Losing Power
 

I own a 2000 Pete dump truck with a 3126B Cat in it. It has 490000 miles on it. I recently had all the injectors replaced due to bad o-rings (oil getting in fuel) I thought that this would also solve my problem of decreasing power. It still has terrible pulling power. That engine is rated at 300 horses. It feels like I'm only getting about 250 or so. The truck was fully serviced at a reliable cat shop. I also had them to be sure that it was turned up to the max to get the maximum performance out of it. The only other thing that's crossed my mind is my cooling system. I know that it needs to be serviced and cleaned out. It does have lots of trash and buildup due to the type of work I do with it but could this be causing it to be weak in power? It does have a tendency to run hotter than it should. Suggestions?

Did you check the turbo, air filters, etc? I don't think coolant would have much to do with it, running hot is running hot, all that will do is tear up the engine quick :)

Have them check your Intercooler if that has a LEAK in it you will be running hot for one reason your engine is losing POWER and the Computer is dumping fuel into it to try to get the power back up and causing a bigger issue.

Actually, if the intercooler is leaking, it'll be losing boost pressure, and the manifold pressure sensor will see less manifold pressure, causing the ECM (computer) to tell the injectors to deliver less fuel, causing low power.

Cranky I have seen it BOTH ways on CATS. It would also EXPLAIN the high heat he is getting. I had one that the freaking thing was losing 3 lbs of Pressure most of the MAP sensors do not cut the fuel delivery til 5 lbs of loss since then the ECM thinks the Turbo is failing. Someplace he is loosing Boost pressure and that will explain his problems. Also with all the trash in his Intercooler he could have a hole a very slight one and it could be partily plugged up not so it could be leaking just not whistling as it loses the boost. Air is like water under pressure it will follow the path of least resistance lets see here get rtammed into a clylinder or flow out a hole which would you do.

i would get your intercooler pressure checked and check all ur air intake pipes u had a hole rubed through my intake from the valve cover and my intercooler had a pin hole it makes my 525 cummins run like 450 and they think my motor is dusted but im going to run it till it goes and ill just get a recon dust is your worst ememy for you motor expecially in your kind of work also get your fuel lines cleaned maybe i got mine cleaned out i think i gained 30 horse by getting all the junk outta the tank and lines

He said 3126 B! B folks. No computer. Nevertheless, if the charge air cooler is leaking, the aneroid won't get the pressure to pour the fuel to the engine. It'd definately cause heat and lack of power though.

The 3126B is fully electronic. It has a HEUI fuel system, hydraulically actuated injectors (like the IH built Ford Powerstroke Diesel); they definitely need a computer.

The 3116 CAT was mechanical, and later partial elect fuel control.

The 3406B is PLN mechanical injection.

I'm thinking most all 2000 road trucks have electronic managed fuel, no?

If your intake leak is on the charged side of the intake system, the pressure will usually keep the contaminants out of the engine.

If your leak is between the turbo inlet and your air filter housing, you will dust your engine faster than a "popular" cone filter dusts a ricer engine.

Ahhh yes. My mistake...Bob H is correct.