I brought our 420 in this morning for its 1,000 hour service and found out that it needs a new turbo :crying I'm glad they found it before any serious problem, but it I was not expecting it at all. Does 3,400 hours sound like a normal time for turbo to need replacement at?
I just have a couple of questions. 1. when you transport on the trailer do you just drive up the trailer or back on the trailer? 2. If you drive up do you cover the exhaust stack that is front facing?I have heard from so guys that transport that you should cover it up because the air will spin the turbo as it is towed and that will be dry with no oil around to lube it up.
I always make sure it faces the back for that very reason. I also cover the exhaust with a bucket if there is even a chance of rain or snow. We are as carefull as possible with this machine, I guess it was just its time to go :beatsme
Just curious what a turbo is worth to replace. Just a general idea is fine.
Like you said it must just be it's time .The only other thing is to let it warm down and not shut it down right away. but i'm sure that you do that from the way your talkin. Well at least it will be an easy fix as far as getting to it.
$1,400 for the turbo and installation :eek2 . That's on top of the $1,300 we were already planning on for the 1,000 hour service. I was a little less than happy to get that call.
What do you mean by letting it "warm down"?
Yes I could see having to pay double what was planned for hurting your feelings. Do these machines have a egt gauge(exhaust gas temperature )?
I don't think it has one of those gauges.
What i mean by warm down or I should of said cool down is after you get done running her hard and you got all that hot,hot oil in the turbo let it ideal and psuh coller oil thru it and don't shut it down with real hot oil.This should be done with all turbo vehicals. I know this guy who used to let his loader idea for at least 10-15 min before shut down. How much to just buy the turbo and do it yourself?
That sounds reasonable to me. I'll probably do that from now on. Just one more thing to add to my shutdown "ritual", it would probably drive most guys nuts to watch me checking all levers, switches, and buttons before I shutdown. Thanks for the tip. EDIT- The turbo was $1,200
This is where I was going with the egt gauge. The gauge installs normally pre turbo and tells you what the temps are going into the turbo. A lot of people that have them watch until the temps drop before shutting down. On my truck the temps go from 200 at idle to 1200 full load on a long hill. After a hard workout it can take a couple of minutes to get temps back to normal. It seems some turbo's are more prone to failure than others from excessive heat. Don't know if that cat motor is one or not.
It's not so much the oil that you are concerned with cooling, it's the turbo itself. As nobull1 mentioned, when working a turbo equipped engine, EGTs will be elevated and will heat the turbo up. If the engine is shut down while these temps are elevated, there's a chance that the oil will cook on the turbo bearing leading to early failure. An EGT gauge is the best way to monitor this, but idling the engine for several minutes before shutting down will reduce the risk. It will also cool your hydraulic fluid.
The turbo needs to cool down to less than 300 degrees before you shut it off. When oil is hotter than that it can "coke", which is when it forms a hard varnish on the surface of the bearings. This accumulates over time and ruins the bearings, which is the number one cause of failure in turbos. If you have been running your machine hard just before shutdown, I would wait at least 3 or 4 minutes before shutdown (engine at idle). If you were just driving across the job site before shutdown, you might not have to idle at all before shutdown. Just be mindfull of what you were doing just before you shut it off and time your idle time accordingly. I have seen many times when someone will come up to a guy running a piece of equipment really hard and want to talk to him. Sometimes the guy will shut off the machine to talk and this is really hard on the machine. When someone comes up to talk to me, I get off the machine and talk to him so it can continue to cool down and I can still hear what is being said. A turbo that is always properly shut down should last way longer than yours did unless it had some defect. Over the road semis can go many many hours on the same turbo.
That's exactly the question that was coming to mind for me. If you just shut it down for a minute, is it as bad as shutting it down and parking it for the night? If you're starting it right back up again, is there enough time for the adverse effects to take place? I'll always idle the engine down before I shut it off, turbo or not. One of my pet peeves is when guys just turn the key off when the engine's at full throttle, and then just turn the key to start it back up again, without ever throttling back.
How can I tell the temp of my turbo? My 96 580SL does not have an EGT guage
3 minutes is a good general time frame to let it cool down.
Did you prime turbo after changing oil fiters ?
yea you need to let the turbo slow down before shutting it off....CASE backhoes have a different type of turbo where you don't have to worry about it, but CAT needs a cool down period...we learned that the hard way on our Volvo trackhoe when we burnt up the turbo
I know that in the John Deere 310SGs they have at work there's a sticker inside the cab that says that you should let it cool down at idle for 2 minutes before turning it off (I think the manual says 1-2 minutes) and if you were to stall it, you should immediately restart it and not just let it sit there with the engine hot and not running.
Our Deere 120 says the same if stalled. Ive never heard of the Case/Cummins not needed to be let cooled down. The Cummins has a Holsett turbo like the ones in the dodges.
Couple things, correct name for the gauge is a pyrometer... but ETG works, more people know it. Secondly, alot of times there is a high core charge on a turbo cause the manufacture likes to make a profit rebuilding them. Around me there are several shops specializing in turbos and they usually charge half what gettin a reman from factory costs.
Me too Digger and it's amazing how many people that call themselves operators do that. It's either total lack of respect for equipment or total lack of training. The guy that comes in and the end of the day and just slams off the throttle so he can get to his car sooner or shuts it off to get instructions so he does'nt have to leave the seat They will get a warning from me. On a normal busy day our equipment gets shut down twice, once at lunch and then at quitting time
That turbo should not have failed under normal operation at 3,400 hours. We have wheel loaders that have between 10,000 and 14,000 hours on them and the turbos have never been touched. At the moment we are having a Volvo truck engine rebuilt and it has done 14,000 hours since we bought it and it was secondhand then. There was a little bit of movement in the bearings on the turbo, so we are having it rebuilt. I agree with all the previous posts but I had never actually heard about he oil cooking on the bearings. As turbocharged engines took over from natuarally aspirated engines, it was explained to me that the engine should be allowed to idle for two or three minutes to allow the fins to cool evenly and also when an engine is revving a turbo can acheive speeds of up to 80,000rpm. If you shut the engine off at full speed the turbo bearings can actually starve for oil while it is spinning down. Even shutting the engine down at idle you can hear the turbo spinning for a little while. I think some engines even have an oil reservoir in the oil line to feed the turbo bearings on shutdown and startup. Now I am no mechanic so perhaps some of the more knowledgeable people on the Forum can help me out here. Then totally contrary to everything that has been said, nowadays most generators are fitted with turbos. When you start a generator dead cold it goes straight up to 1,600rpm and when you stop it hot it shuts straight down from 1,600rpm. Also here and it would the same over there, a lot of the SUV's and pickups are turbocharged. I'll guarantee that some of the people that drive them wouldn't know what was under the bonnet let alone if it was turbocharged or not, so I can not see them sitting there for two minutes waiting for the turbo to cool down. I know some vehicles are fitted with timers. My conclusions from this, are that today's turbochargers are probably a lot tougher than we give them credit for. Rn'R.