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I had a Ford mechanic tell me that the stainless unison ring out of a duramax will resolve the turbo issues with the VGT PSD turbo. I searched around an couldn't find anything. Has anyone else heard of this.
Thanks
Thanks
Unison ring out of a Duramax?
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There are 2 surfaces where rust is a concern. The unison ring and the turbo body on which the unison ring slides. Typically the turbo body gets so pitted that the sliding of the unison ring is inhibited, causing the problems and not the unison ring rusting. I wonder if a ceramic coating could be applied onto the the turbo body. That along with a stainless steel unison ring would REALLY get rid of the issues with a VGT.
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IIRC the Dmax and PowerStroke turbos are both VGT made by Garrett.
Why would one have different materials on the inside???
Why would one have different materials on the inside???
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Did Ford/International have it first? Maybe they saw the problems and requested it for they're turbos.
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I've been giving some consideration to a coating on the turbo for a while now. I think the standard ceramic coating you see on exhaust is too thick and not uniform enough for a tight tolerance wear surface. However when I was drag racing there was a ceramic coating some people were applying to the crank journals for increased lubricity. I need to do some research on that product to see what the nominal thickness is.
I think if you were to coat the housing and the ring, or replace the ring with a SS one it would definitely alleviate rusting and possibly due to the smooth surfaces would decrease adherence of carbon.
edit: Here's a site I found with some info on dry lubricant ceramic coating
CIC Crankshaft coatings
On a side note, here is an article that is written way better than I could say it in regards to why you would want to coat any part.
http://www.enginebuildermag.com/Article/2469/why_parts_get_coated.aspx
I think if you were to coat the housing and the ring, or replace the ring with a SS one it would definitely alleviate rusting and possibly due to the smooth surfaces would decrease adherence of carbon.
edit: Here's a site I found with some info on dry lubricant ceramic coating
CIC Crankshaft coatings
On a side note, here is an article that is written way better than I could say it in regards to why you would want to coat any part.
http://www.enginebuildermag.com/Article/2469/why_parts_get_coated.aspx
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Nice link.
I went on there and read up on their coatings. Since the crankshaft coating seems to be oil dependent for continued lubrication, wouldn't a different coating be more suitable? Say, for instance, the coating for cylinder heads? I don't know what type of lubrication this coating would give (if any) or even if the lubrication is actually an issue. There really isn't all that much pressure on the unison ring. It just slides over the surface of the turbo body. You can't even add "never seize" since that product could "gunk up the works."
Coating the unison ring itself could cause issues with the way the vanes engage onto the ring, unless that particular surface could be excluded from surfacing. I wonder if the tolerances would be so tight that the ring would have to be machined a few thousandths thinner to take into consideration the thickness of the coating applied to it and the turbo body surface that the unison ring comes into contact with....
I went on there and read up on their coatings. Since the crankshaft coating seems to be oil dependent for continued lubrication, wouldn't a different coating be more suitable? Say, for instance, the coating for cylinder heads? I don't know what type of lubrication this coating would give (if any) or even if the lubrication is actually an issue. There really isn't all that much pressure on the unison ring. It just slides over the surface of the turbo body. You can't even add "never seize" since that product could "gunk up the works."
Coating the unison ring itself could cause issues with the way the vanes engage onto the ring, unless that particular surface could be excluded from surfacing. I wonder if the tolerances would be so tight that the ring would have to be machined a few thousandths thinner to take into consideration the thickness of the coating applied to it and the turbo body surface that the unison ring comes into contact with....
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We have checked into this as well... It's a tough fix. Mostly though due to cost concerns. Our solution at this point is remove/clean/de-rust/re-install/educate. Starting and running the trucks with the VGT seems to be the biggest issue. Carbon build up is an issue we have never seen. Only rust. This seems to be caused by A: sitting for long periods without running or B: compromised EGR coolers and owners that don't fix them right away. Instead they just keep adding water to the cooling system.
Nickel plating the housings has been our best/most cost effective solution to date...
Nickel plating the housings has been our best/most cost effective solution to date...
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This is all information that I am looking into, esp in regard to the ring. Right now I think if the SS unison does exist, that might be a better alternative to coating the stock part. I need to research to see what the tolerances are on these parts and what the nominal clearances are. After that, see what the thickness is on the coating.
Barring problems with that, I would think a coating on the turbo housing and maybe even all the parts in the VG exhaust side would make the turbo more reliable and smoother functioning.
Barring problems with that, I would think a coating on the turbo housing and maybe even all the parts in the VG exhaust side would make the turbo more reliable and smoother functioning.
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The stock unison ring is stainless.
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Thanks for the info. You said you looked into ceramic coating the turbo internals. What made you reconsider?
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The costs mostly... and technical hurdles in the application process.
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Trying not to misunderstand you; are you saying that soot/etc... from long idle periods really isn't a problem?
Similar to stuff used in some weapons like POF's "NP3" with which they claim you don't even need to lube the moving parts??DieselFab said:
"NP3™ is a combination of a nickel alloy plating combined with
Polytetrafluoethylene aka Teflon. The plating components with
electroless or autocatalytic nickel is one of the most rapidly
developing metal finishing processes. The advantages of coating
uniformity, corrosion resistance and hardness are providing designers
with opportunities to protect and improve base materials in ways that
were not previously possible."
There's also Chrome/Chromoly coatings used in auto/semi-auto firearms used for hardening/longevity/corossion resistance...
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Stainless can rust. It's just not as prone to it.
You clean them when they stick. You will probably get an over-boost or under-boost code at this time.
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Not in our experience. That doesn't mean it isn't though.
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Sounds perfect to me:thumb:
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Meant to hit on this some more in that post...Would 'y'alls' experience entail just your Rigs and your customers who know that it could be a problem and therefor protect against it by not idling very often or switching to high idle when necessary; or does this experience also entail plenty of rigs owned/operated by people that don't know/care about this 'possible' issue?
I had read somewhere that Ford got rid of the VGT sweeping on the newer flashes, which would indicate that they also found it to not be an issue. Maybe I should start another thread actually polling for who's turbo vanes have siezed absent of any other situation or problems.
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