journal bearing turbos, oil feeding...
 

Quick question, I think I know the answer but would love for someone to be able to answer this definitively.

Do journal bearing turbos move the oil for cooling and lubrication with their reciprocation?

Jaden

They don't reciprocate.....

don't be a douche...
 

With their spinning then...****...

No. They're not a pump, they require a pressurized oil feed and an unrestricted drain.

also, the oil has to drain by gravity back to the sump, above the oil level, or you need a scavenge pump.

since we are on this topic,

how does one know how much oil pressure or the amount of oil that is supposed to go to the turbo??

i know ball bearing turbos require a restrictor and journal bearings, not, but i also know someone who purchased an ebay turbo and said he had to run a restrictor on his journal bearing turbo as well cause the oil was being pushed out the seals from too much oil pressure?? he has had that same turbo for well over a year now since the restrictor installation problem and smoke free now

so i know restrictors come in different sizes too so how would you know? too little restriction and it would leak, too much restriction and you risk turbo damage

Probably because our cars run such high pressures when cold.

I don't think most other cars run 100+ lbs pressure at cold idle. This high pressure probably is what blows through the turbo seals on some journal bearing turbos without restrictors.

Also, they probably work fine with the restrictos because our oil is so thin, at operating temps the thin oil probably adequately slips through the restrictor, enough for the turbo at least.

That's my guess.

don't be a window licker
 

I can't help it.

True, I should have specified that better :)


Usually if oil is pushing past the seals on a journal bearing turbo, the drain isn't flowing enough.


Ball bearing turbos are a different story.


Also, fun fact, there's no conventional seal on a turbine shaft, it's a labyrinth seal. Because of this, people think the seals are bad when it's really a drain problem. Or when you hear "it just needs the seals replaced, it has no play" it's BS as the other way they leak oil is if they have play.