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Discussion Starter #1
So I just got a H1C from another 4btswaps member, and I confirmed that it's a 16cm exhaust housing, but I've noticed that the compressor housing is different. The turbo on the truck has the non-compression ring compressor housing that is smaller that the exhaust housing, and the 'new' turbo has the compression ring style compressor housing that looks larger than the exhaust housing. I don't know if the turbo on the truck is a 16cm housing, or an 18cm housing. I won't know until I get it off the truck, but it's my DD-er, so it's tough.

What are the performance differences between those two housings? When I get the rebuild kit for the turbo, I'll pull both apart and get the measurements of the compressor and exhaust wheels on both units. I haven't seen much discussion about the two different compressor housings.
 

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For the H1Cs the exhaust wheel (turbine wheel) should be the same size. Out of the three exhaust housings I have, all turbine wheels are the same size. The compressor wheel was different on each one. The shaft is balanced so unless you get it rebalanced you should not interchange compressor wheels with different turbine shafts. The compressor wheel matches the compressor housing so those must also go together.
 

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For the H1Cs the exhaust wheel (turbine wheel) should be the same size. Out of the three exhaust housings I have, all turbine wheels are the same size. The compressor wheel was different on each one. The shaft is balanced so unless you get it rebalanced you should not interchange compressor wheels with different turbine shafts. The compressor wheel matches the compressor housing so those must also go together.
I have now run two unbalanced turbos for decent distance (first one did about 50,000km and is still alive, but compressor damaged by dust), second one has done 5,000km since last rebuild.

I'm convinced that final turbo assembly balancing is for noise reasons, all the componenents are balanced individually and this is sufficient for everything to work for a normal lifetime.
 

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With the high rpm those suckers spin at I don't want to take a chance. Nice to hear your's are surviving just fine.
 

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With the high rpm those suckers spin at I don't want to take a chance. Nice to hear your's are surviving just fine.
Remember all the parts are balanced individually, so any residual imbalance you get is very small.
 

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Discussion Starter #7
Ok, I just got a big surprise when I pulled the turbo off my 4bt. It's a Schweitzer, not a Holset. What's the story with that? It looked just like a holset, but lo and behold, Schweitzer on both the center section and exhaust housing.
 

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I have now run two unbalanced turbos for decent distance (first one did about 50,000km and is still alive, but compressor damaged by dust), second one has done 5,000km since last rebuild.

I'm convinced that final turbo assembly balancing is for noise reasons, all the componenents are balanced individually and this is sufficient for everything to work for a normal lifetime.
the balance act isn,t for your wheel it is for your shaft. if you balance it out, your axel shaft and bearings will last longer. 300-400000 verses 50,000 km thats the differance it makes
 

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Ok, I just got a big surprise when I pulled the turbo off my 4bt. It's a Schweitzer, not a Holset. What's the story with that? It looked just like a holset, but lo and behold, Schweitzer on both the center section and exhaust housing.
Is it an S200? Those are supposed to be pretty good. They are also cheaper than Holsets (comparing new to new).
 

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Discussion Starter #10
I'll get the numbers off it and see what it is this evening.
 

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the balance act isn,t for your wheel it is for your shaft. if you balance it out, your axel shaft and bearings will last longer. 300-400000 verses 50,000 km thats the differance it makes
The shaft is balanced seperately, so is the wheel.
The only slight imbalance created when assembled is at the compressor wheel end, it's the result of manufacturing and balancing tolerances on the individual parts. They remove material from the shaft nut if necessary to acheive assembly balance.

I've had 70,000km from an unbalanced turbo which had already covered approx 200,000km prior to the compressor wheel swap. It has only been retired due to dust damage.

The Diesel Engine Reference Book (aka the oracle) mentions that assembly balancing is only a noise issue and that industrial and truck turbos didn't use to be balanced, only automotive.
My experimentation fits very well with this statement.
 

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The shaft is balanced seperately, so is the wheel.
The only slight imbalance created when assembled is at the compressor wheel end, it's the result of manufacturing and balancing tolerances on the individual parts. They remove material from the shaft nut if necessary to acheive assembly balance.

I've had 70,000km from an unbalanced turbo which had already covered approx 200,000km prior to the compressor wheel swap. It has only been retired due to dust damage.

The Diesel Engine Reference Book (aka the oracle) mentions that assembly balancing is only a noise issue and that industrial and truck turbos didn't use to be balanced, only automotive.
My experimentation fits very well with this statement.
Let me just ask you one simple question. If you are turning somthing on a lathe clamped in the jaws at 400 rpms and you put a dial indicator to measure the run out how much do you think it is possible going to move even with heavy duty bearings with out balancing it out, it happens to be the same concept rotating mass past the bearings. your manual is correct becuase they love to sell new parts. if you ever have noticed turbo bearing failure if cought in time usally allways is on the cold side first. why do you think that is? bad oil, NO, to much heat, NO, lack of oil NO, turbo bark, NO. it was caused from an unbalanced rotating mass at 50,000 plus rpms. manuals are great but they were made by the same people who sell the new parts. just giving you a little to think about
 

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Let me just ask you one simple question. If you are turning somthing on a lathe clamped in the jaws at 400 rpms and you put a dial indicator to measure the run out how much do you think it is possible going to move even with heavy duty bearings with out balancing it out
Runout (i.e. out of round) and out of balance are two very different things.
It is easy to make an item which is out of round, but in perfect balance. It is also very easy to make an item which is perfectly round but out of balance.

If you're confusing the two then your understanding of turbo balance has some problems.

it happens to be the same concept rotating mass past the bearings. your manual is correct becuase they love to sell new parts.
"The Diesel Engine Reference Book" is not a parts manual, it is the most complete collection of knowlege published on the diesel engine from inception to present. It's authors are well respected engineers who built up the bank of knowledge that is now known to all who dieal with diesels.

It is not a catalogue to buy parts from. It is not a parts manual.

if you ever have noticed turbo bearing failure if cought in time usally allways is on the cold side first. why do you think that is? bad oil, NO, to much heat, NO, lack of oil NO, turbo bark, NO. it was caused from an unbalanced rotating mass at 50,000 plus rpms. manuals are great but they were made by the same people who sell the new parts. just giving you a little to think about
The only time I have had turbo bearing failure was caused by a complete loss of lube oil. It took out both bearings completely and in a very short time.
Turbo bark causes compressor wheel damage and this can take out bearings on the cold side. But an unbalanced asssembly is not what you are making it out to be.
My current turbo runs around 150,000rpm at 20psi according to the compressor map garrett produced for it. For the last 5000km it's been doing 150,000rpm on demand and spending the rest of the time cruising at 120,000rpm. Without issues.

You really should find a copy of "The diesel engine reference book".
 

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sounds great do they sell them in the USA or should i forget just forget my years and experiance in the fuel shop working on thousands of turbos and fuel pumps and injectors of all shapes and sizes and go with THE BOOK look all i am trying to say is there is more to everthing thing than what some body has published for sale looking forward to your next comment
 

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sounds great do they sell them in the USA or should i forget just forget my years and experiance in the fuel shop working on thousands of turbos and fuel pumps and injectors of all shapes and sizes and go with THE BOOK look all i am trying to say is there is more to everthing thing than what some body has published for sale looking forward to your next comment
It's published by SAE (AKA the Society of Automotive Engineers.)
It's written by people who designed and developed the very components you tinker with.
People who know far more about this subject than you or I ever will. Your years of tinkering in an injection shop doesn't compare.

I suggest you buy a copy. You'll learn far more than you ever imagined.
 

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i think we are going to have to agree to disagree on this subject between our collective knowledge we could continue this agrument for a long time but i am done c-ya
 
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