Bracket Talk
Vacuum pump pulling oil LS

This topic can be found at:
https://drr.infopop.cc/eve/forums/a/tpc/f/80760912/m/3287036207

July 21, 2025, 08:44 PM
Bucky
Vacuum pump pulling oil LS
pickup toward the front of the valve cover. It pulls a bunch of oil every run. Have thought about swapping to the valley cover. It's a stroker engine with a stock style pan. So windage is probably a thing. Anyone cure this with their pump? This is a boosted application so probably even more challenging.


Foxtrot Juliet Bravo
July 21, 2025, 09:17 PM
rusty
i had mine on the front end and it pulled oil bad


honesty is the best policy,insanity is a better deffense
1.036, 6.16@ 224

July 22, 2025, 06:11 AM
Curly1
Do a smoke test and find your leak. If you have a leak it is pulling air (and OIL!) through the motor.
https://drr.infopop.cc/eve/for...912/m/7547054207/p/1


https://postimg.cc/gallery/np3zpruo/
"Dunning-Kruger Effect"
-a type of Cognitive bias where people with little expertise or ability assume they have superior expertise or ability. This overestimation occurs as a result of the fact that they do not have enough knowledge to know they don't have enough knowledge.

Before you argue with someone ask yourself, "Is this person mentally mature enough to grasp the concept of a different perspective?" If not there is no point to argue.

4X NE2 CHAMPION. 2020 TDRA NE2 Champion
July 22, 2025, 06:50 AM
Bob Payton
I have mine pull from the valley side of the valve cover. I would always suck a lot of oil up front. I had a lot of windage and reduced the amount of oil by about 1/2 quart and that helped too.


--------------------
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July 22, 2025, 08:04 AM
Bucky
There may be an oil level that will help. I’m just a little afraid to explore where that is. Oil pressure seems to be sensitive on these regarding level
The valley plate cover is separate on an ls. So putting the pickup there is a consideration.
I’ll do some leak checking too


Foxtrot Juliet Bravo
July 22, 2025, 09:32 AM
Lenny5160
My fitting is in the front of the valve cover, and I was pulling a bunch of oil. Ended up turning down the vac a bit to band-aid it.

After my engine was freshened, BOOM, whole different deal. We smeared silicone all around the oil pan rail, for one thing. Not sure if that was it, or if something else was sealed better, but there was definitely some sort of leak causing it to pull so much oil.


Tony Leonard
July 22, 2025, 10:12 AM
CURTIS REED
It's so strange that people have such different results. I have only ever pulled from the front of the passenger cover and have pulled almost no oil. It's just open ended into the cover also.


July 22, 2025, 01:11 PM
ski_dwn_it
as mentioned smoke the motor. If its sealed up it should not be moving a bunch of air. When you have a huge leak, it pulls a lot of air and oil comes with the air. Not the way they should work.

When you smoke it you will find your leaks.

Watch my other post here on smoke machines.
July 22, 2025, 04:13 PM
rusty
i should have mentioned i think mine was because of gforce from 1/4 mile shutdown and mph


honesty is the best policy,insanity is a better deffense
1.036, 6.16@ 224

July 22, 2025, 04:14 PM
rusty
that smoke tester is the real deal


honesty is the best policy,insanity is a better deffense
1.036, 6.16@ 224

July 22, 2025, 05:51 PM
CURTIS REED
quote:
Originally posted by rusty:
i should have mentioned i think mine was because of gforce from 1/4 mile shutdown and mph


A problem I will never have. Laughing Hard
July 22, 2025, 06:32 PM
rusty
maybe a 1471 curtis and all of the way to the other stripe. Big Grin


honesty is the best policy,insanity is a better deffense
1.036, 6.16@ 224

July 23, 2025, 06:36 AM
Curly1
quote:
Originally posted by rusty:
that smoke tester is the real deal


Absolutely, you would be amazed the places you get leaks. Have had leaks around cam driven fuel pump, Distributor, intake manifold bolts, China rail. Smoke test it and fix all leaks and then start looking at other areas. Some motors like SBC do not drain back oil from heads very good. Oil drain back holes and hoses in back of heads help a little.

Probably 3 things that make is pull oil. 1. Air flowing through motor it will blow oil with it. Seal it up.
2. Volume of oil up top,may need to put drain back hose and or restrict oil up top. Note, a thinner oil will drain back in pan quicker but having right weight oil where needed is more important. 3. Location of hose should be up high and away from oil.


https://postimg.cc/gallery/np3zpruo/
"Dunning-Kruger Effect"
-a type of Cognitive bias where people with little expertise or ability assume they have superior expertise or ability. This overestimation occurs as a result of the fact that they do not have enough knowledge to know they don't have enough knowledge.

Before you argue with someone ask yourself, "Is this person mentally mature enough to grasp the concept of a different perspective?" If not there is no point to argue.

4X NE2 CHAMPION. 2020 TDRA NE2 Champion
July 23, 2025, 08:35 AM
Joe C
ski_dwn_it knows smoke machines! Yes, the machine he lists does work.
July 23, 2025, 09:03 AM
ski_dwn_it
quote:
Originally posted by Joe C:
ski_dwn_it knows smoke machines! Yes, the machine he lists does work.


Big Grin Don't forget the "Diddy oil"
July 23, 2025, 09:24 AM
Joe C
And it does stink when burning!
July 23, 2025, 09:40 AM
CURTIS REED
I'm going to try this.


July 23, 2025, 03:12 PM
undacuva67
leaked it?
July 23, 2025, 11:39 PM
TOP38
The main reasons are as follows

- two much air flow from vac leaks or excessive blow by that pulls oil out
- too much oil upstairs, use oil restrictors
- bad vac port location - relocate or add a shield at the vac port

Note that placing the vac port on the front of the valve cover which many do successfully, will suck oil out if you have too much oil upstairs when you break after a run.

A good sealed up motor from both good ring seal and no other sources of vac leaks will minimize air flow and also minimize oil from getting suck in. A small amount does help the vac pump seal and live a long happy life.
July 24, 2025, 12:27 PM
Goob
How are you measuring / controlling the amount of vacuum you're pulling on the crankcase?
IIRC, that needs to be in the 8-12 in/hg range.
A baffle / filter in the cover might help?


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