Turbo Rebuild Pg04

By now its taking shape a little and confidence is high. The cup should slip over as shown and the backing plate drops over top of the thrust bearing assembly etc. Be careful to make sure the thrust collar & spacer stay properly located as you start the 4 bolts into the back plate. Don’t tighten them up just yet though.

Its recommended by Garrett to get a VSR balance. Quite an expensive machine to do the job that most turbo shops don’t have. It’ll cost you around $100. The mechanics & turbo specialist that knew the sigma turbo T3 air research and serviced them regularly didn’t use this process. Most of the time it was by experience that they would judge if it required balancing at all. If they suspected it did, then into the shaft balance machine it went. 90% of turbo’s are done by this machine anyway (if done at all), so it suited me fine. I wasn’t going to, but while I was milling out the bolts and re-tapping the bolt holes on the exhaust housing, I decided to get it done. Mine was quite scaly from years of abuse so it was lightly sand blasted and balanced. Turned out it only required a light filing on the inlet turbine and that was it. Not bad for a 26 year old setup. Came in at a well spent $50.

So here it is, the part that keeps all the nasty exhaust gases out of your oil & the
oil out of your exhaust. Something that mine had well developed problems
with…Make sure its in the grove shown before you slide the shaft in. The ring will
have quite a bit of slop and even a gap but don’t worry it closes up once its in.
Carefully put pressure on the shaft to drop the ring into the housing. It should
almost seem like a ‘tooonk’ when it goes in. I used a little lightweight oil to assist.
The chamfer on the housing does the rest of the work.