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Author Topic: How to tell if turbo is going bad?  (Read 6717 times)
muddog16
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« Reply #15 on: September 04, 2007, 03:53:03 AM »

Brian, on ebay run a search for Detroit Diesel, you will be surprised what pops up!  There are usually all kinds of manuals on turbo's, I would get one they are cheap, in the meanwhile I'd listen to TomC's advice, it might save you some money!
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Pat

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JohnEd
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« Reply #16 on: September 04, 2007, 11:06:07 AM »

A turbo boost gauge is $25 on Ebay.  I don't know what affect running the tube 40 feet would have on the readings.  Would sure delay it though.

Dallas!  Where are you?  Somehow I am sure that one of your DD books has a number for PSI of boost at 1,800 rpm for a Huh?  That would take all the ruminations out of this and let those with a suspecion get on past that point without dumping uneccessarily cash.

Please,

John
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belfert
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« Reply #17 on: September 04, 2007, 12:26:13 PM »

I don't know that I am going to worry about the turbo right now.  Removing it would be a trick as the heat causes severe rust of the nuts holding the turbo to the exhaust manifold.  I really wouldn't want to snap off the studs going into the exhaust manifold.

There are not any real obvious problems with the turbo so I'll leave well enough alone I think.  It is unclear if the side play is normal or excessive.
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JohnEd
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« Reply #18 on: September 04, 2007, 01:55:59 PM »

Belfert,

Lot of good sense in your decision.  On the other hand..... 

Those bolts come right off after heating them cherry red.  For future ref.   Long in the future, I hope.

I still want to know what the pressure should be.  Regardless of the end play, you, or anyone, should be able to verify that the turbo is putting out the proper pressure at a given rpm.  I have seen posts where one BN said he had 27 pounds and another said he never saw more than 22.  Obviously they have boost gauges.  I should think a boost gauge would be a required instrament so you could see the pressure falling off and know why you are smoking and dropping a gear on that certain hill and your MPGis in the toilet.

Hope Dallas gets home soon.

Thank you,

John
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"An uneducated vote is a treasonous act more damaging than any treachery of the battlefield.
The price of apathy towards public affairs is to be ruled by evil men." Plato
“We can easily forgive a child who is afraid of the dark; the real tragedy of life is when men are afraid of the light.”
—Pla
belfert
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« Reply #19 on: September 04, 2007, 04:14:12 PM »

It appears that there are electric boost gauges that have a sender at the engine.  I certainly would not want to run 40 some feet of tubing to a gauge on the dash.

Where would one hook up the sender for a Series 60 engine?  My F-350 with 7.3 engine I just cut a boost line and inserted a tee, but not sure there is such a thing on a Series 60.

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larryh
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« Reply #20 on: September 04, 2007, 04:44:33 PM »

Brian

I think you have made a smart decision on the turbo. If you lose power and gets lots of smoke and can't pull a greasy string out of a goats back side then you might have a turbo going South.

Hate to see people spend money unwisely

LarryH
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« Reply #21 on: September 04, 2007, 06:04:26 PM »

Belfert,

Lot of good sense in your decision.  On the other hand..... 

Those bolts come right off after heating them cherry red.  For future ref.   Long in the future, I hope.

I still want to know what the pressure should be.  Regardless of the end play, you, or anyone, should be able to verify that the turbo is putting out the proper pressure at a given rpm.  I have seen posts where one BN said he had 27 pounds and another said he never saw more than 22.  Obviously they have boost gauges.  I should think a boost gauge would be a required instrament so you could see the pressure falling off and know why you are smoking and dropping a gear on that certain hill and your MPGis in the toilet.

Hope Dallas gets home soon.

Thank you,

John

Boost is a relative assessment, lot's of variables make up the amount of boost you will see.
What is the A/R of the turbo?
What injectors?
How is it timed?
If it's a DDEC, how is the ECM set up? and what are the running parameters?
Was the reading taken on a slight upgrade? a steep upgrade? on the flats? Heavy load? light load?
What pistons? What compression ratio? Is it just a smoke turbo? trunk pistons? crossheads? What liners were used in the last rebuild? What size are the exhaust ports?
Is the gauge accurate?
At what ambient temp were the readings taken?
What size in and out on the muffler?
Is it a turbo rated muffler?

Lot's of questions and not really any easy answers.

Good Luck!
Sorry I couldn't be of more help.
Dallas
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NJT5047
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« Reply #22 on: September 04, 2007, 06:37:55 PM »

Brian, you have a sort of boost gauge.   Your DDEC monitors the boost pressure.  It'll set a code if the boost drops.
I couldn't tell you whether to replace your turbo, but my turbo has a good bit of wear and the turbine will move slightly. 
Been that way for years.  No appreciable change. 
The intercooler would be the target of most of the turbo should it frag.  No good outcome from that. 
I'd get someone to set a known good, or rebuilt turbo on the counter so that you can compare the feel of the turbine. Most used turbos with no oil pressue will have some free play.   The hard part is deciding what's normal when feeling it by hand.  It should turn smoothly...no feel at all.  If you feel roughness when spinning it by hand, it's failing. 
If the turbo wears out, it'll leak oil, smoke, and once the boost drops from a predetermined pressure the DDEC unit will shut you down.   A CEL will set and you'll be able to download a code indicating "low boost pressure".
Then you buy a turbo...maybe. 
Before I bought a turbo, I'd be doing some comparison 'feeling. 
The local truck shop oughta have some intakes open allowing you to see what a normal used turbo feels like. 
The key to keeping a turbo healthy is to allow it to cool down for a few minutes after the engine has been operated under a load. 
To do otherwise will coke up the bearings and seals as the turbo winds down without oil supply and heat cooks whatever tiny bit of oil was in the bearings and seals.  It won't spin long when you spin it by hand, but it will spin for a several seconds after shutdown. 
You can hear the turbo spooling down when you shut the engine off.
And, if you are familiar with turbos, they make a "death rattle" when worn out... they don't smoothly spool down, they buzz and vibrate.  That is a dying turbo when you hear that.  You'll have to stand at the engine and shut it down from the engine room to hear the noise.   
If memory serves me, didn't you lose a turbo line...or maybe it was leaking?  I remember your oil filter adaptor got new "O" rings?
Good luck, JR


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JR Lynch , Charlotte, NC
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belfert
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« Reply #23 on: September 04, 2007, 07:11:25 PM »

If memory serves me, didn't you lose a turbo line...or maybe it was leaking?  I remember your oil filter adaptor got new "O" rings?

The initial thought was the oil filter adapter was leaking.  The real culprit was the oil feed line to the turbo.  The oil feed line had a hole worn in it because the clamp holding the line to the engine had broken and the jagged edge cut the line.  BK fixed the line with some couplers and a piece of brake line.

I still have the seals and gaskets for the oil cooler and oil filter adapter.  I'm thinking about replacing the seals in the oil cooler while the coolant is still out.
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NJT5047
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« Reply #24 on: September 04, 2007, 07:55:18 PM »

May want to remove that patched turbo line and get a one-piece line and install.  Turbo don't need all the weight and stuff on the line.  That line will may develop harmonics due to the additional weight and crack again. 
Let me know how the turbo exams go. 
If that oil filter adaptor isn't causing any oil leakage, I'd leave that alone.  They are not know to cause problems. 
Best, JR
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JR Lynch , Charlotte, NC
87 MC9, 6V92TA DDEC, HT748R ATEC

"Every government interference in the economy consists of giving an unearned benefit, extorted by force, to some men at the expense of others.”

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« Reply #25 on: September 04, 2007, 08:03:25 PM »

For my boost gauge, I ran 1/4 inch tubing from the emergency shut down housing, (just upstream from the blower), all the way to the dash (40ft), to a $5 air pressure gauge. Works very well, with no delay. When there is no leak in the line, it should be accurate. Regardless, you get used to what it reads normally, and any variation indicates a malfunction. Works for me.
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JC
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belfert
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« Reply #26 on: September 04, 2007, 08:08:11 PM »

If that oil filter adaptor isn't causing any oil leakage, I'd leave that alone.  They are not know to cause problems. 

The oil cooler is what I would replace the seals on, not the oil filter adapter.  The oil cooler is a known leak issue on a Series 60.  I'm kinda thinking that maybe I should just wait, but I dread dumping the coolant again.
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belfert
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« Reply #27 on: September 04, 2007, 08:10:45 PM »

For my boost gauge, I ran 1/4 inch tubing from the emergency shut down housing, (just upstream from the blower), all the way to the dash (40ft), to a $5 air pressure gauge. Works very well, with no delay. When there is no leak in the line, it should be accurate. Regardless, you get used to what it reads normally, and any variation indicates a malfunction. Works for me.

My Series 60 has no blower so I can't measure from there.  I haven't looked yet to see if there is any sort of boost line coming off the turbo that could be used to measure boost
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Busted Knuckle
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« Reply #28 on: September 04, 2007, 08:25:37 PM »

Quote from: NJT5047
May want to remove that patched turbo line and get a one-piece line and install.  Turbo don't need all the weight and stuff on the line.  That line will may develop harmonics due to the additional weight and crack again.  
Let me know how the turbo exams go. 
If that oil filter adaptor isn't causing any oil leakage, I'd leave that alone.  They are not know to cause problems. 
Best, JR                                           

JR you are 100% correct that it could crack again! And I have seen them do it, but I have also done the exact same repair as I did on Brian's before. On one in particular, I know it lasted the next 5 yrs I know of, and was still like that when it was sold! And some others I did for others that I have no clue as to how they held up. So by no means am I saying it couldn't or wouldn't break again!

And Brian to tell you the truth JR has a very valid point, and yes if it were me and you had things that were in our way the last time out of the way now I'd go ahead and fix it! But if it's still as difficult to get to as before, I'd do like I told you when we fixed it ! Just remember to make it a part of your pre/post trip check out procedure! (no I didn't call it a pre-trip inspection as it's not a commercial vehicle/driver, but Brian and I did discuss things that should be looked over before & after every trip!) FWIW Grin  BK  Grin
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belfert
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« Reply #29 on: September 04, 2007, 08:50:55 PM »

When I was at BK's place I couldn't find anyone who had the one piece line in stock that could get it to us overnight at a reasonable price or was within driving distance.  I don't believe any place that was close enough for one day UPS ground had one.  I didn't want to pay as much in air freight as the part would cost.  In the end, BK said he couldn't replace the line with the one piece one without removing a bunch of stuff anyhow.

It would be very difficult to inspect this line before every trip as it is pretty buried.  I'm not sure spending the $40 for a new line would be worth it even though it is easily accessible at the moment.
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