CM2250 low power poor mileage

[Rockinbexpress]

Snail express I just made a setup to put on the pressure side of the fuel pump. I'll post what I find

[Rockinbexpress]

Update I pulled the head and found exhaust valves on 1-4 warped/bent and discolored from heat. Head cracked between exhaust valves on 1-3 and cracked between intake and exhaust on 4 and 5. So.... Bad deletes are expensive AF!!!!

[Truckdriven]

(10-25-2022 )Rawze Wrote:  

(10-25-2022 )Rockinbexpress Wrote:  Rawze I wouldn't think carbon packing would be an issue as this motor was demandated out of the box 3 years ago. Would you?

...

(10-25-2022 )Rockinbexpress Wrote:  I just got the oil sample back and everything is good. No carbon, fuel or water.

That does not mean anything.

Only turning the engine by hand and knowing how tight one usually is to turn will reveal how much resistance the engine has.

So is it possible to have a carbon packing problem and not have any symptoms, no oil consumption, only poor fuel economy?? Is there any way to check without pulling piston in that case? I have a CM2250 with lower than normal fuel economy as well.....

[Rawze]

(12-03-2022 )Truckdriven Wrote:  ...
So is it possible to have a carbon packing problem and not have any symptoms, no oil consumption, only poor fuel economy?? Is there any way to check without pulling piston in that case? I have a CM2250 with lower than normal fuel economy as well.....

seen it plenty... if its hard to turn by hand, it will have fuel mileage issues and when it gets bad enough.. hard starts as well.

-= Saw one in Haggais shop that was so hard to turn (via a wrench) it was going to snap the adapter off the face of the air compressor before it would budge. -= guy was there only for an overhead adjustment.

I happened to be there that day and pulled on the wrench to turn it over myself ... and it was the worst one to turn by hand that I had seen yet.

It did not have any notable issues other that complaints of hard starts. It ended up with an inframe before it left it was so bad.

When the pistons came out, the rings were pushed so far away from the grooves due to the carbon buildup behind them, that they were sharp as razor-blades on their outer edges + extremely thin.. about to snap, from rubbing the liner walls so hard all the time due to the carbon packing that had gotten behind them. -= This guy is lucky he did not end up with a piston thru the block, it was so bad.

This was all caused by running the engine at low rpm's its whole life, plus completely neglecting the EGR, after-treatment, and other systems, making the engine produce tons of extra carbon and soot all the time while going down the roads. You could also tell that the engine block as a whole and the oil system was very soot packed too, from all the neglect (considered abuse).

[Rockinbexpress]

I am at my wits end with this engine. Can anyone recommend a shop in central Oklahoma that knows these engines and isn't a hack/parts changer. I'm still having the surging problem and lack of power and mileage. I'm going to heat the turbo up tomorrow and check vgt function again but if that's good I'll need a shop

[Rawze]

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