chevy1500z71

i think its time, my truck ahs been leeking oil, i inspected it all and mainly it was spewing from an oil pan bolt, fixed that. but what i also notice is the rear main seal(which is brand new) cant really take the heat from all the crancase pressure, it leaves a residue of oil all over the transmission inspection cover. i got to thinking, and i really dont think anything is wrong with my motor, i think i need an evacuation system, all i have is breathers on the valve covers and i can watch them puke smoke when i rev the motor.

so how do you set one up for cheap? im looking for information how to set one up. i see the lt-1 smog pump is popular because its electric. but what about a pulley driven unit from a disel motor like say of of a old cummins or ford powerjoke, i know they use vacuum pumps to power the vacuum brakes and such, but will they take the heat from oil and much higher rpms then they are intended to spin?

the next question is how does it go, do i run a pcv or right off of the valve cover into the vacuum pump? do i need to run a water separator/filter before the pump. and id route the exhaust from the pump under the truck, i wouldnt put it back in my intake, i really wouldn't care if it puffed a little smoke under the truck.

Orr89RocZ

iTrader: (20)

Just 1 breather per cover? may drill and put in another breather per side to see what happens. I have to redo mine as i got backpressure issues with my turbo. I run two 5/8" rubber lines into a vented oil catch can. I see it leaking out the cover fitting so i know its getting vented there, just not sealing well enough.

You can try to run an electric vacuum pump, plumb both covers into a T and run that line to the vacuum pump. DO put a seperator inline with that pump so it doesnt suck up oil.

To do a PCV valve, I think you can plumb the PCV line to the intake tubing since its usually under a vacuum. Just need a oil seperator/catch can inline so you dont absorb oil into the motor. If you have vacuum lines on the intake manifold for the blower, you will need a check valve to prevent boost getting into the crank case. I think its better to run it to the intake air inlet tube but not sure how much of a vacuum there is there.

chevy1500z71

iv got big breathers on the covers, adding more breathers is kind of a badn aid, but it would work i supose. id really like to get an evacuation system going tho.

im talking about runing a pcv valve on the valve cover, no check valves, no catch cans, none of that because whatever the evac pump pulls out im going to have it just blow out of a line routed under the truck, not back into the motor.

basically what iv got in mind is this(tell me if im leaving anything out here), these pcv valves http://www.summitracing.com/parts/MOR-68780/ but im not using the exhaust evac. ill run that to a separator(like one for a compressed air system wold work i gues, or maybe a marine fuel water seperator?) then to the smog pump, and then the exhaust side of the smog pump will just have a line routed under the truck to blow the bad stuff out into the air.

what im really interested in tho is the choice of vacuum pump. would a pulley driven unit work better because it would pull more vacuum as rpms increase?

Jay_rich

iTrader: (4)

get the moroso exhaust evactionuation deal, route a hose to a check valve that goes to the exhaust so the exhaust pressure pulls it out. Oil hotrod trick.

Im gonna do it too

Jay

chevy1500z71

that doesn't work with mufflers (lets not argue this, it works for some people, others not)and i dont want to introduce yet another problem for messing with my widebands readings/ possibly fouling it.

so do i need to run the pcvs on the cover or not? they seem like they would do nothing but restrice the vacuum pump. to be honest they are ugly, id rather put a big AN fitting on the cover and run the line like that.

chevy1500z71

no idea on weather i need to run pcvs or not?

tom86iroc

iTrader: (1)

try runnin the PCV first friend had the same problem till he added his PCV again no smoking at all

Orr89RocZ

iTrader: (20)

If you run a vacuum pump, no dont need PCV valve. I dont see the point in it. Just need a catch can/oil seperator in line so the pump doesnt suck up oil.

???

iTrader: (5)

sounds like you want a really good one, so I'd say just spend the money and get the belt driven one, now trying to use a smog pump of some kind. the good ones will pull bbc drag motors down into a vac at wot, or so I've been told. I've also heard it picks up hp by letting your rings seal better. only bad park is smelling all this blowby on a street car. every time you get out you will smell like it. for that idea either run it into the exhause after the widebands or dump it back into the intake to be reburned after you catch the oil. prob hurt hp that way, but depends on how you use your truck I guess.

Orr89RocZ

iTrader: (20)

Wonder if you can run it through the charcoal canister to deaden the smell? works for the gas tank

chevy1500z71

theres an idea.

but isnt this pump going to be pooring out all kinds of oil smoke? i was going to just run a line pretty far back, dump the exhaust from the pump about where ill dump the exhaust at. the truck smells like unburnt fuel anyway, im not running cats and i get 7 mpg to give you an idea of how much fuel goes through this thing lol. lets face it, my truck isnt practical, who cares, my main concern with this truck is maximum performance and reliability, some oil smell wouldnt bother me.

i dont understand the catch can, isnt a water seperator for a compressed air system a better idea? its made for high air pressuer to pass through and it will seperate the liquid, from my research, most people say all they end up catching is fuel and methanol(if you spray it) because thats what ends up in your oil from the blow by.

so your saying that the smog pump wont keep up at wot? i was hoping to pul a vacuum all the way through. why would this kit use pcv valves if not needed? the fitting in the exhaust have a one way valve on them to prevent back pressure so thats not the reason. http://www.summitracing.com/parts/SUM-120108/ im thinking they just sue them as the easiest way to hook up a big hose to the valve cover for cheap, those particular pvcs dont look like they would have any restriction like a stock type pcv.

i read a thread on some other forum where a guy set up an evac sutup on a turbo buick, he said he had to use the pvcs becasue the vacuum pump pulled too hard, it was pulling strait oil or sdomething... i bet he had no baffles in his covers, he said he was making very high boost and he was pushing oil everywhere, leaks from every gasket, and the smog pump stoped his problem completely. he used the water seperators for a compressed air system, thats where i got that idea, it seems like a really good one, but it may cause restriction.

so basically, i guess my biggest are of confusion is how much vacuum do you need? im confused how to set this up becasue i dont really know what im shooting for. can i have too much vacuum in the crankcase? or is there no such thing?

chevy1500z71

this is my main source of research, cant find much info on the subject, this thread covers it halfway decent.
http://www.turbobuick.com/forums/gen...-pump-how.html

ill probably do a write up on my setup once i figure out what im doing to shed some light on the subject for other people. i can hook my boost/vac gauge up to it temporarily to get some readings, if the lt-1 smog pump is garbage(seems to be the popular choice), ill let everyone know.

im reading here on another forum that you cant run an evac system all the time or it will ruin your rear main seal. i cant hardly believe this, i would think this would help your rear main seal last longer... it was on a mustang forum lol

chevy1500z71

right now i think what ill do is run the lt1 smog pump wired to my methanol pump, so itl come on with boost. ill run a line from the driver side valver cover to a seperator, then the pump, out of the pump to under the truck, no catch can, that's for when you put it back into the intake. the passenger side cover will still have a breather.

im pretty sure you need a breather on one cover otherwise it would circulate fresh air in.