Engine/Transmission (1998.5 - 2002) Are these "throw-away" blocks

[jtisdale]

A friend of mine, and 2nd CTD owner has been trying to convince me that our engine blocks are throw-aways because they have no cam bearings. Just a steel cam running in a cast block. Is this true??



I cant hardly beleive these thing dont have cam bearings...

 

[lmills]

I am not sure, but it sounds like he is wrong. A lot of people rebuild these when they go.

 

[jwilliams3]

Yeah 1,000,000 mile throw away blocks!



There is one Cam Bushing (bearing) that is installed in your block

located at the front of the engine next to the gear train.



On 03 model year Cummins engines there is one at the rear of the block as well as the front.



The Cam rides without bearings in its journals inside the engine block. The Engine block is machined to perfect tolerances. This is why this can be done without failure.



--Justin

 

[340Mark]

Yes only one cam bearing at the front, but thats where the load from the gears is. The cam rides on a oil film thus the religious oil change practices. The valve spring pressure is not very high on the lifters compared to a high revving gasser. I'm just starting a rebuild caused by broken piston rings, so I'm learning a lot.

 

[Big_Daddy_T]

They are also not wet sleeved like the larger medium dutys. Replacable liners make it much easier to rebuild. Its parent bored like its cousins the 7. 3 and 6. 0.

 

[Big_Daddy_T]

Ohh brainfart. Cummins claims the 5. 9 is rebuildable 6 times. So if you rebuild it every 300k. That would mean a hypothetical 1. 8 million miles. On a throw away.

 

[tgbol]

Cummins supplies oversize bushings for the cam journals if you align bore the block. The also supply sleeves to repair the cylinders.