bobinyelm

Just curious-

I am looking at a cherry '03 6spd 3500 Dually w/ 109,000mi that was never a "work truck," but which has a lot of blow-by.

The truck is SO clean that I am wondering how hard it would be to pull the head, the pan, and pop the pistons up and out, lightly hone the cylinders, and replace the pistons rings w/ new ones, then reassemble the top end.

If I can get the truck cheaply enough, it might be worth it, because I've never seen such a clean, well-equipped low mileage truck I could afford.

I've done this with the block still in the vehicle on lots of gasoline powered vehicles with good success (I've had auto repair shops at times), but have no experience with diesels in general, or Cummins in particular. Perhaps given the high compression nature of diesels makes this FAR more critical.

Anyone have experience either doing it themselves, or having it done w/ regard to cost and results?

Thanks,
Bob

rich

that sure is low miles to have bad enough blow by to need to be re ringed. it can be done in frame but getting to the #5 and #6 is going to be tough from the top

bobinyelm

After a LOT of searching (web searches), it seems it's rare, but not unheard of at around 100k for some trucks, though it does baffle me.

Any OTHER reason to be spewing a cloud of blow-by smoke from the crankcase breather at even idle?

NO exhaust smoke that I can see.

I hate to "Pass" on this vehicle (It is super clean w/ a leather interior, premium sound, silky 6spd, and the right white), but I don't want to put myself in quicksand, either.

If I could "buy-it-right" and have it tight w/ new rings at a decent price I'd be happy. That way, I'd know what I had when I was done (since I'd see the bores, the crank, etc.)

But YES, the back cylinders would be tough, though w/ the head removed, there may be room to run a hone up, down, and get the piston and rod out/and back in again.

I'd love to find someone who's done it.

Bob

krh

I dont know if you can get the pan out with the engine still in its mounts. I havent had to on my 05 yet so i cant say for sure, but i dont think that pan will come out without lifting the engine at least an inch or two. If it was me id be tempted to pluck the engine right out for the rebuild. It shouldnt be that much more work and then its easier to work on and you can probably keep everything cleaner when its going back together. Also could it be a bad valve, seat or guide letting pressure by. Of course having done motors before youll know what to look for on the head anyway. You should let us know what you do if you do buy it. Id like to know how the motor work goes cause mine may be coming due soon.

Purplezr2

You can get the oil pan off on a 24v just need to lift the motor alittle.

rich

you have to lift the motorup but its about 3 inches did it on the 03. the only thing is you mit have 8 inches of room from the top of the block to the firewall. if you can do it let me know i have an 07 that i need to do it to and i really dont want to pull the motor

bobinyelm

On gassers, at least, a burned valve will lose compression, but it won't pressurize the crankcase.
Theoretically, a badly worn guide "could", but at idle the intake and exhaust are both pretty close to atmospheric pressure, so no pressure would go into the crankcase.

At full turbo boost, perhaps a bad intake guide could let some pressure in, though.

What I have to decide is if there is a price at which the truck would represent a "good deal" even if the ring job cost me more than I guessed at the outcome. There IS such a "number," but I doubt the seller would sell it for that much!

Bob
P.S. Thanks for the info on dropping the pan on the 5.9.

bobinyelm

8" "should" be enough to snake the piston and connecting rod out (depends on the length of the rod, which one can look up anyway), and is plenty of room to snake a flex-shaft hone down in there, especially since the idea is hopefully to just break any glaze on the cylinder walls so the new rings will seat.

Obviously, if you see gouges from a broken ring, you're going to have to pull the block to go oversize or sleeve it.

Bob

rich

if its got that much blow bye i'm laying odds its got a gouge or broken ring

bobinyelm

Probably right. There is a reason such an otherwise perfect truck is being sold at a price I can actually afford!

Bob

Purplezr2

Looks like it can be done in frame, reringed that is


https://www.dieseltruckresource.com/...s-t253391.html

Brian Lent

Yeah it is a pita dirty job getting it apart but after you clean it all up it's not too bad putting it back together. Honing is pretty simple except for catching the oilers on the bottom. The hardest wrenching is getting the suction tube off before the pan will slide out. Had 600 in rings, gaskets, connector tubes, and drain tube. 600 in the valves, guides, etc. and 500 in head gasket and arp's overnighted from brown's. And I now know my engine better then most! Priceless