Did a burnout, got engine knock...

[Oskar]

yepp, just got my license plates and took the first trip in my new truck.. but the happieness didn't last long, made a small burnout, just held it with the brake until turbo spooled up abnd let of the brake, wheels started spinning and when they gripped i heard something strange and slowed down, then there was a heavy knock coming from the valve cover area, sounds like it's only on one cylinder, cracked all injctor lines and it's not a sticking injector, so today i took of the valve covers, felt that the valve play on the exhaust valves was well over 1mm, nearly all the pushrods seems to be slightly bent, i don't know how much is too much but if i rotate them i can see that they're slightly bent, something like 0.2mm off.
i listened to all thecylinders through a stetoscope and the knocking comes from no6 so i disconnected that cylinder by loosing the inj. line, removing the rockers and pushrods and started it, the knocking was gone.. so it seems to come from the valves, but how the hell is that possible? and why is the valve play on all exhaust valves more than double over spec.?

one more thing i noticed, when the engine is running, it seems that compression is seeping out around the head bolt going through the rocker pedestals, on all cylinders, BUT what makes me really confused, is that it seems like compression is going through the material in the pedestals too!!! there is some tiny bubbles coming through the top surface of the pedestals! this just don't seem to be right!!!

any ideas what the hell could cause this knock that came so suddenly?
and is it normal to see compression seeping righ through the material in the rocker pedestals?

[oldestof11]

Burst a headgasket?

[BC847]

- Is yours an automatic trans? The flex-plate may have cracked (common for the OEM flex-plate), and the popping of the crack is coinciding with cylinder #6.

- Lube oil for the rockers is conducted to them via the head bolt passage in the rocker pedestal. That same oil first comes up from the block, and through a short passage in the head-gasket. It's possible for the head gasket to fail and allow combustion gasses to get into the oil passage of the gasket and blow bubbles as you see. But I wouldn't expect to see it at all the pedestals.

[Oskar]

yes it's automatic, i'll check the flexplate from undernearth.

i'll try to make a video of the bubbles and knocking.
i'll also make a compression test as i remove all injectors today to pressure test them.
what compression pressure should i expect?

[Oskar]

here's a video of the knock: http://s73.photobucket.com/user/_chevro ... 9.mp4.html

compression was between 22-24 bar (330-350psi) and even between all cylinders, injectors did pop off at only 200bar, the spec says 245 but all of them was equal so that can't be the cause.. flexplate looks good what i can see from undernearth.

is it possible to take off the oil pan with the engine in place?

pleas give me some good ideas!! could it be as easy as the lift pump?

[PToombs]

IIRC, if the flex plate is cracked, you usually can't see it unless it fails completely or you pull the trans.

[Oskar]

IIRC, if the flex plate is cracked, you usually can't see it unless it fails completely or you pull the trans.

now i removed the bolts between the plate and converter and started the engine, the knock is still there, so it can't be a cracked plate either..

a rod bearing knock would have sounded more under load than coast, and the oil pressure would have dropped, it goes up to half scale at warm idle, no blowby, starts immediately and has only 175000miles... what the hell can it be???!!

[Mark Nixon]

Pull the valve covers and check for broken pushrods or rocker arms.
Trust me, it happens.

Mark.

[Mark Nixon]

...i listened to all thecylinders through a stetoscope and the knocking comes from no6 so i disconnected that cylinder by loosing the inj. line, removing the rockers and pushrods and started it, the knocking was gone... ?

Okay, by re-reading this and listening to the video closely, I am of the opinion it's bottom end related.
Re-do the procedure above, except do so by ONLY loosening the injector line, leave the rockers and pushrods in place and open the injector line several times to determine if the noise comes and goes.
If the noise is gone when the line is loosened, then it's piston/connecting rod related.

By eliminating the fuel, (or spark on a gasser) to that cylinder, you take the pressure of combustion away from the piston/rod combination, in so doing it lessens or completely silences the noise.
In your video, the noise sounds like any other light rod knock I have ever heard in a Cummins.

Mark.

[Oskar]

...i listened to all thecylinders through a stetoscope and the knocking comes from no6 so i disconnected that cylinder by loosing the inj. line, removing the rockers and pushrods and started it, the knocking was gone... ?

Okay, by re-reading this and listening to the video closely, I am of the opinion it's bottom end related.
Re-do the procedure above, except do so by ONLY loosening the injector line, leave the rockers and pushrods in place and open the injector line several times to determine if the noise comes and goes.
If the noise is gone when the line is loosened, then it's piston/connecting rod related.

By eliminating the fuel, (or spark on a gasser) to that cylinder, you take the pressure of combustion away from the piston/rod combination, in so doing it lessens or completely silences the noise.
In your video, the noise sounds like any other light rod knock I have ever heard in a Cummins.

Mark.

Hi.
when i cracked the injector lines one by one, i couldn't get rid of the knock, it was only when i removed the rockers and pushrods it went away. also, i noticed that all pushrods, both intake and exh. was slightly bent, not much at all, but one could see that they weren't perfectly straight when rotating them.

could it maby be anything cam-related? like lifters or cam lobes?
if a rod bearing is worn, wouldn't the oil pressure drop then? i didn't notice any change in oil pressure when the knock came.

again, has someone managed to get the oil pan out with the engine in place, or slightly lifted up, or do i need to remove it compleatly?

[Mark Nixon]

A pushrod is bent if it wavers when rolled on a flat surface, eyeballing them isn't going to show much.
Even a moderate rod knock generally won't affect oil pressure on a Cummins.

IIRC, you can get the oil pan out of the chassis by lifting the engine as high as possible (without causing things to bend or interfere), by removing the fan shroud and the lower isolator (engine mount) nuts and LOOSENING the upper isolator nuts.
It may be necessary to unbolt the pick-up tube and let it fall in the pan to remove it, which is 4 bolts, 2 near the front of the block, 1 near the sump end and 1 about halfway between.

Mark.

[Oskar]

Hi, Just want to let you know that i found the fault, some kind of metal piece (looks like a piece of a steel washer)
got sucked into the engine and smashed into #6 piston, hopefully the piston is OK if i only remove the piece and grind away any aluminium burrs.

but i need to find where that piece came from! it looks like some hard steel piece, like a bit from a piston ring, but it can't be a ring since there isn't any scratches in the cyl. walls at all..
took the turbo apart but no parts are missing there, will try to check the intercooler too.

here's some pictures:







Also, another question, does somebody know what type of converter i might have? it's marked "11 161" and nothing more, the tranny was rebuild at Bob's Transmission in CA, and on the reciept it says only "replacement converter"

At this time it's a good idea to change the TC if there are better ones on the market, only thing i have in mind is fuel economy and low RPM's at highway speed (70mph in Sweden), so a lower stall speed is appreciated (also helps to keep the fluid temp down)

[RCCUMMINS89]

Hard to see, the pictures are blurry.

Not piece of the h/g by chance is it? I've seen that before.

Otherwise nothing comes to mind.

[Oskar]

It's not the head gasket either.. took a picture of the metal piece too:

[Oskar]

Where is the best place to buy a new oil pan? Rockauto didn't have it.
And what brand of headgasket should i use? RA had Felpro and Victor reinz.