turbo rebuild, pics

[skr]

i'm in the proces of rebuilding my old turbo. the bushings( brass i guess) are extreamly worn, i'll have them done at work but first i got to get a material analysis on them,hopefuly free of charge. the front seal ,behind the impaller seams ok but i know it's not because the turbo was spitting way to much oil in the intake so it will probably be redone too. my question is how fast is it spinning? the machinist from precision tools department who is going to redo the bushings asked me and i didn't realy know what to tell him. i told him it spins realy fast but i guess he figured that himself :) so, anybody know some numbers? the turbo is suposed to be made by garret and is puting out 1,8 bars of boost.

[Rus]

Quoting Howstuffworks.com:
"The turbine in the turbocharger spins at speeds of up to 150,000 rotations per minute (rpm)"

Link: http://auto.howstuffworks.com/turbo1.htm

My $.02

[joshua43214]

On a gas powered stock turbocharged car, normal rpm is up to about 120k rpm, mostly in the 40-80k rpm range for normal driving Getting a turbo over 100k rpm requires aggressive driving and they seldom cross 120k on the street. the speed of the turbo is depandant on the exhaust gas velocity, which is dependant on the engine rpm (more or less).

Deisal turbos tend to run at much lower rpm, either way, in my experience, most turbo repair shops can't get them over 80k rpm for testing. I'm impressed you managed to wear out a deisal turbo, never had to deal with them much on BMW's, but the MB ones where pretty much a lifetime part, Ive seen them with 400k miles on the old 300d's.

Just have them spin it to about 60k rpm and you should be fine is my geusse.

[Jon K]

I'd balance it for 100,000 rpm... that's what my blower does. Also, the BMW turbos are KKK not Garrett. The bearings you are talking about are typically easy to just replace. Make sure to check the shaft for hairline cracks. Sometimes you cannot see them - get real close and stare at it.

[skr]

thanks for the input guys,
jon k: don't know where i got the ideea that the turbo is garret, thanks for clarifying that. the shaft was lab checked (microscope and penetrating spray) and it seams ok. i whould buy the bearings but the rebuild places around don't sell them separate and i got no idea where to buy them from.

joshua43214: it's probably been rebuilt before( found ugly sealent on the drain pipe). i know diesel turbos are supposed to be quite durable but i've seen passat 1.9 tdi turbos fail at 150k, and audi fail at 170k .on the other hand i have a friend with a 240td MB with 600k km on it running the original turbo.guess MB ones are better. rebuild shops offer a 3 year/50k warranty.

[Jon K]

hehe audi and vw turbos are the same thing :)

SKR, I know you probably don't want this idea to come out of my mouth... but for about the same money you are spending to get stuff made for it... you could upgrade the turbo to a larger unit :)

[BillionPa]

if you can, get the turbines thermal barrier coated, increases bearing life and lowers intake temp.

[Booster]

Its bearings are made from Bronze,not Brass.
..........Vincent;)