HOLSET HE431VE Rebuild kit

Find a way to make a regular turbo work...make a retrofit kit...I'd be willing to bet it's a market someone could corner!
 
LReiff said:
Find a way to make a regular turbo work...make a retrofit kit...I'd be willing to bet it's a market someone could corner!
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I wish. Those things have speed sensors and pressure sensors on them-the ECU would have a fit if it got no signal and pull fuel, or even shut it down. The ISM has a very very protective ECU-you can't even idle for more than 15 minutes with those things, they just shut down...
 
Are you implying that with speed and pressure sensors alone another turbo could be made to work? Or is there other inputs that the ecm is looking for?
 
Turbo Repair said:
Well, the rule of thumb for bigger turbos is this: the more shaft play you can feel, the more thrust bearing wear there is inside. It's not like small turbos where you can feel the shaft play and figure out how worn out the thing is. unless a turbo like this is totally gone, you will only feel a little wiggle.

The turbo probably blew through the thrust parts and then got into the j bearings. If you had coked oil, the bearings would be black. I bet they are not. You probably have thrust wear from surge, which is super bad on these turbos. Your piston groove in your bearing housing might be worn.....

If you have or had surge, you may have vgt issues and stress cracks in the turbine shaft. Hopefully you don't have the notched turbine shaft? That's another weak spot where the turbo starts to fail from surge. The turbos surge and surge and surge and surge, and they finally come apart, either at the quill or at the oil channel on the shaft.


Lay your thrust bearing down on a flat steel surface. Is the bearing deflected? I mean is it perfectly flat?

I don't want to be a party pooper-you probably have a good cheap performance turbo-you just need to figure out of your vgt system is boogered and fix it if it is. If you just clean it, it will still be boogered and your turbo will go boom....
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The compressor has a time/date stamp, it was made on 11/3/2008. So the turbo survived less than a year before failing.

I picked up a really cheap HX35, HY35, HX40 repair kit to check sizes against. The journal bearings both new and old turn out the be the same size to with in .01mm. Which make me wonder if they are even worn. Both piston seals matched in size. The thrust bearing, while physically the same size, is machined differently.

The only notch on the shaft is the one for the speed sensor, and I can't see that causing stress cracks. Maybe if the turbo was unbalanced, but then it wouldn't survive long anyway.

The thrust bearing is slightly deflected, but the is no visible wear on the thrust surface.

The only parts that show significant wear are the piston seals. I'm going to have to pick up a gallon of chem dip to clean piston grove on the turbine and exhaust side of the center housing. The oil is cooked on there pretty hard.

With the vane out I see that the inside piston ring for it has so much junk stuck in it that it won't move at all. I'm half tempted to remove it and leave it out just to see what happens. Sure, leaving it out will let exhaust gasses pass behind the vane and then out from behind the turbine wheel. But how bad could that be compared the the oil leaking past the turbine piston seal and coking the center of the vane. Causing it to get stuck on the center piston seal for it. Though the vane floats on its mounting pins so that might not work out. I'll have to check that out later.
 
How well has the HE551v been holding up...mine likes to bark/surge a little coming off the fuel

Chris
 
LReiff said:
Are you implying that with speed and pressure sensors alone another turbo could be made to work? Or is there other inputs that the ecm is looking for?
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The speed sensor is the big one. Also, the pneumatic vgt actuator would have to remain intact and zip tied to the frame rail. The pressure sensor can be retrofitted to any turbo.

The ECU needs that speed data, though...
 
Tohya said:
The compressor has a time/date stamp, it was made on 11/3/2008. So the turbo survived less than a year before failing.

I picked up a really cheap HX35, HY35, HX40 repair kit to check sizes against. The journal bearings both new and old turn out the be the same size to with in .01mm. Which make me wonder if they are even worn. Both piston seals matched in size. The thrust bearing, while physically the same size, is machined differently.

The only notch on the shaft is the one for the speed sensor, and I can't see that causing stress cracks. Maybe if the turbo was unbalanced, but then it wouldn't survive long anyway.

The thrust bearing is slightly deflected, but the is no visible wear on the thrust surface.

The only parts that show significant wear are the piston seals. I'm going to have to pick up a gallon of chem dip to clean piston grove on the turbine and exhaust side of the center housing. The oil is cooked on there pretty hard.

With the vane out I see that the inside piston ring for it has so much junk stuck in it that it won't move at all. I'm half tempted to remove it and leave it out just to see what happens. Sure, leaving it out will let exhaust gasses pass behind the vane and then out from behind the turbine wheel. But how bad could that be compared the the oil leaking past the turbine piston seal and coking the center of the vane. Causing it to get stuck on the center piston seal for it. Though the vane floats on its mounting pins so that might not work out. I'll have to check that out later.
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You need that vgt thrust bearing for sure. Did you check your bearing housing for wear?

I suspected the notched turbine shaft was for the speed sensor, but I had not checked the depth to confirm. The notch doesn't cause the stress cracks, the surge causes the cracks, and the notch is just a major weak spot, just like the threaded quill on the compressor side is a weak spot. The whole shaft cracks, but it is thinnest at the quill and the notch.

You can take the whole VGT system apart pretty easily-the allen screw that you can access at the oil drain comes out, and the arm assembly will come out after that. Just mark the position of the VGT actuator arm first so you can put things back together.
 
Signature600 said:
How well has the HE551v been holding up...mine likes to bark/surge a little coming off the fuel

Chris
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Depends on the application, really. If it's surging, it will fail like the rest, it just depends on how many hours you put on it. Needs to be cleaned/modified so it doesn't croak. I've seen he3 series, he 4 series, and he 5 series turbos fail due to surge. The only thing they have in common is the holset VGT system.
 
Cleaned...how about I just open it up farther so it doesn't surge...worked before I closed it down further to make it spool faster??

I still can't believe how far this housing will close down and choke a 5.9L engine...
Chris
 
Signature600 said:
Cleaned...how about I just open it up farther so it doesn't surge...worked before I closed it down further to make it spool faster??

I still can't believe how far this housing will close down and choke a 5.9L engine...
Chris
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won't work. If you are off throttle, the VGT system actually has to close to reduce surge. If the nozzle area (a/r) is small with no throttle, it stops the rotor from spinning freely. If the nozzle area is big with no throttle, the rotor will surge.
 
Signature600 said:
Cleaned...how about I just open it up farther so it doesn't surge...worked before I closed it down further to make it spool faster??

I still can't believe how far this housing will close down and choke a 5.9L engine...
Chris
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I measured that, there is enough travel for the vane to make contact with the shroud plate. If the tips of the vanes don't hit the exhaust housing first, didn't check for that. Which would leave a gap a few thousands wide.
 
Tohya said:
I measured that, there is enough travel for the vane to make contact with the shroud plate. If the tips of the vanes don't hit the exhaust housing first, didn't check for that. Which would leave a gap a few thousands wide.
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I think you are mixing up the functions of the VGT: if the VGT nozzle ring is all the way out (away from the bearing housing), you have the least amount of area between the turbine wheel and the turbine housing. This means that the turbine wheel will spin up faster under throttle, and it will slow down faster with no throttle.
 
I'm not, Signature600 was commenting on how he couldn't believe that a turbo that big on a 5.9 could choke the engine.

And I was saying that the VGT nozzle when all the way out runs into the exhaust housing leaving a very tiny gap. Which could choke just about any engine you could mount it too. Its also how the exhaust breaking function of the turbo works.

:/ I don't have a inside micrometer small enough to check the bearing housing, currently.
 
Turbo Repair said:
won't work. If you are off throttle, the VGT system actually has to close to reduce surge. If the nozzle area (a/r) is small with no throttle, it stops the rotor from spinning freely. If the nozzle area is big with no throttle, the rotor will surge.
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But since you don't know how I'm controlling it, you can't be sure of how fast it closes once I'm off the fuel...I have very light air pressure closing the turbo, so unless my drive pressure drops below about 10psi, the turbo stays open ;)

Tohya said:
I measured that, there is enough travel for the vane to make contact with the shroud plate. If the tips of the vanes don't hit the exhaust housing first, didn't check for that. Which would leave a gap a few thousands wide.
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Didn't figure it would close that far...thanks for the info!

Tohya said:
I'm not, Signature600 was commenting on how he couldn't believe that a turbo that big on a 5.9 could choke the engine.

And I was saying that the VGT nozzle when all the way out runs into the exhaust housing leaving a very tiny gap. Which could choke just about any engine you could mount it too. Its also how the exhaust breaking function of the turbo works.

:/ I don't have a inside micrometer small enough to check the bearing housing, currently.
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I just can't believe that closing that turbo that far wouldn't cause problems on a 915 CID ISX...seems like it would really make some backpressure.

Thanks for all the info guys, it should help me tune this thing in a little more!
Chris
 
Tohya said:
I'm not, Signature600 was commenting on how he couldn't believe that a turbo that big on a 5.9 could choke the engine.

And I was saying that the VGT nozzle when all the way out runs into the exhaust housing leaving a very tiny gap. Which could choke just about any engine you could mount it too. Its also how the exhaust breaking function of the turbo works.

:/ I don't have a inside micrometer small enough to check the bearing housing, currently.
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Oh right, I get what you are saying now. You could just use a depth gage?
 
Signature600 said:
But since you don't know how I'm controlling it, you can't be sure of how fast it closes once I'm off the fuel...I have very light air pressure closing the turbo, so unless my drive pressure drops below about 10psi, the turbo stays open ;)
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indeed I don't BUT I do know that most of the turbo problems aren't due to the VGT system being stuck in place, they are because the actuator doesn't move fast enough due to soot. It's not like the system stops working, it just stops working well.
 
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Signature600 said:
I just can't believe that closing that turbo that far wouldn't cause problems on a 915 CID ISX...seems like it would really make some backpressure.
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Well, if you look at the top of the vanes on the nozzle ring, they are half profile and there are gaps in between the vanes. You're just putting something in the exhaust stream, not plugging it up. Plus, none of us know just how far a ISX engined truck puts the vanes down. It may not do it so that you only have a few thousandths...
 
Turbo Repair said:
indeed I don't BUT I do know that most of the turbo problems aren't due to the VGT system being stuck in place, they are because the actuator doesn't move fast enough due to soot. It's not like the system stops working, it just stops working well.
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Makes since, I know if I move mine out of the normal operating range, it sticks...in the normal range, it's fine.

Turbo Repair said:
Well, if you look at the top of the vanes on the nozzle ring, they are half profile and there are gaps in between the vanes. You're just putting something in the exhaust stream, not plugging it up. Plus, none of us know just how far a ISX engined truck puts the vanes down. It may not do it so that you only have a few thousandths...
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Good point, never thought about them not closing it all the way...seems too simple now:hehe: :hehe:

Chris
 
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