meltdown -- common rail style

Joesixpack said:
Comparing a few seconds on a dyno, is nothing like 25-30 on a pulling sled.
I doubt your egt guage can even stabilize in that time.

I guarantee you, there is no way these engines can hold 1000 for that long, without excess fuel cooling, or water.

That coating on Bean's pistons sure held up great.
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How is it that Cummins says towing for extended periods at 1000 plus is allowable? I have heard this on these forums before
 
shiftycapone said:
How is it that Cummins says towing for extended periods at 1000 plus is allowable? I have heard this on these forums before
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LOL um...yeah thats HP there.....take a stock engine (325), You could tow at 1400 all day long, all year long, for the life of the engine.


Tweek that same engine just a little....say the 1000HP mark, ...now without proper cooling, were talking life time in seconds.
 
Joesixpack said:
Comparing a few seconds on a dyno, is nothing like 25-30 on a pulling sled.
I doubt your egt guage can even stabilize in that time.

I guarantee you, there is no way these engines can hold 1000 for that long, without excess fuel cooling, or water.

That coating on Bean's pistons sure held up great.
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This was on the track.... not just the dyno. :poke:

Here are a couple of videos to get the idea of how clean it was

Truck Vids :: CIMG0432.flv video by chrleb1 - Photobucket
Truck Vids :: CIMG0430.flv video by chrleb1 - Photobucket
 
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2007 5.9 said:
So with my semi-retarded math I think that at 4K the injector fires 50 times per second with all three injection events ocourring.

Heres the math...correct if wrong...

4000\60=66.67 rps. 66.67\4(numbers of strokes per cycle)=16.66 revolutions per power stroke. 16.66*3 (injection events)=50 injector fires per second.

My math might be off....
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Your math is incorrect. You need to only divide by two instead of four, yes its four cycles but still 720* per combustion event (not 16.66 revolutions). If there remained three events per power stroke, it would be 100IE/S. I don't belive there are three though in the higher rpm. What we could be calculating here is Duty cycle only we don't know the durration or number of pulses of each injection event.
 
Does anyone have any pics of an 03-04 piston that they can post up so we can get a better idea of the re-entrant and non re-entrant designs?
 
I'd use the QSB 480 pistons and nozzles, that was my choice before I found out there was a set of monotherms left.

Maybe coat them, why not, but I'm not sold on it...again I'd rather see water injection if your pulling and I imagine your class lets you.

Well for that matter the 03-04 electronics are better as well but I imagine a PITA to make work maybe not so bad without an auto tranny.

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Back when I bought my CR they weren't out long and nobody knew much about them. If I knew what I now know I wouldn't have bought one in the first place. I hope I don't have a melt down but if I do I'm not sure I'd rebuild it and if I did it wouldn't happen to me again. I would let some one else have it and I would buy a 12V. I just don't like the way a CR runs.
Billy
 
joelc79 said:
So j.p., what are your plans? bigger injectors and coated pistons?
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Unless someone can convince me otherwise, It's going back stock. CR engines have a lot of potential, but we haven't got them figured out enough for me to feel confident in another build. Even if we could make them live in extreme conditions, we aren't making any power above 3200 rpm. Add upcoming CA smog regs to the picture and all of a sudden 12 valves make a lot of sense.

I have a 92 regular cab 4x4 ready to go.


-jp
 
jlibert said:
Unless someone can convince me otherwise, It's going back stock. CR engines have a lot of potential, but we haven't got them figured out enough for me to feel confident in another build. Even if we could make them live in extreme conditions, we aren't making any power above 3200 rpm. Add upcoming CA smog regs to the picture and all of a sudden 12 valves make a lot of sense.

I have a 92 regular cab 4x4 ready to go.


-jp
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P pump it .
 
JOESHTRDDSL said:
EGT probe or gauge could be wrong, always a possability. If the gauge is showing the wrong readings then why do two of the pistons look like new? Not trying to argue just trying to help figure out what went wrong. You would thing 4 pistons melted that bad it would have at least damage the other two in SOME way. I am no expert but I am at a loss. I am starting to think no one is an expert on these CR's

Joe
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Whats he runnin for CP3(s). Same thing happened to mine with a stock CP3 only burned 3 pistons, Was draining the rail before the last 3 pistons burnt up. Trying to figure out why these melt this way is *bdh*. Very sorry to hear that happen. What size of injector?
 
doug60 said:
P pump it .
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Already have a 95 12v with a 47rh.

cummins04.5 said:
Whats he runnin for CP3(s). Same thing happened to mine with a stock CP3 only burned 3 pistons, Was draining the rail before the last 3 pistons burnt up. Trying to figure out why these melt this way is *bdh*. Very sorry to hear that happen. What size of injector?
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Dual stock pumps, Flux 4 (about 200hp injector)
 
jlibert said:
Unless someone can convince me otherwise, It's going back stock. CR engines have a lot of potential, but we haven't got them figured out enough for me to feel confident in another build. Even if we could make them live in extreme conditions, we aren't making any power above 3200 rpm. Add upcoming CA smog regs to the picture and all of a sudden 12 valves make a lot of sense.

I have a 92 regular cab 4x4 ready to go.


-jp
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I knew you were wise beyond your years the first time I met you.:rockwoot:

RonA
 
I don't know much about CR other than what I read here or have learned from talking to others but i've been told the camshaft in these motors in stock form doesn't flow alot of air compared to other cams. Are you guys burning pistons all on aftermarket cams? I would guess so given the power levels some of you are making!
 
I have a bone stock motor... i just have programming, turbo, fass duall cp3 stuff like that.. i just got my injectors back they all checked out fine???? im lost now...
 
RonA said:
I knew you were wise beyond your years the first time I met you.:rockwoot:

RonA
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I'm going to have to learn a lot about 12 valves in a hurry -- hope you don't mind a lot of questions. :Cheer:

outlaw99 said:
I have a bone stock motor... i just have programming, turbo, fass duall cp3 stuff like that.. i just got my injectors back they all checked out fine???? im lost now...
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Yeah, that sucks.

If I had it to do over again......
even SW with least timing
3500 max rpm
maybe some water

This time around you might as well coat the pistons. Talk to Erick at Brown's Diesel about switching to the 555 pistons -- he'll give you the scoop.

-jp
 
No way, That's Awsome! It' funny, I just bought a 12 valve with the thought of returning my CR back to stock, or close to stock. Bring your rig up to Ponci's event, I'd like to line up next to you. My 12v is a total grandpa rig too.
 
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