Chevy and GMC Duramax Diesel Forum banner
  • Hey Everyone! Enter your ride HERE to be a part of this months Ride of the Month Challenge!
1 - 16 of 16 Posts

·
That One Guy
Joined
·
7,421 Posts
Discussion Starter · #1 ·
Hey guys I was under my truck and checking out my 2nd fuel filter when I notices some oil on the bottom side of my motor and I think its coming from the oil blow by tube. Should I be worried about it or no?

Thanks
 

·
Registered
Joined
·
487 Posts
Whats your dip stick say? If its a little high I wouldnt worry, but if its low then I would check to see if theres pressure when you remove the oil cap while running. Just a thought.
 

·
Vendor
Joined
·
3,528 Posts
Its normal on LB7's
 

·
NewEST Spinny Thinggg
Joined
·
4,291 Posts
mine has been spittin oil from right where the bell housing n engine meet...i think my rear main is leakin cause i had some TC vibration with my old TC...but im less familiar with LB7's...i wouldnt worry as long as there isnt any pressure
 

·
That One Guy
Joined
·
7,421 Posts
Discussion Starter · #5 ·
I don't lose too much in between oil changes. I'll have to see if there is pressure when I open the oil cap.
 

·
Registered
Joined
·
487 Posts
I had the same problem on mine after my last oil change and found I had overfilled it by about 1/2 quart. Maybe nothing to worry about. I dont lose anything between oil changes either so I was worried when I first saw it.
 

·
NewEST Spinny Thinggg
Joined
·
4,291 Posts
I lost 2 quarts so far between changes...this weekend its all comin back off to change it...if it was somthing big it would prolly pop the dipstick out...have you checked the PCV sometimes they get gunked up n stuff which can built a little pressure
 

·
Premium Member
Joined
·
8,815 Posts
Mine does it too...not a lot..just makes a mess. I dont seem to lose oil..no fuel in the oil. Called the dealer on mine and they said injectors right a way...I told them BS...my balance rates are good and no fuel in the oil. They said to try and change the oil cap....didnt help...still does it and not all the time either.
 

·
That One Guy
Joined
·
7,421 Posts
Discussion Starter · #9 ·
No I haven't checked the PCV I'll check that out also I figured it wasn't anything too big but I just wanted to see what everyone had to say about it.
 

·
Premium Member
Joined
·
8,815 Posts
I lost 2 quarts so far between changes...this weekend its all comin back off to change it...if it was somthing big it would prolly pop the dipstick out...have you checked the PCV sometimes they get gunked up n stuff which can built a little pressure
Federal emissions LB7s dont have the PCV like the later models...just vents the valve cover... I read where there was supposed to be a "box" by the alternator that would allow oil to drain back into the engine, but i cant find it on mine.
 

·
NewEST Spinny Thinggg
Joined
·
4,291 Posts
yeah i knew they didnt have the same setup but still thought getting gunked up might be possable cause all mine has is lines that vent straight out n they slowly build up goo from the oil vapor passing through
 

·
Premium Member
Joined
·
8,815 Posts
Those diaphrams look to be quite a pain to remove and clean though... I do need to figure something out for mine.
 

·
NewEST Spinny Thinggg
Joined
·
4,291 Posts
can you replace them maby pull em and put a small breather in the hole...IDK alot about the LB7 models since they are setup so dfferently
 

·
Premium Member
Joined
·
8,815 Posts
the diaphrams are separate from the breather in the front. From what I can tell the lines come out of the valve cover to a T and then to the front down to the blowby tube in the front...
 

·
Registered
Joined
·
455 Posts
If these diaphrams r bad, can it cause the smoke out of the breather tube?
 

·
Registered
Joined
·
455 Posts
Anyone removed or replaced the diaphrams? Can they cause the smoke? Also is it a bad idea to put a tee in the breather tube and route that back into the air intake somewhere? If u could do it just right to keep the oil out.
 
1 - 16 of 16 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top