The condensed version: Turbo's blowing oil, engine runs away, get it stalled out, reroute hoses to bypass turbo, coast back down trail to road, try to drive and flywheel bolts shear the rest of the way, get towed home.
The question: What are some ways to help keep oil out of the engine should this ever happen again? I have a Saab IC, thanks Pendy! Are there any centrifugal oil separators available? Would tapping the drain bolt on the bottom of the IC and running a small diameter tube to the valve cover blow enough oil back? At least it didn't run away when I was crawling up a technical rock section just a few minutes earlier or that would have been really ugly.:eek:

Man, that's the only thing that scares me about running this turbo motor in the 109. How did you get it shut down before it went boom?

You're running an intercooler, right? I would think that would help keep oil out of the engine, but I guess not. Maybe you can rig up an exhaust brake on the intake that you can close if it runs away again. Kind of a pain in the ass for a problem that doesn't really happen that often....

Good to hear you got it shut down in time.

I was just thinking about runaway engines this weekend on the trail. I have a vision of me putting the 109 on its side and it running to explosion on the 12 litres of oil in the sump. I think the easiest way would be to run a compressed cylinder of CO2 or Argon on a valve and run a switch that would release the gas into the intake, which would kill the engine instantaneously. Keeping oil out of the intake would be very hard without restricting airflow...

Edit: On drilling rigs that run diesel engines (which can encounter petroleum gas pockets releasing into ambient air that could cause a runaway condition) there is a governor driven air flap that closes to shut off airflow to the engine. This might also be a good idea, but it would have to be a very strong flap.

You aren't the only one that had a rough weekend! My e-locker motor wouldn't work - I found out in the middle of a big climb and had to get winched to the top, I ripped the rear wrap bar bracket clean off along with a chunk of frame :eek: and on the way home, a steel brake line broke, probably because it had been smashed by a rock previously, and further along the way the rotor bolts for the left wheel came loose :confused:.

Man, that's the only thing that scares me about running this turbo motor in the 109. How did you get it shut down before it went boom?

Foot on the brake HARD, put in 2nd, though I was in low range, dumped the clutch. It was in 1st when it first happened. That's probably where the flywheel bolts mostly failed, but luckily for me they sheared after the fact. I bet the thing was running 8-10k RPM.

I've thought about putting the fuel cutoff inertia switch from the RR on it to kill fuel in case of a hard crash/flop, but so far I haven't gotten around to it. I had also thought of some kind of butterfly valve on the intake to kill it. Guess I'll be looking into those things a little more now.

Use a fire extinguisher, preferably CO2. Blow it into the intake to shut the engine down. Spray until it stops spinning, and then maybe a second extra for good measure. After all, you are putting out a fire.

You may want to re-route your intake a bit so you have easy access to it.

It's not diesel you need to worry about, it's engine oil... The cutoff to the pump would probably shut it down in time, before the oil got into the cylinders, but I think that there should be something that kills it regardless of what happens. I had an overfilled-by-1-litre VW 1.6D run away on me as I was cornering really hard. The tach needle went down past 5, and made it back to 1000 rpms on the other side. The smoke plume was unbeliveable.

Maybe a cheap Halon race car system?

By the time you get the extinguisher out and into the intake, based on how that 1.6D did when it ran away, it would already be in 10 000 pieces. I think the only way to save it would be a big red button on the dash or a pull cable that releases a fire suppressant.

Hmm, I have one of those sitting in my garage that I pulled out of my race car. Only question is where the hell to put it in an already space challenged 88".

Well, you could un-thread the hose from the extinguisher and plumb a new longer hose through the firewall and into a fitting on the intake. That way you just have to pull the pin and hit the lever from right where you are seated. It would probably be the cheapest way to get the job done.

I think you can get a remote valve or actuator, you could mount the tank anywhere with a line plumbed into the intake. You could put it in the box, or (my favorite hiding spot) under the tub in the wheel box...

Well, you could un-thread the hose from the extinguisher and plumb a new longer hose through the firewall and into a fitting on the intake. That way you just have to pull the pin and hit the lever from right where you are seated. It would probably be the cheapest way to get the job done.

That would work great. Good idea. Are C02 extinguishers common enough? The only ones I have used are the ABCs.

Block of wood-sorted. Place in front of intake.

Flap would be good. Toyota diesels use similar to shut off their engines.

GM 350 engines used a flap in the exhaust steam for emission purposes. Its about the size you need. It will go inline.

Prolly need a bigger PCV system to divert oil fumes back to the oil pan instead of the intake as well.

JP

That would work great. Good idea. Are C02 extinguishers common enough? The only ones I have used are the ABCs.

They are type "BC Only". Kind of expensive, like $150 new but you can get one for $20-50 used. Kiddie PRO5CDM, General 17, Badger CD 5AH, etc. You are probably looking for a 5lb model. Might try the local commercial fire protection store.

They are not tiny, but not too big, maybe 6" dia x 15" long so you could mount it under the seat box somewhere and put the handle in the cab if you don't mind making a hole. or mount it front and center at the bottom of the bulkhead if you don't have anything there.

You could also use a CO2 tank like people are using for air tools. Or perhaps there is a way to use a paint ball gun CO2 cylinder, but you would want a fire extinguisher type valve on it.
eBay Search (http://business.search-desc.ebay.com/carbon-dioxide-co2-fire-extinguisher_Industrial-Supply-MRO_W0QQcatrefZC12QQfrppZ50QQfsooZ1QQfsopZ1QQftrtZ 1QQftrvZ1QQftsZ2QQmaxrecordsreturnedZ300QQsabfmtsZ 1QQsacatZ1266QQsaobfmtsZinsifQQsatitleZQ28carbonQ2 0dioxideQ2cco2Q29Q20fireQ20extinguisher)

The valves for blocking off the intake are all fine and dandy except if you have an air leak (blow an intercooler hose). BUT they are much smaller and 99% effective if there is no air leak.

Please post some pictures of what you come up with.

I will post pics. Looks like a trip to the junk yard is in order. That or make something myself.

I have that same IC, but mounted upside down with one of the pipes cut and turned 180 degrees. The blow by valve now can be used as an oil drain if it gets built up in there. I saw a friends 200Tdi series running happily along on it's side 2 weeks ago for a couple of minutes til he reached in and shut it down. Righted it, fired right up and never missed a beat. Spent 2 hours by the side of the road yesterday with mine cleaning thge seperator, changing the fuel filter and bleeding the whole system. Should have checked the cut off solenoid 1st, damn wire broke 1/2" from the stop solenoid.

Bugger.

If you want to keep oil from coming in the breather, then Mann-Hummell have just released an air/oil seperator called the Provent.
http://www.republicsales.com/MANN/Provent_Brochure.pdf

IsuzuRover who posts on here sometimes knows all about them.

If you want to keep oil from a turbo blow-up out the engine, that's a bit more difficult.

First pics from tranny removal.
http://www.66rover.com/runaway/sclutch.JPG
The 6 sheared bolts and broken clutch disc and pieces.

http://www.66rover.com/runaway/scrank.JPG
The rest of the bolts in the crank. I sure hope they come out ok.

Oh bugger! :eek: It looks like the threads are boogered up from here, hope the bolts come out ok, I've never had much luck with screw extractors.

Hopefully the rest of the motor and transmission are not damaged...

Left rotating drillbits are your friends, but you probably already knew that.

Bolts have got to be loose before you can shear them off like that. What were they done up to?

they don't have to be loose if you have enough torque.

they don't have to be loose if you have enough torque.

You may need to brush up on your bolted joins.
If a joint slips, then it has failed. The bolts are only there to clamp the surfaces together, the torque is taken by friction at the mating faces. You need enough clamp load that it never shifts.

This is a 1.9tdi, it'd give maybe 350Nm continuous average and maybe twice that peak. Not enough to shear those bolts in one hit, but if they get loose fatigue deals to them reasonably quickly.

I have seen things that shear with loose bolts and that looks like it just sheared. Looks like it had fastened bolts that in fact sheared. Now whether it overcame the laws of physics I'll let you determine that.

This reminds me of a run away truck I had the misfortune of being behind the wheel of. I had just replaced the turbo on a ten wheeler dump truck (cat engine IIRC, it's been years ago), but unknown to me, the driver had run the damn thing forever with the turbo spewing oil. The IC had a bunch of oil in it, and until that day, I had never seen it happen. I swapped out the turbo and took it for a test run, not knowing the IC had a bunch of oil in it. On the edge of town, moderate traffic, I run up the RPMs to spool up the turbo good. OK, cool, runs great. Let off to slow down for upcoming red light, and the thing just keeps on going, faster and faster. Oh shit panic time, turning off the key has no effect, and I am coming up fast on cars stopped at a light. I had no choice but to push in the clutch and let it spin it's guts out. It bent all the valves and grenaded the dual friction clutch. Boss was less than impressed. When I was fixing all of the broken stuff, I drilled a hole in each of the IC tanks to drain any left-over oil out. I bet there was still a couple of quarts in that damn thing.

You may need to brush up on your bolted joins.
If a joint slips, then it has failed. The bolts are only there to clamp the surfaces together, the torque is taken by friction at the mating faces. You need enough clamp load that it never shifts.

This is a 1.9tdi, it'd give maybe 350Nm continuous average and maybe twice that peak. Not enough to shear those bolts in one hit, but if they get loose fatigue deals to them reasonably quickly.
I think you need to factor in the inertia of probably twice it's normal rpm's, probably more than it's normal fuel and the fact that they were 8.8 bolts. 10.9 are replacing them. There is also a thin spacer between the crank and flywheel which probably doesn't help with shear forces.

I have seen things that shear with loose bolts and that looks like it just sheared. Looks like it had fastened bolts that in fact sheared. Now whether it overcame the laws of physics I'll let you determine that.

I see...............class 12.9 bolts in your future http://www.belmetric.com/html/catalog7.htm

I think you need to factor in the inertia of probably twice it's normal rpm's, probably more than it's normal fuel and the fact that they were 8.8 bolts. 10.9 are replacing them. There is also a thin spacer between the crank and flywheel which probably doesn't help with shear forces.

A spacer won't matter and if you want stronger bolts, then socket head cap bolts are up to grade 14.9 in some sizes.
But higher grade bolts need more torque or they'll suffer the same fate. If you use stronger bolts but the joint still moves then they'll still shear off from fatigue, it'll just take a little longer.

It seems most truckers have a run-away story somewhere. Luckily all the ones I've heard had almost happy endings. Like top gear and two feet on the brakes being able to stall it.

You may need to brush up on your bolted joins.
If a joint slips, then it has failed. The bolts are only there to clamp the surfaces together, the torque is taken by friction at the mating faces. You need enough clamp load that it never shifts.

that's in a perfect bolted joint. there is a set amount of static friction that must be overcome to spin two surfaces mounted together. in a well engineered joint, the bolts should provide enough clamping force to hold the two surfaces together with enough clamping force to keep from overcoming the static friction. the fact of the matter is, the mounting surfaces are never going to be perfectly flat, perfectly smooth, or perfectly clean which was the assumption when the engineers came up with the numbers for the clamping force.

the fact of the matter is, the mounting surfaces are never going to be perfectly flat, perfectly smooth, or perfectly clean which was the assumption when the engineers came up with the numbers for the clamping force.

Nowhere is it assumed the faces are perfectly flat, smooth and clean. Real world friction of steel on steel is about 0.3, the amount of surface in contact doesn't matter as most of the clamp load is always taken by the material just around each the bolt hole.

And nothing is ever designed with a safety factor of 1, which your post implies. Although I'm told aircraft get down to 1.1 on their worst case loads.

I've sheared a 4-bolt flywheel off on a 100hp tractor. Drilled it for 8 bolts and it's been fine since. Hardened bolts and you should be good to go.

Well, at no other times during engine removal had the bolts ever shown any signs of deformation, so I'm not too worried about it happening again, and I've had the bolts in for 2 or more years. And if friction is the major factor in the shear load, then in theory shouldn't it increase if locktite or similar were applied to the mating surfaces to keep everything from rotating in the first place?

Nowhere is it assumed the faces are perfectly flat, smooth and clean. Real world friction of steel on steel is about 0.3, the amount of surface in contact doesn't matter as most of the clamp load is always taken by the material just around each the bolt hole.

And nothing is ever designed with a safety factor of 1, which your post implies. Although I'm told aircraft get down to 1.1 on their worst case loads.

when the engineers determined the clamping force needed, i'm sure they assumed that the surfaces were completely flat and had 100% contact. just because the clamping load is near the hole, doesn't mean the rest of the material in contact counts for nothing. i'm sure they used a 5:1 or so safety factor, but that still doesn't mean that loose bolts made it fail. 8-10k very well might have been outside the safety factor anyway. engineers rarely account for imperfections in material and craftsmanship. they use numbers, not conjecture. that's why vehicle recalls happen.

when the engineers determined the clamping force needed, i'm sure they assumed that the surfaces were completely flat and had 100% contact. just because the clamping load is near the hole, doesn't mean the rest of the material in contact counts for nothing. i'm sure they used a 5:1 or so safety factor, but that still doesn't mean that loose bolts made it fail. 8-10k very well might have been outside the safety factor anyway. engineers rarely account for imperfections in material and craftsmanship. they use numbers, not conjecture. that's why vehicle recalls happen.

I'll spell it out very simply for you.
Bolts don't see any shear force until the joint slips. The joint only slips if the bolts aren't tight enough.

Static friction cares little about surface area in contact. High rpm doesn't cause flywheel bolts to shear, but it can cause flywheels to rupture and fly apart. Engineers do account for material flaws, look up "dislocations" in a materials book sometime.

Interestingly enough, I have a PDF drawing of a VW motor which I pulled from a forum somewhere.
The stock bolts in this drawing are M10x1mm, grade 12.9
The bolt PCD appears to be around 65mm.

I calculate the torque capacity of that join with the bolts torqued up to be around 1300Nm.

I would say that statement is quite true:evil:

I'll spell it out very simply for you.
Bolts don't see any shear force until the joint slips. The joint only slips if the bolts aren't tight enough.

Static friction cares little about surface area in contact. High rpm doesn't cause flywheel bolts to shear, but it can cause flywheels to rupture and fly apart. Engineers do account for material flaws, look up "dislocations" in a materials book sometime.

Interestingly enough, I have a PDF drawing of a VW motor which I pulled from a forum somewhere.
The stock bolts in this drawing are M10x1mm, grade 12.9
The bolt PCD appears to be around 65mm.

I calculate the torque capacity of that join with the bolts torqued up to be around 1300Nm.

there is a set amount of torque that a bolted joint can handle with the bolts properly torqued. the joint can still fail even with the bolts tightened properly if the forces applied, or the manner in which they are applied exceeds the safety factor the original engineers designed in. i'm not arguing that the bolts see no shear force until the joint slips. but if the joint was only engineered to see a certain amount of force, and you exceed that it very well may fail. your logic is basically saying if the bolts were tight there is no way that could have failed, and that's wrong. engineers account for material flaws, typically not manufacturing and assembly flaws however. they assume things are made to the exact specifications they came up with.

The stock bolts in this drawing are M10x1mm, grade 12.9
The bolt PCD appears to be around 65mm.

I calculate the torque capacity of that join with the bolts torqued up to be around 1300Nm.
Guess I'll have to make a trip to a specialty bolt store then as even 10.9's were hard to find. Good news is no engine damage that I've found yet. Timing changed a little, which accounts for the excess smoke and backfiring, though I'm not positive why it changed yet. The turbo on the other hand is toast. The compressor backplate bolts had loosened somewhat, causing lots of collateral damage, and being a VNT, parts aren't readily available yet, or so the rebuilder says.

Guess I'll have to make a trip to a specialty bolt store then as even 10.9's were hard to find.

These guys *know* what's up in bolts.
http://www.belmetric.com/html/catalog7.htm

Talk to Ralph Lomando - he's Mr Belmetric

Guess I'll have to make a trip to a specialty bolt store then as even 10.9's were hard to find. Good news is no engine damage that I've found yet. Timing changed a little, which accounts for the excess smoke and backfiring, though I'm not positive why it changed yet. The turbo on the other hand is toast. The compressor backplate bolts had loosened somewhat, causing lots of collateral damage, and being a VNT, parts aren't readily available yet, or so the rebuilder says.

http://www.melett.com/ do rebuild parts for VNT turbos, but they aren't particularly cheap.
That guy who was selling VNT turbos on ebay has stopped listing them, I emailled hiim back this week asking if he can still supply but haven't heard yet.

your logic is basically saying if the bolts were tight there is no way that could have failed,

I'm afraid your translation to sporkish isn't accurate.

That engine even in runaway can't produce 1300Nm of torque, with the right bolts torqued up fully it won't happen again.

These guys *know* what's up in bolts.
http://www.belmetric.com/html/catalog7.htm

Talk to Ralph Lomando - he's Mr Belmetric
I don't know if socket heads are too tall. I can get those locally, but I want hex head, which so far I haven't found.
As far as turbos, I did find Mellet. Too bad there is no place like that here, though I found a place in California that makes their own VNT replacement parts, but only sells to dealers, whom they don't list. However I found a turbo with a new cartridge for $250. I know it's new as I sold it to the guy who is now selling it. And I found a better clutch friction plate and stronger cover, so hopefully my slipping issues are over.