papaindigo wrote: It's certainly possible that it dropped a piston into a valve as that's happened at least once but on the scale of things that's relatively unlikely. Here is what I can tell you based on the limited information at hand.
1. loss of power and smoke WITHOUT somewhat obvious engine noise could be as simple as blown intercooler hoses. So ? what noises did you hear? Was engine still running?
2. unless the mechanice disassembled the front end of the engine (remove fan shroud, remove fan, remove various "things", remove timing belt cover) then A) he did not look at the timing belt rather he looked at the serpentine belt and B) he has no clue about this engine.
3. there are no timing "marks" to be checked. Rather there are intake and exhaust cam pins and a flywheel pin that can be used to check and set engine timing during a timing belt install or after engine tear down. In theory they can be used to see if timing is off but only per FSM
4. lack of compression when air pressure is feed into cylinder X tells you abolutely nothing except that air is going out of the cylinder which can be for a variety of bad reasons or a simple reason such as that piston's valves are open or partially open as it's sitting on the normal intake or exhaust stroke. Sorry for the rather obvious comment but when one is as worried as you are the obvious may slip by.
5. if in fact you had bad engine noises when you had loss of power and smoke it's certainly possible, at 119k, that your timing belt slipped or broke (if former engine would run with bad noises; if latter engine won't run). Yes this, like any diesel, is an interferance engine BUT in the event of timing failure the valve rockers are designed to collapse and save the valves and pistons; has happened to several. Fix is to pull head and install all new rockers and lifters which runs ca. $1000 parts and labor.
Where are you? As noted above I have my doubts that the referenced mechanic has a clue about this engine. Not a good start if he is willing to listen to forum suggestions and read the FSM sections. Depending on your location there may be forum help relatively close by.
Thanks papaindigo, I'll try to break down what I know and I'll try to talk to the shop again later today to clarify what he has checked and how deep he has gone.
1. Definitely lots of engine noise. Engine ran terribly rough. Sounded like mechanical interference to my untrained ear. My first fear was that the TB had skipped and thrown the whole thing out of timing. When I got off the road I shut it down and did an initial once-over to see if there was anything obvious - fluids, belts hoses... Nothing jumped out. I tried to start it again and it sounded so bad that I just shut it down and made the call for a tow. Bad = extremely rough/loud, barely staying at idle, spastic RPM's
2. I'll confirm that he did not check the serp belt, but I'm pretty sure he didn't. On the side of the road I actually found that it's really easy to take a "peak" at the timing belt by just removing 3 screws at the top-front of the block on the black cover plate. You can only see the top 2 gears and about 8 inches of the belt, but I'm sure this is what he used to roughly guess that the belt hadn't been changed when I went in for service a few weeks ago to have it checked out and have the tstat replaced. In this case he may have torn down more of the front end of the engine to do a full check, but I'll have to confirm.
3. Good to know. If it comes into question I'll relay that.
4. Yeah, this is a fair argument. I'd have to clarify what he was actually doing, because it doesn't make sense when you stop to think about it. I do think they did a compression test on each cylinder and they concluded that Cyl #4 had zero compression, but I don't know where they went from there or how they administered the test. They have only had the vehicle for a couple of hours, so these are initial observations and I'm asking for a bit more detail this afternoon, so we'll see what comes of that.
5. I'll definitely mention that this is a reasonable option. His fear was that something fell into the cylinder I think, so scoring would have made a rebuild unreasonable.
I'm in Fort Collins, Colorado. I know there are other CRD's in town, so I'd be happy to hear input if there's a location in town that really knows these engines. I can tell from a brief experience that my local dealer does NOT fall into that category. They are the ones that tried to tell me that my stuck open tstat was an electrical issue and they would need to monitor it for a few days to figure it out. (haven't been back) I would be open to trailering it to another dealer in the area or certainly a mechanic who knows the engine. I would say that my local guy isn't an expert on this engine, but he's reasonable and knowledgable and covers diesels in general. If I have another lead he won't give me a hard time about taking it to an expert. And he's not necessarily asking for my input from the board, I'm just a troubleshooter and I can't help myself.
All of my info so far from the mech is based on a 20min conversation this morning after he'd had the truck for 2 hrs, so I'll try to get some better details this afternoon.
Thanks again...
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