We're trying to get Passion Flower ('85 300TD...mucho miles) back on the road and not having a good go of it.

Symptoms:

Engine fires off easily but has a horribly rough idle and won't idle reliably at all until it warms up some.
Even after warm, engine idles rough and responds poorly to throttle.
Plenty of bluish-white smoke. Smoke doesn't smell strongly of diesel or burning oil.

What's been done:

• Valves adjusted - none were more than .002" off despite going at least 30k w/o an adjustment
  
• Ran straight Stanadyne cleaner through fuel system - no change
  
• Injectors pulled and tested - OK
  
• Priming pump was leaking badly - replaced with used but non-leaking pump. Interestingly enough, the thing fired up and ran fairly smoothly for at least 5 minutes. After that, it went back to smoking and rough idle.
  
• Checked valve timing and chain elongation (and here's where it gets weird weird) - going by the rough timing method (aligning the assembly mark on the cam and the pointer on the crank) nothing is even close to lining up!!! When the cam mark is aligned, the crank mark is at least 30° to 60° off. I get pretty much the same results when using the dial indicator and 2mm of lift. Also, the slack side of the timing chain is exactly that - slack. I mean you can grab it and move the chain. I'm pretty sure that isn't right.

What the hell is going on with this thing? It seems likely that it's jumped time but it sure doesn't seem like the timing could be this far off and 1) still run or 2) not have bashed it's valves into oblivion. Any other ideas?

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Never a dull moment at Berry Hill Farm.

There ain't no way your chain should be slack. Start there. I would check chain tensioner. And I wouldn't turn it over any more until you figure out why the chain is slack. You may not have jammed a piston into a valve yet, but it sure is a threat for the future if you don't figure that thing out. I hope others chime in on getting the timing back to spec. With the tensioner out, I think you can inch the chain over the cam sprocket to get the timing marks to line up on the cam tower and the crank.

But will his IP be out of time? Is there a risk that the IP gear has jumped a tooth?

Agreed. Chain tensioner and slide rails. Slide rails being plastic are most likely to fail and could cause slack.

I've never timed a 617 though I reckon it's not too far off a 603. If there's doubt about where the engine is, then an A-B IP timing light is critical for piece of mind. As long as you have one of those, retiming is pretty straight forward (line up cam and crank...line up IP).

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1982 300TD 210K miles ("The Replacement" aka "The Anvil") - SOLD
1979 300SD 245K miles (never ending project)
2007 Pinarello F3:13
1995 Ducati 916 (SOLD, sniff)
1999 Ducati 900SSie (SOLD)

I agree also as to what is stated. But I would check to see if your woodruff key is still there on the crank. Being 60 degrees off is a lot. And personally I would spend the extra time to make sure the balancer is in a correct position.

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1983 123.133 California
- GreaseCar Veg System

Randy, can you kindly provide some history of this engine?

What's been done regarding the chain and the camshaft?

A proper description, from the beginning, would be helpful.

Sure

Nothing so far.

You asked for it...

Background:
Car purchased in Austin, Fall 2003 w/bad transmisson (failed because of coolant contaminated tranny fluid), mileage unknown-odometer not working. Replaced transmission, bad trailing arm bushings and pulled routine maintenance (oil, filter changes and valve adjustment) on engine. Car then traveled to Long Island and lived there about 1 1/2 year before being driven back across US to Texas then to Oregon and on to Skagway, AK. Fairly regular routine maintenance...oil changes etc. and no significant problems during this time other than a bad glow plug that was replaced and replacing a road hazard damaged oil pan. But probably no valve adjustments done during this time either. Started and ran OK in cold-ass Long Island winter and on multiple winter trips to upstate New York.

Vehicle spent summer '05 in Skagway. It was about at this point I started receiving reports of it 'taking a long time to warm up.' Driven intermittently in summer of '05. Fall '05 the car was moved to the lower 48 and parked in Oregon. It wasn't supposed to be in use by anyone at this time but managed to acquire a significant dent in the LR fender, under the window - maintenance history uncertain during this time.

Early winter '05, vehicle driven from Oregon to San Diego and then to Austin. At this point I was able to witness the running issues associated with the poor running: periodic blue smoke, periodic black smoke, poor throttle response, poor idle, reduced power. I bought the car back from Seth in Jan '06 and drove it to Moody's for storage (never hurts to have a wagon head in stock, right?).

Jan '07 vehicle restarted (with all the symptoms stated above) and driven back to Austin from Moody's farm.

All things mentioned in post #1 done in Jan-Feb '07...

Additionally, the primary and spin-on fuel filters were replaced when this troubleshooting process started. And, the aircleaner was removed to determine if a blockage was causing poor running; removal had no effect.

I cannot think of any other relevant facts.

__________________
Never a dull moment at Berry Hill Farm.

At least it will run so your valves may be okay still. I would not even spin this engine over with the starter right now until I figured what is going on. It does sound strange overall. Reach down and see if your bottom pulley is tight. I would check the cam sprocket to make sure the key is still there as well. Then pull the balancer and check the bottom sprocket out and it's key. It might have just jumped the chain but you cannot just assume that. Did you notice any clang type noise when shutting down or starting up? Do not try to see if it is there now. Just try to remember if you heard it before. Broken cranks make that noise usually. Highly unlikely for the crank to have broken though. You may have heard a loose chain slap as well instead. You hopefully will save the day. Basically it just sounds like a jumped chain at this time. I still would check everything out. Just make sure not to push your luck at this point.

I would also start with the timing chain issue, it's not safe to run with a slack chain anyway. When my timing chain jumped one (I think) tooth (broken vacuum pump), it did run without valve interference, but it ran very poorly (low power, lots of black smoke). I suppose it's also possible that the IP timing is off by a different amount than the cam timing if the chain is slack.

Thanks for the history. What's a bit baffling is how the vehicle deteriorated to this condition. Presumably, it was running "properly" when purchased and slowly deteriorated to the current state of affairs. But, timing that is 30 degrees late doesn't occur with an elongated chain. It's almost as though the camshaft sprocket is slowly rotating on the camshaft.

However, you've confirmed the fact that the timing is improper via the valve lift method. If the camshaft is one tooth off, the timing is 20 degrees displaced at the crankshaft. Two teeth would be 40 degrees. The engine can definitely run with a displacement of one tooth..........two teeth would be news to me.........but, it cannot be ruled out.

I think you've got to begin with setting it back to proper timing. But, the reason for the large change must be investigated and my vote is the camshaft sprocket for a first guess.

The slack in the chain on the tensioner side does not affect the camshaft timing results. It does appear that the ratcheting mechanism and/or the spring in the tensioner has failed and you've only got tension when the oil pressure rises. It's a relatively easy fix.

I'm curious to see what might have caused the cam timing shift.............

Edited: One caveat on all of the above:

It's assumed that the balancer is intact and has not rotated on the crankshaft and the valve timing readings are accurate. This may be a false assumption. It wouldn't be the first time that a balancer sheared it's bolts or pins and rotated. Therefore, prior to making the assumption that your cam timing readings are positively offset by 30-60 degrees, it's probably a good idea to verify that the timing marks on the balancer are correct. The fastest way is to verify that #1 is actually at TDC when the marks are at 0 degrees. There's probably a decent method of doing this by releasing one of the valves and letting it sit on top of the piston...........Greg may have a better idea on this.

FWIW-We haven't run the engine since discovering the loose chain.

After listing all this out, I'm thinking that we're seeing the results of a combination of things:
1) Failed chain tensioner or associated parts not applying correct tension to timing chain.

2) Loose timing chain causing erratic valve timing at idle (engine did smooth out above 1000RPM) - cam timing possibly off one tooth.

3) Bad/failed harmonic balancer - indexing dowels missing/sheared, balancer has rotated and is giving incorrect degree reading (actually no reading is possible) at the pointer.

Comments?

__________________
Never a dull moment at Berry Hill Farm.

Take apart whatever you have to take apart to make SURE that all timing chain rails are intact. That done, get crank, cam and IP in proper relationship. Have you had the IP off the engine?

If it were mine, I would ensure or get ALL rails in good shape, ensure tensioner integrity, time crank and cam, then do drip method timing on IP but only after ENSURING crank/cam timing.

Can this wait three weeks? If so, we can put together an assault team and take care of it March Third.

Good luck,

We've never had the IP off.

Understood on the tensioner integrity and everything else. An assault team sounds like a good idea but the car is in Austin and the GTG is in Milano.

Thanks for chiming in Larry!!!

__________________
Never a dull moment at Berry Hill Farm.

SInce the pump has not been out then I would say that with the tensioner and rails all in good shape, it is a simple matter of putting the crankshaft in the proper position at 20 BTDC or whatever the spec is for that particular engine, align the cam mark and then see if the IP can be moved enough for proper drip.

That said, the slack in the chain is your biggest indication. If you have corrected this portion of the problem, it is time to get the pump to drip, but only while the cam and crankshaft are in their proper positions with chain taught. If you get cam and crank in position with a tight chain and you CANNOT get a drip, then you will have to slacken the chain and get the IP sprocket properly positioned with relation to the cam/crank. You may even have to pull the IP to observe the position of the notch in the splines.

It sounds very much like there may be a timing problem between cam and crank. This means PROCEED WITH CAUTION! Remember, this is a diesel engine with nowhere for the valves to go in the case of incorrect time. If the cam is retarded a notch you won't have piston/valve contact, but if it is advanced, you will.

At this point I would not worry about fancy timing methods. I would just get the cam/crank in position with a taught chain, then see where the IP timing falls.

I know that I have been triple redundant with this post, but it is important for the health of the engine.

Best of luck,

Thanks again Larry! I truly appreciate all the input.

It's not a totally "done deal" but we're thinking about decomissioning this vehicle and relegating her to parts car status. Thing One isn't willing to put in the money needed to repair the engine and the body is in really rough shape so, I'll probably store her out at the farm and someday pull the engine for rebuilding and eventual intallation in my wagon when her engine gets tired.

__________________
Never a dull moment at Berry Hill Farm.