What is the actual purpose of the PCV valve? Why not just run a constant vacuum to the valve cover? What does the valve actually control? I'm just thinking that an easy way to "take care" of the blow by problem is to create more suction to get rid of the oil overflow instead of having it dump out of the valve cover.
Any opinions?


'88 Sahara, 4.2 that runs. The rest is getting there![img]/wwwthreads_images/icons/blush.gif[/img]

BTT


'88 Sahara, 4.2 that runs. The rest is getting there![img]/wwwthreads_images/icons/blush.gif[/img]

[img]/wwwthreads_images/icons/smile.gif[/img] If you did not have a valve which throttled at higher vacuum settings, you would be so lean at idle that the engine would quit. Why not take a page out of the zero-vacuum diesel engine book and make an oil recovering type of setup? A tall vertical pipe with another pipe dropped down inside about halfway. The inside pipe connects to the engine valve cover, and the top end of the outside pipe connects to the air cleaner. Then the bottom of the pipe has a connection back to the pan or block for the oil to return.[img]/wwwthreads_images/icons/crazy.gif[/img]

CJDave
A Jeep Skunkworks run by Moonguys[img]/wwwthreads_images/icons/wink.gif[/img][img]/wwwthreads_images/icons/tongue.gif[/img][img]/wwwthreads_images/icons/laugh.gif[/img], buildin' the ultimate SNOJEEP!

You need a new motor if the blowby is excessive . If the motor is using a lot of oil and getting into the air cleaner than it is motor time . There are no gimicks to cure blowby . If there were Jeep would have installed one on the assembly line . There is always someone with a BS trick for a Jeep to cure everything .

[img]/wwwthreads_images/icons/frown.gif[/img] BS "tricks" as you call them is what separates REAL mechanics who can get-the-rig-home-no-matter-what from the have-it-towed-to-the-dealership weenies. You could not even COUNT the number of 'trick' modifications that this BBS has produced, not the least of which is the TR upgrade. Everyone who has been around a Jeep for any length of time knows that the 258 engine has a premature blow-by problem, and the longer you can go before you have to overhaul it prematurely the better off you are.[img]/wwwthreads_images/icons/frown.gif[/img]

CJDave
A Jeep Skunkworks run by Moonguys[img]/wwwthreads_images/icons/wink.gif[/img][img]/wwwthreads_images/icons/tongue.gif[/img][img]/wwwthreads_images/icons/laugh.gif[/img], buildin' the ultimate SNOJEEP!

If there's that much blowby, the engine needs to be rebuilt - no way around it. If the oil recovery thing-a-ma-jig was needed, Jeep probably would have put one on there.

About running a constant vacuum to the valve cover: It would create a lean condition, causing the engine to run very poorly, having the same effect as a massive vacuum leak. The PCV valve throttles the flow to limit the amount of vacuum that "leaks"

-Derek Schwab
'97 Sidekick Sport
'83 CJ-7

[img]/wwwthreads_images/icons/tongue.gif[/img] Well Stooby, there you have it. It looks like you are totally and completely screwed. It would appear that the best thing for you to do is just have that Jeep towed to the nearest Jeep dealer and have them install a brand new engine. After all, if there was a way to control blow-by, the Jeep factory would have included it with the Jeep in the first place. You have two "expert" opinions on that.[img]/wwwthreads_images/icons/laugh.gif[/img] And I must further advise you against adding any sort of non-stock modification to your Jeep. After all, if your Jeep needed it, it would have come that way from the factoreeee. Sometimes this BBS makes me just shake my head.[img]/wwwthreads_images/icons/laugh.gif[/img][img]/wwwthreads_images/icons/crazy.gif[/img]

CJDave
A Jeep Skunkworks run by Moonguys[img]/wwwthreads_images/icons/wink.gif[/img][img]/wwwthreads_images/icons/tongue.gif[/img][img]/wwwthreads_images/icons/laugh.gif[/img], buildin' the ultimate SNOJEEP!

damn.. you mean to tell me that little trick i did and ran for like a year.. I WASNT supposed to do.. well.. thanks for telling me now..
i hear you dave.. all this time and money i have wasted doing stuff to my and others jeeps.. i really didnt need to do.. since jeep didnt put it there.. it wasnt needed?
i dont think any jeep engineer ever ran tellico or blew out a rear main seal in st. louis while trying to make it to north carolina.. pansies.. i laugh at them[img]/wwwthreads_images/icons/laugh.gif[/img]

http://www.jeepgod.net


<font color=orange>survival is instinct, but living takes guts</font color=orange>

We put a mason jar "inline" on one of my friends jeeps in college to stop the blow by. It kept the filter clean, he just had to empty it every now and then. Engine ran fine too.




Jason

----------------
[]llll[] '90 YJ & '88 Grand Waggie

Do you "get a new motor" guys work for Jeep or something? I dont get your logic? or complete lack of... If something is broken, fix it, dont buy the same thing that will break again when you use it the same amount... The definition of stupidity is doing the same thing and expecting different results... or so Im told