19bonestock88's 04 Redline BUILD:finishing somebody else's project...
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Joined: Mar 2014
Posts: 1,363
From: Louisiana
Meaning full motor?
I have rods and pistons for an lsj. Just not the other stuff. I am really leaning towards the PCV line to crank case like in this thread: Dip stick popped - Saturn ION RedLine Forums
Or might just need a breather to prevent the back pressure.
Do a compression check yet?
I have rods and pistons for an lsj. Just not the other stuff. I am really leaning towards the PCV line to crank case like in this thread: Dip stick popped - Saturn ION RedLine Forums
Or might just need a breather to prevent the back pressure.
Do a compression check yet?
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Joined: Feb 2013
Posts: 1,496
From: Wellington, NZ
Yeah, I meant an L61 long block...
I haven't checked compression yet, as I believe a cold or slightly warm compression test will reveal nothing... I need to run it hard, until it loses boost, and then check... This will reveal if the pistons are the cause of my boost loss, and the cause of the dipstick coming out... I thought about sticking a bigger/thicker o-ring on the SOB and calling it good for now...
I haven't checked compression yet, as I believe a cold or slightly warm compression test will reveal nothing... I need to run it hard, until it loses boost, and then check... This will reveal if the pistons are the cause of my boost loss, and the cause of the dipstick coming out... I thought about sticking a bigger/thicker o-ring on the SOB and calling it good for now...
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Joined: Feb 2013
Posts: 1,496
From: Wellington, NZ
I need to locate a compression tester before I can do a test... I blew out some oil today, running the car at full power/boost...
I've begun testing how much it will take before popping the stick... Tests usually have lasted three seconds or so... 10psi? Fine. 13psi? Fine... But, when I went WOT through 2nd and 3rd gear, I blew out my stick...Somehow, either the extended pulls or boost above 13psi results in a blown out stick...
There is, however, a moderate vacuum at the PCV hose(the one that goes on the intake) at idle... Is this supposed to be?
I've begun testing how much it will take before popping the stick... Tests usually have lasted three seconds or so... 10psi? Fine. 13psi? Fine... But, when I went WOT through 2nd and 3rd gear, I blew out my stick...Somehow, either the extended pulls or boost above 13psi results in a blown out stick...
There is, however, a moderate vacuum at the PCV hose(the one that goes on the intake) at idle... Is this supposed to be?
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From: Slightly off center
Yes, there may indeed be vacuum at the outlet of the PCV valve AT IDLE as the engine is operating at maximum vacuum under these conditions --- just like the answer to the why am I reading negative boost values at idle.
The PCV valve CAN and DOES allow airflow in both directions. It is designed for equalizing SMALL differences in pressure. It WILL in time build pressure up to the boost value.
At Idle:
There is vacuum at the throttle body where the PCV outlet hose attaches.
There is vacuum at the end of the PCV outlet hose itself.
The intake manifold vacuum is stronger so the crankcase is being vented to the intake.
At WOT
The engine vacuum is at its lowest. Again, venting through the PCV is minimal -- it is for small pressure equalization, not for high pressure equalization that would require much larger volume of flow.
I guess the work around is a breather and catch can to avoid the flow restriction and to equalize the pressure.
Do the compression test.
My bro in law helped immensely w this post
The PCV valve CAN and DOES allow airflow in both directions. It is designed for equalizing SMALL differences in pressure. It WILL in time build pressure up to the boost value.
At Idle:
There is vacuum at the throttle body where the PCV outlet hose attaches.
There is vacuum at the end of the PCV outlet hose itself.
The intake manifold vacuum is stronger so the crankcase is being vented to the intake.
At WOT
The engine vacuum is at its lowest. Again, venting through the PCV is minimal -- it is for small pressure equalization, not for high pressure equalization that would require much larger volume of flow.
I guess the work around is a breather and catch can to avoid the flow restriction and to equalize the pressure.
Do the compression test.
My bro in law helped immensely w this post
Last edited by derf; May 25, 2015 at 10:28 PM.
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Joined: Feb 2013
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From: Wellington, NZ
I have a compression tester borrowed, now to find some time when I'm not too exhausted to remember how, to test the car... I figure the base compression test, warm and dry, plus a 30sec leak down test should point a finger at any internal issue...
I have developed a work around in the meantime... I have fabricated a "hold down spring" for the dipstick, and I plan on installing a snap ring on the dipstick tube, and anchoring the dipstick with above mentioned spring... Permanent fix? Nope, but it'll do for now... Now to find a suitable snap ring, and borrow some snap ring pliers...
Not to mention that nothing happens if I mind my boost/RPM level and try and keep below 14psi/5000 RPM... I haven't popped the stick in a couple days...
I have developed a work around in the meantime... I have fabricated a "hold down spring" for the dipstick, and I plan on installing a snap ring on the dipstick tube, and anchoring the dipstick with above mentioned spring... Permanent fix? Nope, but it'll do for now... Now to find a suitable snap ring, and borrow some snap ring pliers...
Not to mention that nothing happens if I mind my boost/RPM level and try and keep below 14psi/5000 RPM... I haven't popped the stick in a couple days...
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From: Slightly off center
