Yellow Bullet Forums banner

1 - 20 of 31 Posts

·
Registered
Joined
·
16 Posts
Discussion Starter #1
Hi Everyone, my is name is dustin. I'm new to this site. I have lots of friends who use this forum, and it is very helpful for them. Lots of very knowledgeable people on here, hopefully someone can help me with my issue.
This is my first drag car, but I am not new to cars, I have a 93 s-10 with 383/th 400 drag truck. Engine specs are. 383, 13:1 cr, protopline heads 235 runner, 64cc, 2.100/1.060 valves. All forged lower end, MO town dominator intake.
I am running a header evac system. From the very beginning after I make a pass, I was getting a small amount of oil coming out of the valve cover gaskets, and the breather grommets.I've tried changing the valve cover gaskets, I have the bolts as tight as I can get them. It does not leak oil until I spin the motor up high doing a burnout or a test pass. Recently I changed my motor over to alcohol, ever since then I have been having issues like crazy, it started leaking a lot more oil. People are telling me that alcohol makes more case pressure and stroker motors already have a lot of case pressure.so we came to this conclusion that I need to run at a oil breather tank as well. I bought a Moroso oil breather tank and ran a hose from fuel pump plate to breather tank -10. I made a test pass out at my work, did a few burnouts and that whole breeder tank Filled up and was overflowing out of the breather filter within 10 minutes. I'm at a loss here. No one can give me a much aDvice. I'm going to check the one-way valves on the evac system tonight. Other than that I am lost.I do not seeing it be major internal issue. The motor is brand new probably have only 10 passes on it.hopefully someone can help me plz.maybe I need to remove the breather tank hose up to the valve cover?
 

·
Registered
Joined
·
625 Posts
Are there mufflers behind the evac system? That low spot for the breather may be too low. Bad ring or rings. Head gasket leaking into the lifter valley.
 

·
EFI/N2O JUNKIE
Joined
·
17,905 Posts
Are there baffles in the valve covers? Many have too much restriction. Honestly, test the car with normal breathers and let the engine breath. You don't need a special breather tank for that engine.
 

·
Registered
Joined
·
6,482 Posts
It'd be nice to see how you have things configured .... chance of any pics? Whereabouts on the covers are the breathers located and what type of grommet? Baffles? If they(grommets) are closed off at the bottom w holes in them, you need to open them up
 

·
Registered
Joined
·
16 Posts
Discussion Starter #5
The grommets are straight through. No baffles if I. Look into grommet I can see the stud girdle. I will get pics ASAP tonight
 

·
EFI/N2O JUNKIE
Joined
·
17,905 Posts
The grommets are straight through. No baffles if I. Look into grommet I can see the stud girdle. I will get pics ASAP tonight
That is what you want.

What valve cover gasket? I use the Fel Pro blue gaskets, they are rubber with a metal shim between them, last forever, Moroso also makes them.

Check the one-way valves, make sure they only work in one direction.

I run that stuff with mufflers and have no leaks.

Open headers, you should have NO issues. Could be a ring sealing problem.
 

·
Registered
Joined
·
4,014 Posts
I would do a compression check and Leak Down test to insure the motor was solid before beating my head against the wall any further.
 

·
Registered
Joined
·
16 Posts
Discussion Starter #9
I do have the good blue felpro gaskets. I'll check the one way valves. Maybe I'll just try breathers on the valve covers with no evac system?
 

·
Registered
Joined
·
1,747 Posts
I had a 350 once that I put a breather with a pcv nipple on to relieve some crankcase pressure, blew the breather off and smacked the under side of the hood. Ended up being a broken ring land on the #2 piston.
 

·
Registered
Joined
·
1,747 Posts
Are you sure the nipples going into the headers are at the proper angle? I bought some used headers with an evac and the nipples were closer to straight up and down than the 45 degrees they are supposed to be, had to tweak the angle on the inside of the collector.

But you still should not be getting that much oil, you need to do a leakdown test, or atleast a compression test to see what cylinder is causing the problem.
 

·
Registered
Joined
·
1,821 Posts
I had the same thing happen and it turns out my rings are shot. Compression test is good but leak down test shows that it's at 40-50% leakage. It's a fresh engine, too. The rings didn't seat correctly. Yours is probably just worn.

Go to Harbor Freight and get a cheap leak down tester for $39.95 and check out what is really going on with the rings.
 

·
Registered
Joined
·
965 Posts
I would Do a leak down test.Look down the oil drain back holes in the end of the heads and make sure they are not restricted.A lot of motors that have been sleeved and stock 400 blocks have blow by problems.
 

·
Registered
Joined
·
16 Posts
Discussion Starter #15
Cyl 1=200
Cyl 3=180
Cyl 5=180
Cyl 7=180
Cyl 2=180
Cyl 4=180
Cyl 6=190
Cyl 8=200

These are compression test results, I do not have a leak down tester at the moment
 

·
Registered
Joined
·
2,649 Posts
Compression wise that spread isn't horribile. Time to go up top for a leakdown.
I would run a set of VC WITH baffles in them first and see what happens.
A lot of oil gets slung around in there at high RPM. I had a similar issue with some shallow Eddy VC's and vortec heads.
 

·
Registered
Joined
·
1,259 Posts
check the one way check valves.. some of the KIT valves are garbage and dont "suck" as easily as a stock replacement from checkers for smog systems.. remove the tubes going to valve covers and stick a piece of paper up to them at idle.. If the paper doesnt get pulled to the tube something is wrong..
 

·
Registered
Joined
·
16 Posts
Discussion Starter #18
I don't see how baffled valve covers would help me evac more pressure out? If remove the oil tank and go back to just evac tubes, I'm still going to be getting small oil seepage from valve cover and grommets. I just want to catch the problem before I blow out a rear main seal or something from the pressure. I will do a leak down tomarrow
 

·
Registered
Joined
·
16 Posts
Discussion Starter #19
Ok guys. Finally got around to do a leak down test.. everything looks good to me.
1=25%
3=25%
5=20%
7=25%
2=18%
4=35%
6=20%
8=22%
I'm at a complete loss. This makes no sense as to why the oil tank filled up in 10 minutes? Hopefully somebody can help me. The motor runs perfect, it sounds great. No smoking. I just don't get it
 

·
Registered
Joined
·
6,482 Posts
Ok guys. Finally got around to do a leak down test.. everything looks good to me.
1=25%
3=25%
5=20%
7=25%
2=18%
4=35%
6=20%
8=22%
I'm at a complete loss. This makes no sense as to why the oil tank filled up in 10 minutes? Hopefully somebody can help me. The motor runs perfect, it sounds great. No smoking. I just don't get it
If it were my engine, I'd be wondering why my % is any higher than 15 .... You say it's newer engine I believe, how much oil pressure does it have ? Maybe excessive amount up top ? Using oil restrictors ?
Where did you get the engine from? Who built it?

Is the evac system a Moroso? I would not trust the knockoffs, and the breathers are most likely leaking at the crimp underneath where the 2 halves are joined(if that's what your using). Clean and seal that crimp with RTV

Did you comfirm you have draw/suction at the end of the lines from the valves ? Are you running an open breather/vent anywhere off the crankase ? A vent on the can ?

It's a good idea, even if only temporary to run clear line on the evac setup when having issue like this, as you can see where the oil is coming from ...
 
1 - 20 of 31 Posts
Top