Turbo rebuilds (according to Garrett) are neither suggested nor possible, as they do not sell any parts for our VNT-equipped hairdryers.
Some of you may know that a few months ago, I suffered yet another stock turbo failure. This one was less catastrophic, as it started making noise rather than just seizing up and snapping the turbine shaft off. I was able to discover the oil leak before anything had happened to the engine, and top it off so I could limp it home. The turbo shaft had developed a small amount of side-to-side play, and only just barely contacted the housing on the compressor side, doing a miniscule polishing rather than any gouging of the housing. The compressor wheel vanes are *just barely* sharpened on the edges from the contact.
So... This turbo was pulled from service when I discovered the shaft play (I estimate about 1/64 to maybe 1/32 of an inch side to side, but I consider ANY to be unacceptable) and shelved while I looked at options. The "brand new" turbo went back into my engine, where it resumed some funky performance problem it has had since the day I bought it - Papaindigo and Lgoodbar have now both experienced this turbo's behavior, and might be able to better describe it than I can. Simply put, it doesn't build boost in a linear progression, and it likes dumping the boost to 10psi or less on shifting to third - every time. If you slow down from 40+ to less than 30, then go back onto the pedal... You don't get boost, you get a huge cloud of smoke behind you and no vroom. The boost rises VERY slowly while doing this, until it hits 19/20... Then spikes to 25+ and you rocket away. Very bad turbo, but I don't know why.
I was informed by Garrett (through an injector service shop I trust) that the only option was a new unit (no core charge) for $1080. Declined, thanks. I heard on here about a possible rebuild kit from BAE for about $60, $72 with shipping. I'm willing to gamble with that amount, so I ordered it, and after a 5 day shipping delay, he mailed it out and I finally got the parts kit - With no instructions at all.
Papaindigo was here in Savannah to learn and assist with the timing belt job on Lgoodbar's CRD (Which was a rousing success, and a lot of fun) and had offered to help out if time permitted to play with the rebuild kit. We had time today, so here is the full writeup of the rebuild.
The turbo cartridge came apart fairly easily, and didn't show any obvious shaft damage on any of the components. *most* of the parts were in the kit, but there were 3 minor issues or changes - The "big ring" under the top was a slightly different design, the original had a small washer that set into the top (compressor side) and closely surrounded the shaft, while just under that was a small ring around the shaft that filled the rest of the space of the big ring's larger shaft hole. The new version retained a small oil hole in the underside, but had no inset for the washer. The small ring fit perfectly within the larger shaft hole just as on the original... BUT, there was no replacement small ring in the kit. I had to re-use that part.
In the top cover (the backing plate of the compressor side, where the 4 screws are visible) there is a top-hat shaped washer or bearing that fits into a larger hole in the cover, with a snap ring to retain it. The kit had some similar items, but the "brim" on the top hat perfectly seated into a recess on the underside of the cover. The replacement kit's option was a larger brim, and would not fit - I also reused this component.
Under the "big ring" is the main sleeve bearing. This is (somewhat to my surprise) held in a fixed position by a small disc with two pins sticking out of it. Both these components WERE in the parts kit, along with the new big ring. The original sleeve bearing was identical to the new one, save for three narrow grooves near the middle of the bearing running around the outside - The grooves had no holes or other channels in them, and appear almost cosmetic. The retaining pin / disc part was identical to the new part.
Re-assembly was not difficult, and we cleaned everything with q-tips and re-oiled them with fresh tips and oil before fitting it all back together. The result - The center cartridge now has ZERO side to side play, and PapaIndigo described the end-to-end shaft movement as "half a sheet of paper thickness" or so.
For me, the real test is answering the question, "would I be willing to install this in my CRD and run it".... And I have to say yes. I'm not going to install this at the moment, just because while the other turbo IS being annoying, I am working on getting one of Keiths and use this as a spare in the meantime. I do think that repairing these turbos is a difficult choice that will need to be made with consideration of how badly the old one failed... But if they are caught before any real damage is done... It should be possible to rebuild them. Just scribe the housings before you disassemble the two shells, B/c the position DOES MATTER for the function of the vacuum motor. Also don't adjust anything that is painted shut, like the two VNT stop screws. That is just asking for problems, and these are fragile enough as it is.
_________________ Proud supporting vendor of LOST Jeeps TRAVELING CRD TECH. I come to you! Need help? Just ask! I've taken it apart more than most. Email jeep [at] maincomputer [dot] com - BOARD MESSAGING IS BROKEN Over 225 CRDs currently driving with my valves, timing belt, rockers, or ARP Studs. Bad noises = REALLY bad things.
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