Engine/Transmission (1994 - 1998) When the turbo lets go....

[JGheen]

Just had a question for when a turbo comes to the end of its life. Mine has not blown up or anything but actually my cousin lost another turbo in his first gen '93 auto and I had to ask a few questions about it. So if I am at high boost and the thing blows up, obvioulsy I would shut the engine down ASAP, but what are the chances of some of the turbo pieces getting into the engine? Is there enough vacuum at idle pull metal pieces into the intercooler, through it and into the engine? Just what are some basic tips in protecting the engine, other than thouoghly cleaning the entire intake passages, when the turbo draws blood?



Thanks guys,



Joe

 

[chrleb1]

It would be extremely hard for a piece of metal to make it all the way through the intercooler and back up the intake pipe. But if it were just a small shaving, it might make it. I don't know if it would do any damage though.

 

[PKemp]

If... ... If the turbo lets loose the chances of getting wheel parts through the air tube into the intercooler are fairly good. All the way thru the intercooler into the intake itself..... very very slight, but not completely impossible. Anything that small probably would not create any significant damage anyway, but I have seen bad things happen to the tops of unsuspecting pistons from a BB sized fragment. The biggest problem is the intake side of the intercooler. Remove it, all the boots and flush everything backwards many, many times. The real problem is oil seal failure. If your driving and it goes, the engine will start sucking oil right out of your oil pan thru the turbo oil feed lines, turbo, and into the intake. The intercooler will become an instant oil reservoir packing in oil and feeding it to the engine. Diesels will burn engine oil just as well as regular diesel. Turning your key off will not shut the engine down since the oil (fuel) is bypassing the shutdown solenoid valve straight into the intake. This is called a runaway and usually leads to catastrophic damage. If you have a manual transmission, put it into low gear instantly, jump on top of all the breaks you can find and stall the engine out. If you have an automatic, pop the hood, if your quick enough, snatch out your trusty bowie knife and cut the intake hose just in front of the intake manifold connection and yank the intercooler side of the boot away from the manifold to stop the supply of oil (fuel). This by the way is dangerous and should not be attempted by the faint of heart. Or slam it into D-1 nail the breaks and pray. If you survive a runaway and manage to shut the engine down before failure and get it home, remove the intercooler and flush it out backwards with Calgon dish washing detergent. We use this method in our big diesels here all the time. Calgon will completely remove the oil from all the components involved. Flush a couple more times with COLD water and let dry out and reassemble. Just make sure you get all of the oil out of the intercooler or it will runaway again as soon as you fire it up. Then shop for a better turbo... .

Happy Trails, I hope this helps... ... .

 

[1dslram]

Pieces from the wheels can range from powder as it grinds on the housing to pieces of the fins and shaft. The real problem is removing the intercooler and getting it clean. You don't want pieces working their way through the intercooler and into the engine. As PKemp says oil is a major problem, and can be next to impossible to wash out of an intercooler. We started with a 5 gal. bucket of non flamable solvent and then switched to Dawn dish detergent. We strained the liquid between washes through a S/S screen oil filer.

Bruce

 

[JGK]

I think Drawson will give you a first-hand testimonial to the fact that an exploding turbo will send parts all the way to the cylinders and take out the motor. His HX55 (or was that a 50) did, as I understand it, while doing a dyno run at the Edge in Ogden, UT. He's now finally back underway with a new, very nicely enhanced engine. But no more HX50/55's.



Dee, are you out there?



-Jay

 

[DPinkston]

Being new to turbo diesels, I have given the runaway situation some thought. I have read about some people smothering them out by blocking the air intake, which will work if you don't have a BHAF, AFE, K&N, etc. , and can completely cover the intake point. Wouldn't a practical alternative be to carry a pair of vise grips adjusted so that it could be clamped to the oil line running to the turbo, stopping the oil feeding the runaway? I am not sure how long the engine would run with the oil that is already in the tubes and intercooler, thus further turbo damage may result from running with no oil, and maybe that's why I haven't seen this method mentioned. But if you have one of the aforementioned situations where you can't block the intake it may be the only way. Of course if you did this you would need to adjust the vise grips in advance, not use them for any other purpose, and keep them in an accessible place.

Would this work? Has then been done before and I'm just behind the times (read: uninformed)?

Danny

 

[PKemp]

All of these solutions are to some extent impractical and a few, admittedly, outright dangerous. The safest way is to stall the engine. This is obviously easier to do with a manual than an automatic. Practically, you should not open the hood since it puts you in close proximity with a potential bomb. We had one come in here in a dodge service truck on the end of a tow truck, where the turbo actually disentegrated and a piece went thru the passenger side battery and a piece hit the alternator. The resulting sparks ignited enough escaping hydrogen from the battery to explode and blow off the entire front quarter panel of the truck. A true disaster but an extremely rare one. Remember first that turbos, even exotic ones should last under normal wear and tear for 500k or better considering that the oil is changed frequently and you use good filters. Every effort should be expended to keep EGTs down (good air flow, big intakes (AFE) and exhausts (4-5"). Heat is a problem for long turbo oil seal and bearing life. We have holset turbos here that have lasted 1. 2 to 1. 5m miles and still have seals intact. Its like saying: will I get run over today crossing the street? The odds are that you won't. The same with turbos. For the most part they are extremely well made and reliable. But you can't say they will never fail. Everytime you change your air filter, pull off the boot to the turbo and inspect the wheel for "play". Look at the oil feed line connections and inspect for oil leaks. Change your oil regularly, use good oil and good filters. Unless your a dyno smashing ground pounder your turbo should last longer than your truck. If your a "wild man" good luck, check more often, cover your turbo with a kevlar explosion blanket and install a manual "guillotine valve" between your intake and boot.

Relax, enjoy the day, don't worry about it. Think more about talking your significant other into the expenditures necessary for the next "bomb". :-laf