder
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Report this Post05-15-2014 03:19 PM Click Here to See the Profile for TweederSend a Private Message to TweederEdit/Delete MessageReply w/QuoteDirect Link to This Post
I have a cap with a one way air valve like on your tire, and it's clamped to a silicone coupler and that's clamped to the throttlebody. Then I plug the lined at the octopus thingy, and the port off the throttlebody that goes to the,purge solenoid. I have no boost bypass or egr so no leaks from there. I have a vacuum guage at one port at the octopus, and I add air through the throttlebody and watch the guage and spray soapy water all over and look of bubbles. I have done this numerous times on this motor as well as others. Sometimes I can't access certain parts of the engine as with carb cleaner it has to be upright, so a spray bottle gets the solution there.

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Report this Post05-15-2014 09:53 PM Click Here to See the Profile for SpoonSend a Private Message to SpoonEdit/Delete MessageReply w/QuoteDirect Link to This Post
I'm in sardonyx24 corner. Ring gap, valve overlap, etc. your going to loose pressure real quick. You may have a better shot by forcing a potato into each tail pipe then pressurize the whole system head to toe.

Spoon

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Tweeder
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Report this Post05-15-2014 09:56 PM Click Here to See the Profile for TweederSend a Private Message to TweederEdit/Delete MessageReply w/QuoteDirect Link to This Post
Well what ever I'm doing seems to be working as I have found a few leaks this way. I see now with all other factors it will not get a perfect seal, but I'm happy for now with a 20-30 second bleed down from 20 psi.
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