So since I got my truck back with the Flux sticks I have only been playing around in town. Yesterday I went out to a less traveled stretch of road to see how strong it felt into 4th. One of the things I noticed is that when 4th hits it makes about 50lbs of boost. It only hit about 45psi before. I also now have a billet input and so I was doing 15-20psi launches rather than the 4-5psi ones I have done before. (That's way fun by the way) So after a few runs I went home. Let the truck sit in the drive for a couple hours as I was going to leave again later. I go outside and there is an oil spot 5" in diameter. It is continuing to leave small spots after every drive and seems to be a little worse if I get on it a little. It coming from the inspection cover - which I have not pulled yet to inspect things more closely. Seems like it would be the rear main seal. I pulled the dipstick. The oil had climbed clear up the tube and the entire dipstick was covered. My first thought was fuel in the crankcase. I wiped it down and checked the level and it's actually a 1/2qt down. So what is going on? Lots of guys see more than 50psi, so I have a hard time thinking that could be the problem. It seems like it has way too much crankcase pressure or something. What would cause that? Could I have tweaked things enough with a 20psi launch to cause a problem with the rear main?

 

first thing that comes to my mind is worn rings letting boost come by and causing blow by, hence excessive crankcase pressure. someone correct me if I am wrong.

 

This wasn't a gradual thing. It was not leaking and suddenly it is. It only has 58k miles on it.

 

after you wiped off the stick, was the oil level at a normal level and not overfilled?

 

Do you have head studs? If you do, did you or someone remove the extra aluminum from the valve cover spacer? The back center stud will hit and allow oil to come out. Look real high on the block by the head and see if you see oil. Perhaps the bolts weren't tight when it was put back on after your injectors???

 

Here's my thoughts... there is a filter type device on the inside of the plastic valve cover. I know it has something to do with crankcase breathing. And I'm pretty sure I saw the name Fleetguard on it. I have never read anything about it or heard anyone mention it. Now that your making more boost, you're creating enough crankcase pressure that cannot be contained by this filter or the filter is dirty and your crankcase is venting out the tube and blowing onto the inspection cover. I've had this happen a few times and it wasn't the rear main because I checked. It is strange about this filter thing on top of the head...?
Also, we have 359 cubic inches of displacement on the bore/stroke side of the engine and the same is being forced into the crankcase. The more you push it, the more it's gonna push back. That pressure has to go somewhere. It's a very harsh environment in that crankcase...

 

I don't normally bump my threads, BUT....
Anyone else?

 

I get more blow by after an extended period of flogging...wipe of the bellhousing and watch again...

Air blows the blow bye everywhere...I have never had a look at my dipstick right after either...so I have no idea whether that is normal...

A blown head gasket could pressurize the oil...look in the radiator? How does it run still?

 

Not sure about these motors but I was boosting my Mustang to about 17#'s. After a run one night I was pouring oil out the rear main seal. Looks like I was boosting the crankcase also.

In the end, I needed a new seal and a one way valve to be put in line on one of my emission hoses. HTH

 

Well, 1 carwash, 2 cans of brake cleaner, and 3 test drives later....

A cracked dip stick tube. When one of the guys who's been working on my truck needed to have the dipstick tube moved over they apparently only unbolted it from the intake horn and not the bracket down by the filter housing and then pushed it out of the way. Right above where the bracked is welded to the tube, it cracked. Pulled it out and braised it and we'll see how it goes - should be good. Over all, it cost me about 3.5 hours which I'm not too happy about, but I guess it's better than my original thought of the rear main seal.

 

hopefully it was just that was it up to temp Its rare but and im not sure what kind of seals ats uses in there turbos but on the engines i work on if the guys dont letum warm up and hammer on them the seals dont seal up and you get boost through the oil drain but thats uasly seen on very well used and abused logg trucks and the like by the way how do you like the 3000 was intrested in one but you never hear about then on the threads