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Need Help On Holset Hx35W On Rb25

Rb25detvlt

By Rb25detvlt,
in Engines & Forced Induction

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Rb25detvlt Collaborator

Rb25detvlt

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does any one no how much psi the standard oil feed runs at also could it be pumping to much oil into that an forcing oil out the rear seal will drilling a bigger hole in the standard line oil feed line an bolt help or hinder it... is it possible to have a damaged rear seal but still have no shaft play

hypergear Grand Master

hypergear

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No, it can never have too much oil that forces out of your rear seal from your RB25det pump. Because the tolerances between the bearings, bearing housing bore and shaft, limits the amount of oil flow.

If the turbocharger is flooded as in if there is a oil drain problem in which stops the oil from getting out, both compressor and turbine end seal would be leaking oil (unless it is and you've only noticed the smoking end).

In your case, because the compressor side has a collar that spins that throws away excess oil directed towards it, so the compressor end is dry. Means the bearing housing is not flooding there for you don't have a oil drain issue.

If there isn't enough oil and oil pressure going to the bearings which I definitely know the Stock oil feeding line and benjos don't. Then the shaft has no centripetal support, the rear end (heavy end) would be vibrating it self in an orbit starting with chewing out rear seal splattering oil.

^^^

Above opinion is only suited for a proper Holset turbo, if what ever installed is a knock off copy then the matter could be at a newer level of complication.

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