Blown CRD.

geordi · **Posted:** Sat Oct 03, 2009 2:42 pm

Turbo Tim wrote:

So wouldn’t another whole engine out of a wreck be cheaper?
Had to ask.

I don't know the answer to that yet. At the moment, all I have is the wrecked block and associated parts, and no paycheck (yet) to afford to do anything to correct the problem.

GreenDieselEngineering · **Joined:** Sun Jun 07, 2009 5:10 pm **Posts:** 1111

Rollover protection is just saying that the engine will rotate without pistons hitting the valves if a valve is stuck open. Most diesels do not have rollover protection as they have very high compression ratios.

The finger followers on this engine are designed to be the weak link if a piston hits a valve. We have seen an engine that failed the followers and one was wedged in the valve spring and prevent the valve from closing thus leading to a dropped valve. Have also seen a portion of glow plug keep a valve open, which also led to a failed valve.

Were the rocker arms on your engine broken?

kdlewis1975 · **Posted:** Sat Oct 03, 2009 11:40 pm

warp2diesel wrote:

kdlewis1975 wrote:

warp2diesel wrote:

I calculated the Horse Power at 228, so now we know where VM draws the line.

...not trying to pick a fight here...just asking out of curiosity.... Would that horsepower rating for the 8-valve marine engine translate to a true baseline for our 16-valve engines?

16 valve will rev up faster and have a little more with a flatter torque curve than an eight valve.
Fast revs out of a Marine engine is of no use since they run a prop.
Same block, crank, and rods, same structural limitations, that is my point.
VM like any company will employ a safety/service factor to limit failures.
When some one wants to go for the max, they are taking the risk and are flirting with destructive testing.
With the 228 HP Marine rating, we all know that we could go up to that point and perhaps a little beyond without worrying about having our engine fly apart from pure horse power out put.
I would never attempt it with out a complement of gauges.
Of course, there are a lot of DUMB@$$ stunts that will destroy even a stock engine, that idiots reserve the right to do.

Thanks for the info. I just didn't know if having 8 valves would limit the amount of horsepower the engine could make...or if they would have put a slightly higher rating on it if it had 16 valves. It's too bad we don't have a VM employee to chime in on here from time to time...I appreciate it that we have a couple of Chrysler guys here...along with the GDE guys...helps eliminate some of the speculation that goes on about various topics.

Amianthus · **Posted:** Sun Oct 04, 2009 6:54 pm

Thanks for all the replies so far.

As for rollover protection, yeah, I knew this engine's protection was the rockers. I couldn't find any distortion on the rocker. However, the keepers and the top of the valve spring were gone! There are bits and pieces in various spots. But I haven't collected them yet to see if all the pieces are there. I just figured, with an interference engine, you take your chances.

17.5:1 Hmmm..... That holds potential... I will have to do some figurin'.

As for suspecting the EGR. I am biased against the device. But seeing as how ALL of my coolant was found in the oil pan, I have to look into every interface of coolant to the engine. Oil cooler. Blown cylinder sleeve (probably blown by coolant in the cylinder and the piston trying to come up against it). EGR (where I found coolant in the intake). Et al. I am not quite sure of the mode of failure. And I don't know if I ever will. But I have a clean slate and want to start toying with ideas.

The 4bt is a whole nuther animal, per se. I can make one of those scream! But the lack of parts for this one and the wet-sleeve design make it tougher.

As for finding a used engine. I found one with 60Kmi on it for $3200. Chrysler used to sell the engine complete for $3600 brand new. Although, they have no listing for that any more. Now it's a 3/4 engine (whatever that is). Still looking.

Any other ideas would be appreciated.

I will be away from this engine for a bit. I have to go out of town for work. So it will have to sit. So I am in no big hurry. For sure.

Thanks for the help

A

geordi · **Posted:** Sun Oct 04, 2009 8:30 pm

Out of curiosity, what do they price the 3/4 engine at? I spoke with the VM reps for North America (Very nice people, BTW) and they suggested that is what I need for rebuilding my engine.

Fossil Fool · **Posted:** Mon Oct 05, 2009 12:55 am

About 3 weeks ago my CRD died also, at 90,000 miles. Right in the middle of the interstate. No hint of any problems whatsoever. (maybe it was the amsoil). Turns out the fuel injectors went, causing further damage to one of the cylinders. somehow coolant was mixing with the oil. Anyway the dealer only caught the injector issue. But local mechanics caught the engine damage. All this happened when the LOST site was down! I searched for engines and finally went with the mechanic. $5000 later I have my jeep back with a 50,000 mile engine in it. Hope this one lasts alot longer. So much for the diesel myth of longevity. Boy, am I scorned. God help me though, I still love those Jeeps. Whats that about a fool and his money!

Amianthus · **Posted:** Mon Oct 05, 2009 1:46 am

I haven't gotten a price for the 3/4 engine yet. So I don't know. And I don't know if it will be cost effective for what I want to do.

When I find out, I will post it here.

A

Amianthus · **Posted:** Mon Oct 05, 2009 2:43 am

When the knocking started, my wife was on the phone with me and she pulled over right away.

She checked the oil and it was about a quart and a half low (I use amsoil too). But the hammering was still there. I put my hand on each injector and I could feel that it was #2 for sure.

The next day, thinking (and hoping) that it was a plugged fuel filter and the lack of fuel supply was causing the rail pressure to drop out and cause a misfire, I changed the filter and added one of the kennedy lift pumps I had laying about. After trying to restart it, and having it size on the restart attempt, I thought I would pull the injectors to take a look.

One, three and four all came out with ease. #2 needed the engine hoist to get it out of the head. When it came out, I knew I was screwed. The damage made me certain that the engine was trashed.

Now after I got the engine out, and started taking it apart, I found all my coolant in the oil pan. I suspect that the damage started as mechanical (valve breaking off in the engine) and the cracked head then allowing coolant to fill the cylinder. Which then blew the sleeve when I tried to start it.

But that's my guess.

A

geordi · **Posted:** Mon Oct 05, 2009 3:11 am

Your analysis sounds about right, that really sucks.

Amianthus · **Posted:** Mon Oct 05, 2009 8:51 am

Yeah, that was one thing I had hoped it wasn't. But when I pulled #2 and saw that it was bent and smooshed, I knew the damage was more severe. Blowing a tip is rare enough. And all the parts of the injector came out with it and still attached. Albeit bent and squished. It was ugly.

I am going to have the injectors custom rebuilt and honed a bit. Not much. But just a little. Maybe enough to give about 15% increase in fueling. The turbine is getting massaged as well. Bigger rotating section to help keep it spinning in it's map (and some other little tid bits to it). I am also going to stud the head to increase the clamp load. Oh and balance the reciprocating assembly too.

After that, and what I am still fiddling with, is fly-cutting the pistons and seeing if I can get a bit more lift out of the cams. I don't mind losing a point on the compression. Or a point and a half. But fly-cutting might take the compression down too far and it will run like hell in the winter. If at all. So my mind is swimming in possibilities. Then I have to get an ECM to take advantage of all of that. EGAD!!!

So it's good the engine will set for a month while I am out at work. I will be able to track down parts and figure out just how far I can go!

A

Tinman · **Joined:** Mon Apr 10, 2006 10:45 am **Posts:** 308

Fossil Fool, don't be too hard on the engine itself for your failure. The injectors are the weak link in a common rail system. If one fails, the damage can be catastrophic. All the diesel forums have examples of engines completely ruined by a failed CR injector. Currently, there is no way to prevent the flow of fuel in an injector that's cracked or stuck and usually the operator doesn't know there's a problem until it's too late and all kinds of mayhem has already occurred. Just the nature of the beast. Sorry for your troubles.

mackruss · **Posted:** Mon Oct 05, 2009 10:59 am

Wow , this is scary stuff i'm reading here. Think i need to get my CRD up to the second hand lot and get rid of it before all this happens to me and i too am left looking to find a 3/4 engine :shock:

in my part of the world could be quite scary :roll:

A - Keep the posts rolling on your mods, i enjoy reading them :wink:

Fossil Fool · **Posted:** Tue Oct 06, 2009 2:53 am

Amianthus, Your story sounds exactly like mine! It was my wife also, who was stuck on the interstate.
Wish I had the mechanical know how that you have! This car from day one has been a real learning experience. Both good and bad.
Thanks Tinman for your sympathies. So is the key to somehow keep an eye on the injectors and periodically have them serviced. I don't have a provent or sega/ but was running with the elephant hose mod. (after 2 egr replaced).
I have been pretty busy this year and have let my LOST lurkings slide. Looks like I have to pay more attention to my "club".

mackruss · **Posted:** Tue Oct 06, 2009 12:29 pm

Aren't we supposed to chuck some injector cleaner in the tank occasionally to clean the injectors or does this stuff not work

Tinman · **Joined:** Mon Apr 10, 2006 10:45 am **Posts:** 308

To my knowledge there is no way to prevent, look out for or otherwise know of injector issues in most cases. Like I said, it's a common rail thing. I think as time goes on, injectors will get more reliable. But the only way I can think of to prevent this is a way for the ECM to monitor flow to each injector and if there is too much flow, set a CEL or something. That would be very expensive and not justifiable for the manufacturer. The only thing one can do is make sure you have good fuel, as in 2 micron filtration. That's one reason why the 10 micron fuel filters on the Libby and my truck is in the trash. But there is no data to prove it helps, it's only in theory. If you have a bad but not failed injector, that is leaking fuel a little, it'll should up on UOA. But if one gets stuck open, if can wash down the cylinder, replace the crack case oil with diesel, hole pistons, hydrolock, throw a rod (all stuff I've heard of) in one tank of fuel. Engine may run fine right up until total failure. Good news is that it's fairly rare, but it does happen. Maybe in this case. :roll:

.

Diggerfreek · **Posted:** Tue Oct 06, 2009 2:09 pm

Tinman wrote:

To my knowledge there is no way to prevent, look out for or otherwise know of injector issues in most cases. Like I said, it's a common rail thing. I think as time goes on, injectors will get more reliable. But the only way I can think of to prevent this is a way for the ECM to monitor flow to each injector and if there is too much flow, set a CEL or something. That would be very expensive and not justifiable for the manufacturer. The only thing one can do is make sure you have good fuel, as in 2 micron filtration. That's one reason why the 10 micron fuel filters on the Libby and my truck is in the trash. But there is no data to prove it helps, it's only in theory. If you have a bad but not failed injector, that is leaking fuel a little, it'll should up on UOA. But if one gets stuck open, if can wash down the cylinder, replace the crack case oil with diesel, hole pistons, hydrolock, throw a rod (all stuff I've heard of) in one tank of fuel. Engine may run fine right up until total failure. Good news is that it's fairly rare, but it does happen. Maybe in this case. :roll:

.

Yeah, UOA is basically one of the only indications you may get with a leaky injector. The fuel dilution ration should be through the roof, but there are times where the injector will just doo doo it self and well

MrMopar64 · **Posted:** Tue Oct 06, 2009 6:02 pm

A failed injector on the KJ engine won't cause the oil sump to fill with fuel. This happens on the Cummins engines because the injectors are located under the valve cover and when the body cracks, it sprays fuel over the top of the valve train which then fills the oil sump. On the KJ engine the injectors are on the outside of the engine so if the body were to crack, it would just spray over the top of the engine.

In my experience working with common rail diesels over the past years, I haven't seen an injector body crack that wasn't subjected to over-pressure by some means (most usually from a pressure box that raises rail pressure unsafely).

The VM industrial engines don't really share too much with the automotive engines other than the bore and stroke - they're far from a fair comparison to the engine in the KJ. With the KJ engine, the power density is limited by the cylinder head, not only in strength (only 4 bolts per cylinder, too much pressure causes the head to walk on the dowels and warp, and also to crack) but they can't flow enough air to support high power densities without just billowing smoke which is quite frankly tacky.

mackruss · **Posted:** Thu Oct 08, 2009 4:38 am

MrMopar64

Could the performance mods that are available for the CRD contribute towards prem engine failures particularly those that may go beyond the limit of what the CRD is designed to handle.

My understanding is that the engine is tuned to operate below its max and that the performance boxes and ECU tuning are simply pushing these benchmark values to a higher level and in so doing contributing to the associated mechanical problems with the increased output.

I have always steered clear of the performance mods as a result of my understanding although I'm not against what some of the tuning boys are achieving these days.

flman · **Posted:** Thu Oct 08, 2009 5:50 am

Just wondering, was WVO ever used in this engine? This looks all to familiar to something I have seen in the TDI forum.

onthehunt · **Posted:** Thu Oct 08, 2009 7:55 pm

If you have an injector stuck open you will know something is wrong right away. It's the slow leaks that kill. UOA is useful in detecting this. This story sounds like a dropped valve which destroyed the injector. Most of these stories of blown engines all have one thing in common- They are run way low on oil and when they start making noise people just keep driving.

Blown CRD.

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