destroyed piston!!
 

I had a loud knock in my engine.

The injectors where tested and where good.

Tonight we took the cilinderhead off. And we found out that the piston in cilinder 3 is broken.

http://i90.photobucket.com/albums/k2...8/DSCN0954.jpg

http://i90.photobucket.com/albums/k2...8/DSCN0956.jpg

http://i90.photobucket.com/albums/k2...8/DSCN0957.jpg




How can this happen?
Could it be that this is because of the Banks Six-Gun?


The word FRONT on the pistons are on all 6 not in the midle.

This is cilinder 6 that one had a few little marks. So proberbly with this piston would happen the same later as on piston 3!

http://i90.photobucket.com/albums/k2...8/DSCN0958.jpg



I hope you can help me!

Roel

#3 to me looks like it was getting too much fuel there is a lot of carbon on that one compared to #6. It also looks like a valve may have touched the top of the piston on the right side. I would re-evaluate the injector in #3 as well as check the valves in that cylinder. Good luck, and keep us posted.

If there was to much fuel it should have make white smoke shouldn't it???
There was no white smoke. I've heard that there could be less fuel. that man told me, it could get to hot then also. Is that right???

And one man told me it also could be a problem with the spraying of the oil to cool the cilinder. Is that also an option?


And if there is a problem with to much or to many fuel could that be thanks to the Six Gun??

Looks like you might have dropped a valve seat, causing the valve to hang open so as he piston could hit it. The extra carbon is probably because the cylinder has been misfiring because of the valve problems, and lower compression. Pull the valves out of the head on that cylinder, and check those pressed in seats. I was kind of disappointed to find they used pressed in valve seats.

The valves would be a good thing to check like sprinter said.

I'm not sure if the banks set up raises rail pressure or not, but if it does it could have caused the injector to crack and dump more fuel to that cylinder. Too much fuel when the engine is cold would make white smoke, when warm it would make black smoke.

There was no white smoke and there was no black smoke. (not more then normal)

There some pics of the head. It doesn't have any marks that the piston hit the head or the valve's. For as far as I can see.(i'm not an expert)

http://i90.photobucket.com/albums/k2...8/DSCN0964.jpg

http://i90.photobucket.com/albums/k2...8/DSCN0967.jpg


An some pics with the piston in high posision.

http://i90.photobucket.com/albums/k2...8/DSCN0968.jpg

http://i90.photobucket.com/albums/k2...8/DSCN0969.jpg

It looks like there may have been some contact with a valve. I know the valve doesnt look like it, however that 1/2 ring mark on the piston sure looks like it. When a piston cooling jet fails it usually scores the cyl wall pretty good if not caught in time, so check for scoring. If you overspeed the engine with stock valve springs you can do damage like this.


Good luck,

Tim

Like he said, running to high a rpm.

Looks like the valve seat on the cylinder in question is shot. You don't see the missing chunk?

Yep, look at the valve in the 3 o'clock position in the photo, on the lower right hand side it sure looks like part of the seat is gone.

What's the seat??


I think I've touched the 150 km/h maybe the 160/165km/h during overtaking another car.

So that would be somewhere at 2800/2900 rpm. could that be to high?

I agree, looks like a chunk missing starting at roughly 3 o'clock and ending at about 5 o'clock position.

just went thru this w/ mine... high engine temp(seen too late) stuck a valve, beat up the piston.

Yep the valve IMHO... Valve at the 3:00 position in the first valve photo.... Look close at the 4:00-5:00 position of that valve.. note the metal where the valve is supposed to seal up against is missing (the seat) The lowered compression would result in the mess in the cylinder and top of the piston. Cause... Valve Guide sticking weak spring...

I would look there first.

Also check wrist pin for play.

Sorry to hear about your misfortune. Having the Six Gun will not help you warrantee claim.

Can someone mark the position you mean on the pics?
Becuase I don't understand/see what you mean.

I cirlced the area in red where it appears part of the valve seat is missing.

That is the exact spot I was talking about but on second look while zoomed in I'm not sure. If you zoom the pic way in it looks like maybe carbon is built up everywhere but where you circled.Making it look like part of the seat is missing when really it's just a clean spot. I really can't be sure though. I'm wondering if the spot just above the circle is really the problem because the carbon build up is the worse there indicating a possible leak?

Yes there isn't missing a part of the seat that is carbon. I want that to tell you but I didn't know the right word. But it's carbon

I would still remove the valves from that cylinder and inspect them as well as the springs and retainers. I bet the valve that sits above the damage on top of the piston has a problem you can not see in these pictures. Under the head of the valve there is a "seat" that the valve seal against. These seats are pressed into the head, and on these engines are know to fall down and hold a valve partially open causing it to contact the piston. Keep searching.

I also still suspect the injector for that cylinder unless it has been tested on a bosch test stand for proper operation.

Looks like the piston was overheated from fuel and started to deteriorate.

you have pyro gauges?

if yes how high was it?if not to high pyro temp?

to much fuel on this piston? if banks six gun the problem?

chris

Take the valves out of the head. The seat could have just reseated and is moving in/out of the head when the valve opens/closes. It probably just hung up and hit the piston.

How high of temps had you seen on your guages?

That area you circled just looks like a place where the carbon build up fell out.

Mind you the carbon build up is combined with aluminum particles.

That injector was over fueling, you can see from the pictures looking at the top of the piston where you have the carbon lines running from the center outwards. You have four definate lines and one missing.
This tells me that your injector is not spraying properly, one hole is clogged and the others are over spraying.

Have the injectors bench tested especially the one for that cylinder. If you need a recommendation as to who to send them to I can PM you one. or find a local Cummins shop or diesel injection shop locally.

I agree about the valve looking like carbon fell off.

The EGT's where somewhere around 1100/1150.

I will give al this info to my neightbour.

Does anyone know what the price is for an new block? Because that's maybe cheaper then getting this one repeared.

That cylinder does not look to far gone from the pictures. How deep are the scores in it? I don't believe a new block will be less than fixing one hole. Keep us updated.

We are gonna take the motor out and then let them give a price what it would cost.

My neightbour say's they need to drill and put can's in there.
I don't know if this are the right word's but this is how we say it in dutch.

Cummins does have a salvage sleeve kit made for the 5.9. I would pull the suspect piston only and inspect that one hole. If it is not all scored up then mic the cyl, if it is still good then hone clean it and put a new piston in it. It can be done in with the motor in the truck. I would most definitely send the head out for a complete disassembly and overhaul.



Tim