CUDANUT

Bought a truck in a box so to speak with the block sitting in the bed. The original block had been sitting with the head off (rusty). The pistons were badly seized so they were trash and one rod was missing. Block was not cracked so we bored it .020. One rod was bad and the machine shop gave me one from a 12V engine but they have different casting #'s 3942578 on the old 24V rods and 3901566 on the 12V rods. Will they interchange?? They look the same but I'm sure you guys will know... Also several new parts were in the truck (gaskets, new starter etc...) the head gasket has part#3958645 which is wrong according to my book. The book shows it to fit 03 up?? Did the previous owner get the incorrect head gasket or has it been superceded to the later style?? Since this is a stock build do the head bolts need replaced?? Any other words of wisdom?? I'm not trying to cut corners, just keep the $$$ down if possible....My household is in "recession" with all these high energy prices and college bills...

CUDANUT

Opinions on the condition of the deck... Machine shop thinks its ok since its flat but it does have some minor pitting. Is the pitting enough in your opinion to get it decked?? This will be a stock rebuild and the head has already been done (it was fine with no cracks) Should I get the thicker gasket since the head has been worked and milled??

HOHN

I shallow pass on the mill is a good idea. You want to do everything you can to keep that head sealed, even on a stock-power rebuild.

I'd consider the gasket only if I knew how much the head had been whacked. Assuming a .010 cut, I'd go with a slightly thicker gasket (if a .010 is available), with the intention of preserving the piston bowl/injector spatial relationship.

JH

CUDANUT

Head was cut 0.010, pistons are 0.020 Mahle replacements.

Kennys

Were you able to buy the pistons without going to Cummins and how expensive were they?

CUDANUT

Bought the pistons from a local engine parts wholesaler. They crossed over the original casting #'s on my pistons in Mahle. They look identical and were $484 including the rings. Total machine shop bill was $770 including a head rework with new guides, clean/bore/hone the block, new cam bearing and polish the crank.I need to figure out the head gasket problem since the truck had a different # head gasket still in the package in the back seat. I should end up with about $1600-$1800 in the total rebuild. Not bad considering I bought it at auction for $1800 (99 2500 SLT Ext cab, 5speed) The trans was also rebuilt 5K miles before the engine let go. I have no idea what the original problem was to cause the galled piston on #3. It came from a closed up trade school that was using it in their diesel class as a test bed.

Kennys

Glad to know they are available through Mahle, they made the originals. I have a machine shop and have done several of these blocks and heads. Believe that resurfacing the head doesn't matter on the gasker thickness. It's not like a gas engine with a combustion chamber built in the head. If you deck the block you do have to have a thicker gasket. I have a Cummins shop manual at the shop and will look this up. Do remember that the block can be decked twice but don't remember the amount. The manual does state the amount and tells how to mark the block somewhere with an X for the first cut and two X's for the second cut in case someone tears it down in the future. Haven't done one recently and not for sure on all this but will get the manual and look it up. Will try and do this tonight or tomorrow.

CUDANUT

You are correct on the "X" markings, that is what the factory manual tells you to do when you mill the block. I wasn't too much worried about the head since its a flat head and the only thing milling can do is make the valves slightly closer to the pistons. The main worry was the condition of the deck and should I mill it?? Also I asked the question about the 12V and 24V rods?? And the #'s for the head gaskets??