Jump to content

6.0 turbo vane damage ?

Rate this topic


Recommended Posts

2005 F-550 71,000 miles wrench light on at times, overheats under load.  P0069 map correlation, p0234 over boost p0299 under boost. When wrench light on no power cycle key then works fine. Found unison ring rusted slot very worn. But also found the vane tips damaged. I realize I have two problems but just wondering what your thoughts are on this turbo.

 

6.0 vanes

vanes 2

 

Link to comment
Share on other sites

High EGTs will melt the turbine, most of the trucks I see this in were clearly overheated by evidence of fuel in the coolant, blown headgaskets or the occasional EGR cooler.  One I saw was FOD from a missing exhaust valve.  Anymore I always crack open the turbo early in the repair process to check the exhaust side, I've gotten burned by that a few times in the past. 

 

Some will insist it's possible for a worn out vane tab to allow the vane to contact the turbine but I'm not so sure.  I'll have to take a measurement to see how close the turbine can possibly get to the vanes when they're fully open. 

Link to comment
Share on other sites

Overspeeding the turbo will put it out of it's efficiency range so I suppose anything is possible (where a turbo is most efficient will result in the coolest EGTs).  Towing or heavy loads could easily be a factor that pushes it over the edge. 

Link to comment
Share on other sites

That is wild! I have NEVER seen anything like that. Any time I have come across a damaged turbo its because of something breaking or debris. At this point I am of the belief that current OEM calibrations on this engine will take measures to slow the turbo down when over boost conditions are reached.

Link to comment
Share on other sites

Overspeed and over boost are not always the same thing.  You can overspeed the turbo if the vanes are closed too much and normal boost levels are achieved.  Obviously stock boost can be achieved at a range of VGT positions but only one spot is going to be optimal. The EBP sensor plays the main role in this and as we know it's critical it works properly.

 

I spoke to the guy who does my turbo machine work/balancing and he speculated that vanes closed too far could potentially act like a blow torch.  High EBP and high EGT go hand in hand and the high EBP is being accelerated across the vanes.  In the bottom pic on the original post it appears the middle of the vanes are actually caved in, I don't think this is just from FOD.

 

I was going to run my VT365 turbo on my truck but after giving it some thought I don't think this is a good idea.  I think with stock powerstroke tuning this could be a recipe for disaster for all the reasons given above.  Too small of a turbo. 

Link to comment
Share on other sites

Overspeed and over boost are not always the same thing.

Understood. But, I would think that if the turbo or the EBP were acting up to allow this to occur (and this damage does not happen instantly) I would imagine that the calibration/PCM would have tried to take some action that would have been noticeable to the driver and at the very least, set a code and turn on the check engine light pointing the tech in the direction of the cause. Whatever it is, it's a rare failure and find indeed.
Link to comment
Share on other sites

Oh I agree that the driver would definitely know something is wrong via check engine light or reduced power. That isn't always enough to get them in the shop though.

 

This was the last turbo I found like this. Definitely an overheat caused by driving too long with blown headgaskets.

image.jpg

Link to comment
Share on other sites

What kind of rebuild are you looking for?  I've been doing my own for a while and just passing the savings on to my good customers for the cost of parts.  A 6.0 turbo is about as easy as it gets as long as you can find parts (ebay).  Media blast everything clean and reassemble.  A Garrett turbo rotating assembly isn't balanced with both wheels attached, each individual piece is balanced and then assembled.  Most of the times this is well within OEM specs so you really can't assemble a bad one.  Ford Remans are assembly balanced though so before you take one of those apart you need to index the compressor wheel to the turbine shaft.  Also you shouldn't mix and match rotating parts from an OEM turbo and a reman. (Lets say for example a compressor wheel that is balanced as part of an assembly might not be balanced on its own)

 

I cracked open a couple 6.4 borg warner turbos to have a look and I won't be doing that again.  They are much too labor intensive to risk screwing one up.  At least if I botch a 6.0 turbo (it happened) I can have it out in 15 minutes. 

 

You can buy new VGT vanes, unison ring and a seal kit all on eBay.  Even aftermarket turbines and compressor wheels are around if needed.  They'll work just fine in stock applications. The hardest piece to find if damaged is probably a turbine housing.  Once a vane pin gets broke that's about it, you need a whole turbo.

  • Like 1
Link to comment
Share on other sites

 At this point I am of the belief that current OEM calibrations on this engine will take measures to slow the turbo down when over boost conditions are reached.

I will agree with that statement. I've had 2 03's with the latest calibration and severely stuck turbos that I have witnessed the egr valve opening and closing rapidly when they were over-boosting. (Causes one hell of a nasty surge.) I'm kinda shocked they didn't derate. And I know that the 05 and newer will derate when they detect over-boost.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...