burning oil problem

[bart]

right now im burning around 1-2 qts every 2-3 weeks. which is right around 800-1200 miles. i get a huge puff of smoke on startup, but never really see any when i get on it or anything like that. but im sure its there and i just cant see it. the motor was been rebuilt last summer, has right around 15-20k miles on it. im pretty sure its not the seals or anything like that. but i could be wrong. now ive been told that it has something to do with my PCV system and to plug the nipple at the valve cover. im not touching anything till i get some conformation on this.

now the reason i was told it was the PCV was because im running an explorer intake, and fox body covers, with no baffle. when i pull my upper off, there is oil in between the intakes, more than id like to see too.

ive also heard that 5.0's are supposed to use about a qt every 1k, but im losing it way too quick here. like i added a qt not this past friday, but the friday before, and yesterday the motor was making some nice chatter. pull the stick and i was 2 qts low. id like to get something solved or at least slowed down. thanx for any help

Bart

 

[HISSIN50]

i would not plug anything with the PCV. as Michael has explained to me (if i dont mess it up), PCV is bi-directional. loss of oil through PCV is mostly from blowby, i think. and with a fresh mill, you should not have much.
you could rig a catch can and run a filter (like a fuel filter) so that you can see how much oil is really coming through the PCV. some even put a drain on the catch can, so it is more of a closed system.

i know others will have some good info to help you out.

good luck.

 

[25thmustang]

Dont rule out blow by or ring issues. My shortblock had 15,000 on it when the rings went south, and in a bad way. My issue was gas in the oil after doing some work to the car. Was there ever a time with the new motor when it had issues starting (just cranked and wouldnt turn over?) or a chance gas could have gotten into the oil? I know my car was really bad right before it needed a rebuild, but it went from good to bad VERY fast. Check the compression in the cylinders to rule that out!

 

[bart]

Dont rule out blow by or ring issues. My shortblock had 15,000 on it when the rings went south, and in a bad way. My issue was gas in the oil after doing some work to the car. Was there ever a time with the new motor when it had issues starting (just cranked and wouldnt turn over?) or a chance gas could have gotten into the oil? I know my car was really bad right before it needed a rebuild, but it went from good to bad VERY fast. Check the compression in the cylinders to rule that out!

ok im about to go borrow my friends comp tester. what should it be if all is in working order?

and what is blow-by, ive seen this word like 500 times and have yet to figure out what it means.

 

[25thmustang]

Blow by is oil getting by the rings, and out the exhaust... A little is ok from my understanding but a sign the rings are begining to go.

As far as compression testing, make sure they are all reletively close (all the cylinders) keep track of each and write them down! As far as the exact numbers too look for I am not exactly sure (someone should know) as I have yet to compression test mine.

 

[HISSIN50]

also, for a compression test, do wet and dry. pull the plugs (all before beginning testing), crack the throttle wide open. disable the ignition.

do dry first. then add a little bit of oil to each cylinder and redo it. if the numbers jump up a lot with the wet test, that suggests the rings are worn (the oil helps them seal). this would be your blowby. if the wet and dry numbers are real close, then i would look elsewhere.....

BTW, a leakdown test is more comprehensive, but probably not needed until after the compression test.

good luck.