M7040 Smoking with Fuel in Oil - help

[dmann33]

Your thinking it's like an old distributor on a car, it's not!
Removing or reinstalling the lines would have Zero effect on the timing.

My understanding it would as the delivery valve is adjusted by rotating the base nut/fitting that the injector line screws on to. This nut/fitting has a tendency to rotate when tightening or loosening the injector line if you don't use a second wrench to keep it stationary. I hope that make sense.

I'll update soon on the outcome of all this.

 

[North Idaho Wolfman]

Ok I'm going to eat a little crow, the injector pump is somewhat like a distributor and you do turn it to set the exact timing, older models use shims.

The line fittings do not adjust the timing they are just tight, you will not throw the timing off by loosening or tightening those fittings, the adjustment is done by moving the whole injector pump housing with separate lock down bolts.

The manual spells it right out how to adjust the timing on page 145.
If you don't have the service manual PM me an Email address and I'll send you a copy of the service manual.

 

[ShaunRH]

Is it a mechanical pump or ECM based? It sounds mechanical.

Now, it's possible something caused the injector to stay open and the cylinder put in enough fluid to slam the piston and rings (intake valve not opening would eventually fill a piston too). This could've damaged the rings, the journals, the bearings or anything in the cylinder. Now it's not happy. That #475 when the others are running #500+ would bother me, why is that cylinder down so far?

I'd tell them to repair the entire cylinder and let them know it's on their dime. The compression reduction, by comparison, should bother them more than it is. You may have a defect in the cylinder, which I would buy more than the timing.

Old School logic:
If #1 timing is off, so would all the others and it wouldn't run at all, or sound like it wants to die. That first cylinder, TDC is critical to the timing point. Everything else follows. On mechanical pumps, that's where all the marks line up, #1 TDC. If yours is electrically based then I guess it doesn't matter, but that cam will likely still be timed to #1 TDC.

If you look at this from the triangle of fire perspective: Fuel * Air * Heat . You seem to have ruled out two of them, what about air? Is the valve working properly? You mentioned something about it, but if it's not getting enough air, that will also be a problem...

This is all mechanics 201, not basic but intermediate. I'd tell Kubota to find and fix it and let them know that cylinder is their problem until the engine dies of old age so they'd better fix it right. I don't think you have a lemon, per se, but you certainly might have had a bit of bad luck and it caused a problem... it happens.

 

[dmann33]

To wrap this up and as a final update, it was written up as a dusted engine due to failure (leakage) of an induction hose.

It took 60 days to diagnose and get that claim approved. After another 14 days, the dealer rec'd the wrong engine. When they went to order a 2nd time, the engine was on back order for 7 weeks! (meaning it would be over 120 days without my new tractor). I pushed a little at Kubota in Atlanta and they found an engine in Canada. It arrived at the dealer right at the 90 day mark and of all things the mechanic just left for vacation! Another 10-14 days and I finally had my tractor back in the last 1/2 of July.

Frankly, I still find it hard to imagine the engine was dusted beyond repair since the compression was still within spec. I further don't understand why that front cylinder would not be firing IF the compression was still within spec. It just doesn't add up to me. Although, after waiting 3.5 months, I wasn't going to complain about a new engine...I just needed my tractor already.

So, the mystery is still there. They also showed me the intake on the engine (where the hose from the turbo delivers air to the engine) and there was chalky black residue there. They told me that was not normal and that this was the evidence of "dusting", but since the turbo also pulls air from the exhaust, wouldn't that be expected? Does anyone with experience know what kind of residue (if any) you would expect to find at that spot?

Many thanks!

 

[kuboman]

Dusting an engine will not wear just one cylinder, they will all wear equally. And yes the black residue is from the EGR. Makes no sense to me to be injecting abrasive carbon particles into an engine. But that's the great EPA that's foisted this garbage on the rest of the world.

 

[North Idaho Wolfman]

but since the turbo also pulls air from the exhaust.

Not really, The exhaust gases spin a turbine that shaft connected to a second separate turbine that forces air into the engine. The 2 never exchange air unless, the turbo is bad. I hope they changed the turbo out too or you could be in for the same problem shortly.

 

[CaveCreekRay]

Toyota tried that crap with me on a late warranty repair for valve guides. Motor started smoking and I got it in during the last 60 days of the drive train warranty. My daughter was on top of all her oil changes (every 3K).

When the dealer told me the same thing, "You don't have any proof of oil changes! If we get in there and the head is all gunked up from too long an interval on the oil changes, you are gonna pay for the head overhaul." I told them it would be clean when they cracked the head off.

I called back later and the service writer laughed. They pulled that head and found it immaculately spotless throughout the head. The Toyota regional guy drove out there just to slam me and left in a huff when the problem was found to clearly be Toyota's. The mechanic said they had never seen a head that clean.

You don't need paper to prove oil intervals. The proof is in the engine.