I recently rebuilt the top end of my motor, installed a V1 A-trim along with mostly supportive mods, and have been daily driving it. Thing has been RUNNING AWESOME...no traction until 60+...anyhow...last night after flogging the thing, i smelled oil burning and noticed my breather tube had come lose out of the valve cover, and oil was just flinging onto my manifold...no biggie...re-made re-routed my breather tube today...test-drove it, everything's fine, doesn't pop out anymore...

then later today...I was drifting around a turn-about...came home...popped the hood and checked everything out..all looked good...got in, started the car...drove 100ft...turned around...got on it a lil bit in 1st..and it sorta stumbled, like bad gas stumble...so i just pulled right back in the driveway...popped the hood...and oil everywhere around the BOV. I'm thinking it could be one of too things...

A: my breather hose which is routed to my intake tract pre-supercharger is rather effective and when I was drifting around the turn-about revving between 5-6K for that long it may have been able to develop a pool of oil right below the supercharger...and now when you finally give it enough throttle to suck up the oil its just sputtering out of the BOV and into the motor causing it to stumble.

or

B: Supercharger seals are blown. Now I'm relatively new to forced induction, and have never seen what blown seals do/look like. So if someone with more experiance/knowledge than I can give me some insight on this, I'd much appreciate it. I have yet to pull the car in the garage and start taking her apart to check this stuff out...but will be doing so tomorrow.

Any/all help will be appreciated...Thanks,


oh BTW...my kit is not setup like a standard V-1...I modified some things, which is why I have a Tial BOV that exhausts to atmosphere and not the plastic by-pass valve, maf is BLOW through, etc etc...I'll post some pics if it'd help soon as my server is back up 'n running...other general info: was boosting to 7psi at 6K...

 

mmm'k...well i just jacked it up and pulled off the air filter, and the flexible air ducting (the crap tube that looks like dryer hose)..and a decent amount of oil poured out right were the breather dumps into the air duct....so I disconnected the breather connected a new air filter to the supercharger and started it...lots and lots of crankcase gases were coming out of that breather hose, and not much oil was coming out of the BOV, a small amount, but I think its just the residual oil left covering the supercharger and intake tubing, not nearly the amount that was coming out earlier...

so...I think my breather hose was too effective at allowing oil to jump from the valve cover to the intake tube, where its prolly been pooling/building up for the past 2 weeks...I'm gonna let it drip dry itself tonight, then tomorrow run the breather hose to a catch can instead of the intake tube...clean everything...then flog it and see if it repeats itself or not...oh, where can get a hard-tube to replace that dryer duct looking tube? or just a new dryer duct...this old one is soaked in oil and I think the paper is about to tear because of it...if possible just point me to someone that sells one and I'll be purchasing a.s.a.p...thanks,

 

I think when the supercharger seals go out, so does the boost. A friends S-trim started leaking oil into the intake, then quit making boost.

If you can find a muffler shop with 3.5" tube, they could build you an intake.

 

k, good....yeah no she's definately still building boost...I'll know tomorrow if my assumptions are correct. Curious how much crankcase gases normally flow outta our breathers? I'd be more worried about it being excess but I did a leak-down test on every cylinder when I set my valve lash, and they were all at or below 10% which blew my freakin' mind....almost 160,000 miles on the stock bottom end...

exhaust shop...good thinking...I'll prolly swing by one tomorrow and see what they say...

Thanks,

 

sounds too me like you have motor issues espcially raping it like that with so many miles on it under boost maybe you should look into piston/ring issues

 

Broken ring lands.

 

what's the most effective way to test/check for piston/ring issues?

would another leak-down test be a good place to start, then if I find a dead cylinder, or any red flags I should plan to tear it down?

 

With the engine idling and the oil fill tube open, does oil vapor puff out the opening? If so you have broken ring lands (common issue on SC'd F-bodies).

 

hmm...well I rerouted my breather to atmosphere today...cleaned out all the intake tubing...then flogged it...run's super strong again...back to normal...seeing full boost of 7psi...

here's the thing...I can pull off my oil fill cap and yes there are some vapor puffs that puff out...but if I actually had a broken ring land, it seems symptoms would have to me more severe...for example...I don't burn oil...exhaust burns clean...seems if I had a broken ring land I'd for sure be getting blow by into the cylinder and that'd become very apparent in the exhaust smell/color. Also, I don't think I'm down on power at all...

Just curious...I mean...this motor has some miles...I'm assuming its normal to expect some added crankcase pressure with 160,000 miles...ring lands, logically to me, seems unlikely with my symptoms, there just not severe enough...unless its possible to have a broken ring land, not burn any oil, and not have a noticable drop in power...but this is why I post on this board...I lack the experience you guys possess...

Thanks for the feedback...keep it coming...

 

If you pop the oil fill cap and see puffing, that's commonly referred to as the the "chug-o-death".......a healthy LT1 will have NONE whatsoever. Allow me to welcome you to the rebuild club!

And yes, it is possible not to perceive a power loss with busted ringlands, but you'll definitely start consuming some oil and it will be down on power. I drove my car another 20K miles after the chug started and even added nitrous and beat on it regularly. Others have had the motor crap out the next day...either way, it sounds like you're on borrowed time and looking at a rebuild. Go wild...the rest of us did!

 

haha now there's some advice I can drink too....alright...it's all making sense now...

chug o' death...nice

Welp, I intend on driving the hell out of it like usual...that's why I built it...I'll just start looking for a built shortblock most likely, and keep 'er on a stand in the garage...then when this one finally lets go I'll swap what doesn't get destroyed and start all over again...

Thanks for the help,

 

Aint no big thing. Kinda looks like this inside is all...

 

I've broken several sets of ring lands and never had it smoke out the tail pipe. Do a simple compression test and it'll show up.

 

I had the chug o death for over a year before I tore it down. It still ran strong as an ox. I think a had 4 or 5 bad pistons.

 

Be sure to check and clean the airfilter to, becouse if it is cloged it will suck the oil out of the supercharger, at least the Paxton SN types do that.