BIGASS Engine vibe after repair..

DamageINC · May 20, 2008

Ok so I posted that topic about the short bust that ended up getting a dummy plug in the oilrail for a High pressure leak..

I finished the van/bus early yesterday. Let it idle for a long while, shut it down, gave it a few re-starts - perfect. Went out an hour later and took it to lunch, drove beautifully, brought it back, let it idle all day until 5:00 when I left. Fired up at the end of the day too.

I get in this morning, crank it over - it partially hydro-locks right here in the lot, but the starter had enough nuts to crank through it and, after 2 or 3 more sloooooow chugs through the crank cycle, it started up.

And smoked out the entire city I work in.

Now I have a SEVERE engine vibration that can barely be felt at idle, but once you get on the gas at all (park/neutral or in gear) and the rpm's come up, it will shake your teeth out. I swear it's gonna rattle one of the 7 mirrors right off the bus.

Relative compression is perfect, power balance is spot-on, and I don't have any differences in my MFDES pid when cancelling out injectors - the result is the same with all 8 of them.

Standing on the gas creates a lovely cloud that would have worked nicely in the conclusion of the "highway scene" in the 2nd Matrix movie.

Reeeeeeeally looking forward to what my SM has to say about this.

Dave

Tony302600 · May 20, 2008

That doesn't make any sense. You didn't take any injector's out?

DamageINC · May 20, 2008

Wow.

Ok, so after the whole smoke show this morning, I buttoned up a couple loose ends with other RO's and got back to this thing.

Go over power balance again - everything's fine... decide to take it down the street for a bit.

Watching my pids, turn onto the highway - instantly starts *billowing* the nasties, thickest grey smoke you've ever seen from the tailpipe. Very low on power but not running rough, just shaking from the engine vibration. I get maybe 1/4 mile down the road when I lose my throttle input... rpm's start dropping, I look at my PDS to see that ICP has gone down to like 400psi. I figure it's gonna die, so I turn in to our sister location and sure enough it craps out right there on the drive-in.

I crank it, and although it's "firing" and sputtering, it doesn't have nearly enough ICP to even consider squirting the injectors. I look at the cluster - I don't even have base engine oil pressure. But somehow, it fires up and pukes a giant cloud of smoke again.

I let it idle for a few minutes, and decide to turn back around and head to the shop again.

Turn back onto the high way and the engine sounds like it's about to -explode- ... some of the gnarliest engine knock I've ever heard, I thought I was gonna have a piston come through the dashboard. I back off the throttle and dceide that I'm just gonna limp it back to the dealership.

Not quite.

LEt off the pedal and the rpm's keep climbing. Next thing I know I shift it into neutral and the revs are through the roof. Turn the key off and the bastard just keeps running, screaming away at around 3,500 rpm's. I literally drove this thing back into the shop, on the brakes, a good 600 feet across traffic with the key off.

Naturally I found a delicious fuel/oil cocktail in the intercooler and charge pipes. I pulled the new injector out to find a TIIIIINY little tear in the black (upper) o-ring, so I'm assuming that's the cause of the problem. As for now I'm going to reseal the whole bank but I'm not convinced that there isn't any base engine damage with the hydro-locking and the fact that I'm having a hell of a time building base engine oil pressure (according to the gauge).

Plus, the thign sounds like a damn maraca now.

Dave

Brad Clayton · May 20, 2008

That must have been a wild test drive. My eyes would have been bugging out of my head.

snw blue by you · May 20, 2008

How'd ya get it shut down?

I keep the extinguisher close by for just that, course don't do ya much good on the road test.

DamageINC · May 20, 2008

It just ran itself out of fuel, I'd guess... the oil level got prety high but for whatever reason it finally just puked out. I am gonna have to pull the intercooler out and clean it, just to put it back in (along with putting the rest of it together) again and HOPE that the bottom end's ok.

Think I'll get paid for it all?? Hehe I'm not sure of it yet.

Dave

kevin phillips · May 21, 2008

the one 6.0 i had do that was wasted after the runaway.it ran for 10 mins or so with the key out and it toasted the pistons.hope yours is ok.

F350SD55 · May 21, 2008

I had one that did that after a replacing all the injector orings. One of the top orings came out of its groove and slid all the way to the top of injector. Massive fuel leak into the crank case. Had gray smoke and run away also. I drained over two quarts of oil/fuel out of the intercooler. I was able to find the leak quickly with the valve covers off and using IDS to turn the fuel pump on. I don't know why the oring moved out of its proper place.

DamageINC · May 21, 2008

To be honest, and kind of a dick, I hope the engine's trashed. Maybe it's masochistic of me to actually WANT to have to put a 6.0 in a bus (no body-off possible) but for some reason it'd just make me happy to have the worst-case scenario pan out in this particular situation.

Dave