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View Full Version : Sad Tale and a hard learned lesson



Robyn
04-08-2008, 20:02
Recently I became involved with a local fellow that was needing some encouragement along the way on a 6.5 TD overhaul.

This project has spanned many months and a lot of $$$$$$ spent.

The project was in the final stages this past week and a fire was stoked in the little creature. The initial run up proved to be problematic with what turned out to be IP troubles (DS4)
Close to a year of sitting and things did not want to come back to life correctly.
There were a buttload of cylinder imbalance codes and other issues.
After getting involved in a diagnosis it was my opinion that the IP was the culprit and recommended a swap out with a known good one.

I loaned a 5521 that was built in 2000 for the task of diagnostics.

The Ip was switched and the engine fired up and ran fine

NOW the sad tale begins.
The decision was made to run the engine with the intake manifold off to make the task easier so the loaner pump could come off easy and the original rebuilt and replaced or ???

Now the engine runs fine and the tools and such are being put away and things wrapped up for the night.

Just one last run up I am told to enjoy the sweet sound of success.

Not to be.
The valley had been carefully covered with shop rags prior to beding the little beast down for the night.

That one last quick fire up was costly.
The engine lit right off and promptly sucked 2 shop rags in, one into #5 and one into #6 intake port. :eek::eek::eek::eek::eek:

The engine stumbled and shuddered and was shut off quickly.

TOOOOOOOOOOOO late. :(
The results were devastating.
A bent intake valve on each of the holes that sucked a rag.
The number 5cylinder has a crack that is almost the entire length from top to bottom.
The #5hole sucked in enough rag that the piston cocked along the wrist pin axis shoving the cylinder wall out on the outboard side.

The crank apears fine as do all the rods and pistons. (other than 5 )
The #5 rod may be bent I dont know as yet.
The piston looks fine but I would not trust it at this point.

The casualties extended to a bent pushrod on #5 intake too.
The cam shows no sign of damage.
The bearings all look ok other than the #5 rod has signs of the extra stress placed on it during the wreck.

I can't emphasize enough folks that running these with the intake off although quite fine is a risky endeavor unless extreme precautions are taken to rid the engine bay of anything that can get sucked into a port.

There is almost no room in these engines to allow anything to pass through other than air.

This debacle although not the end of the world was costly.

Block, 1 Rod, 1 piston, 1 bearing set, heads maybe (not sure yet) 1 push rod. gaskets and a set of head bolts,1 lifter to be safe. and sundry other little crap to finish the repair.

This was a terrible end to what should have been a 200K engine.
I almost cried when I heard the news. I was on scene to survey the damage the next day and was again on scene last eavening to look over the engine now that its out and apart.

In closing

Any time you have the intake off be Damned sure you dont have stuff like rags or loose parts that can get sucked in.

Any time I need to run one with things open I have a sign taped to the steering wheel (INTAKE OPEN CAUTION) and I keep the keys in my pocket and unhook the battery if I need to leave or have the ports covered with rags or tape.

There is no second chance on this screwup.
Its one way and the outcome is bleak.

My condolences to the poor little creatures owner. He is just devastated.

I understand that a good block has been found and things will progress forward but the hurt on this one will be long and tough to forget.

Please guys, think about this one and pass this along to others that may not read it here.

My Best

Robyn

john8662
04-08-2008, 23:56
Dang!

I wonder what the damage extent would be if just paper towels were stuffed into the intake runners or layed over the holes would cause?

I don't use red rags, but have heard some stories surrounding these suckers down intakes.

Crazy that the block was lost during the process, other than the block getting ruined, it would have been an easier recovery to get it back up.

Been in a similar situation with the F-Up fairy standing next to me.

Someone will get real good at assembling engines.

Robyn
04-09-2008, 07:04
The #5 hole sucked up about 2/3 of the rag and chewed it up into a soggy compacted mess on top of the piston.

There simply was not enough room left and it apears that the piston rocked on the wrist pin forcing the piston skirt into the cylinder wall and thus the failure.

From what I can see the casting in that area was not all that thick either.

I am going to ask the owner if we can section the wall before the block becomes bait for Sanford and Son.

It would be interesting to know just what the wall thickness was.

The same trick with paper towel may have been somewhat different although there is so little room in there when the piston is at TDC all bets are off.

A set of screens over the ports to protect things is the only real solution.

In fact I do believe now that just sitting the manifold back on with maybe 2 bolts snugged up and the top hat similarly attached would be far safer.

GM lists some little port cover tools in the special service section of the manual.

Hmmmm Maybe the engineers scoped this pitfall out once upon a time

redbird2
04-09-2008, 20:01
I spoke with this guy also over the weekend I know he felt about 1" tall when he was telling me this. He had done a stellar job rebuilding this thing top to bottom it enough to make old mechanic cry that a .20 cent shop towel can kill all you hard work.

This must have been why some early diesel had screens over the intake just for this problem I had vendor few years back drop a air cleaner nut down a 6.5 NA and it got lucky it only need a head and 1 piston.

moral of the story be careful when working around open intake ports on engines

restoguy
04-10-2008, 19:58
I own a set of those 'port covers' Robyn mentioned. They come up on ebay from time to time. Until now I kind of felt like they were a waste of money. In fact, I've only used them once and I only did it then because I wanted to say I had actually used them! Now they will go on any time the intake comes off!

On a lighter, related note....a friend of mine used to be a tractor mechanic. He tells tales of dyno'ing freshly rebuilt tractors with a PTO dyno and throwing red rags into the intake while the engines were at full power! These were, of course, turbo engines and the turbo chewed the rags into little bits. He said that it would just blow fine black soot out the exhaust! I can imagine how they(the mechanics involved with this) accidentally first found out about it, but I sure as hell wouldn't have wanted to be the first one to actuall THROW a rag INTO the intake of a fresh rebuild! Especially considering what it costs to overhaul a 'big' diesel like these were. That's just balls, bordem, or both.

sturgeon-phish
04-11-2008, 06:04
I feel you pain, Monday Morning quaterbacks are a dime a dozen, but something that I've learned from work, I work in the nuclear energy field, is what we call FME, Foreign Material Exclusion area, basically is when critical systems are opened, flanges or covers are in place, tagouts to prevent unauthorized operation, and “clear area” where nothing that is not in hand can be loose or laid down in the area. I use this when I’m working at home, even on non-critical systems, like changing furnace filters. Even being cautious, I’ve had my share of mistakes
Jim

Robyn
04-11-2008, 07:14
Yup it can happen for sure.

What happened with the 6.5 in question was a simple case of excitement that all was going to be fine after a change of the injection pump.

"Just one more run up to bask in the glory of finally seeing a gob well done"

When we get excited and let our guard down this is when we get bowled over by the fickle finger of fate.

Over the years I have had my share of screw ups and have been lucky that none have been as expensive as this one.

Last fall I had to have a crew in here at the Ranch to fix my well pump which is 800 ft down.

The fellows were good workers and knew their job, but as the afternoon wore on and the last 200 feet of pipe and wire were being lowered they almost had a wreck.

I was watching the reinstall carefully and noticed that the person attaching the lift eye to the next length of pipe to be hooked on to the column and disapeared into the woods to take a leak.
Another member of the crew was lowering the lift cable and attached it to the lift eye and had lifted it to the well head.
I was not sure if the fellow in the bushes had tightened the eye all the way when he split to pee.
I yelled at the lift operator to NOT lift the column, but instead bring the last section back out and lay it down.

Puzzled at my insistence he obeyed my angry toned command and brought the section back out and down.

Once the pipe was on the ground I checked the lift eye and as I suspected it was only threaded on a few threads instead of all the way and snugged up.

This mistake could have cost dearly in that once the full weight of the pump and around 700 feet of pipe were on the eye, the few threads holding would probably have let go and the whole mess would have landed in the well. :eek:

Just a tale of woe that was caught before it could happen.

We must always be vigilant and think ahead about 3 steps so these sort of things dont happen.

As has been mentioned, Covers, lockouts and tags are the way to go, even at home on our little projects.

These can very well protect us from ourselves.


Best

Robyn

DeezilDoc
04-12-2008, 06:39
If the only thing wrong with the block is a crack in the cylinder wall Sleeve it. I have done this to an early 6.2 that my neighbor built and had no problems with it

Robyn
04-12-2008, 08:18
I would not do this on a 6.5
The amount of material between the bolt holes and the bore is so little that by the time you install a thick enough sleave to be stable the bolt holes can and will crack leaving other serious issues.

A Chevy Mouse or a Rat would definately be a candidate for a sleave but I would not do a 6.5.

This block is cracked from about 1-1/2" below the deck all the way to the bottom of the water jacket. :(

IMHO to use a block like this is just inviting trouble.

The GM blocks have enough issues even when they are totally sound, let alone after they have been through a train wreck.

Best

Robyn

dieseldummy
04-12-2008, 23:13
I would not do this on a 6.5
The amount of material between the bolt holes and the bore is so little that by the time you install a thick enough sleave to be stable the bolt holes can and will crack leaving other serious issues.

A Chevy Mouse or a Rat would definately be a candidate for a sleave but I would not do a 6.5.

This block is cracked from about 1-1/2" below the deck all the way to the bottom of the water jacket. :(

IMHO to use a block like this is just inviting trouble.

The GM blocks have enough issues even when they are totally sound, let alone after they have been through a train wreck.

Best

Robyn


Finding a good machine shop is the key to sleeving a block and having it live. I ran my origional 599 block with a sleeved cyl for 10K with no adverse affects from the sleeve.

BTW, sucks to trash a motor or anything for that matter from personal mistakes. We've all made them and know the feeling. I wish this poor soul good luck on whever the next build goes.

dieseldummy
04-12-2008, 23:14
I would not do this on a 6.5
The amount of material between the bolt holes and the bore is so little that by the time you install a thick enough sleave to be stable the bolt holes can and will crack leaving other serious issues.

A Chevy Mouse or a Rat would definately be a candidate for a sleave but I would not do a 6.5.

This block is cracked from about 1-1/2" below the deck all the way to the bottom of the water jacket. :(

IMHO to use a block like this is just inviting trouble.

The GM blocks have enough issues even when they are totally sound, let alone after they have been through a train wreck.

Best

Robyn


Finding a good machine shop is the key to sleeving a block and having it live. I ran my origional 599 block with a sleeved cyl for 10K with no adverse affects from the sleeve.

BTW, sucks to trash a motor or anything for that matter from personal mistakes. We've all made them and know the feeling. I wish this poor soul good luck on whever the next build goes.

TurboDiverArt
04-22-2008, 17:50
On a lighter, related note....a friend of mine used to be a tractor mechanic. He tells tales of dyno'ing freshly rebuilt tractors with a PTO dyno and throwing red rags into the intake while the engines were at full power! These were, of course, turbo engines and the turbo chewed the rags into little bits. He said that it would just blow fine black soot out the exhaust! I can imagine how they(the mechanics involved with this) accidentally first found out about it, but I sure as hell wouldn't have wanted to be the first one to actuall THROW a rag INTO the intake of a fresh rebuild! Especially considering what it costs to overhaul a 'big' diesel like these were. That's just balls, bordem, or both.

I have a buddy that completely destroyed a turbo cause a piece of lose duct tape got sucked into his turbo at full boost on a ¼-mile pass. This was on a 1000HP gas drag engine. I quickly put chicken wire over my open turbo inlet-bell. Lots of other guys followed suit.

Art.