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hi I just finished my installation of my holset hx35w on my rb25neo.running it top mount an externally gated just finished if off today an I have a problem it starting to blowing smoke I had the turbo checked over before it was installed it had next to no bearing play front an rear wheels were in excellent condition no scratching or chips we had the turbo apart an it had no signs wot so ever that it had oil being blown out of it now since I ran the car for about a hour an an pulled of my air intake an intercooler pipping an wipped it with a paper towel an there was no signs of oil residue any were I can't work out why it's blowing smoke wan it was installed I made up new 19mm oil return lines but as for the oil feed I'm still using the original solid rb25 oil feed line any help would be appreciated cheers

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first off as for the smoke at idle its minimal to none that I give it a hit it blows a lot for about 2 seconds than dies down to almost nothing again I unscrewed the o2 sensor an it did have a little oil on it....

as for the next question I believe it's a journal bearing an I was goin to buy another oil feed line tomorrow an see if that helps it at all

I will get a new oil feed line tomorrow but could it be that the oil return line is to small from wot I've red up these turbos do need a pretty large oil return line... is there anyone else that has dun one of these turbo conversations lately

You will need a oil restriction free feeding line for this turbo. Factory oil line has a oil restrictor in it, might have damaged the bearings already.

Get a proper dash 4 hose with speed flow connectors for the feed.

Make sure the oil drain pipe is not capable of storing any engine oil any where.

Make sure engine breather can breath freely (photo have shown that it is), crank case pressure can also cause oil flooding issues to the turbocharger.

If above don't help then this turbocharger do needs to be looked at.

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yea from wot I've red up using the holsets u tend to need to use much larger oil return lines... wot rubber line do u use as a oil return

I dont use a hose ive got full steel line i made up with id 19mm with one continoius bend going into a 45 degree silicon joiner off tge block. I dont trust hoses on high mounts since they sit to close to the manifold.

thanks for the help guys I really appreciate it I'm hoping the turbo hasn't been damaged I've only ran it for about a hour an about 50min of that was it sitting there idling but after that I pulled of the intercooler an air intake an there was no sign of an oil in it is it possible for the turbo to have a blown seal an only be leaking out the dump pipe... will upload a pic or the oil return tomorrow an see wot use think

I dont use a hose ive got full steel line i made up with id 19mm with one continoius bend going into a 45 degree silicon joiner off tge block. I dont trust hoses on high mounts since they sit to close to the manifold.

that's wot I made up aswell a solid 19mm steal tube an a 90 degree bend using a rubber hose at the block

Yeah if u only blow rear seals it will only leak into exhuast. Just out of interest what size return did u read holsets need?

every were I read just recommended using a larger return just due to the size of the turbo

You will need a oil restriction free feeding line for this turbo. Factory oil line has a oil restrictor in it, might have damaged the bearings already.

Get a proper dash 4 hose with speed flow connectors for the feed.

Make sure the oil drain pipe is not capable of storing any engine oil any where.

Make sure engine breather can breath freely (photo have shown that it is), crank case pressure can also cause oil flooding issues to the turbocharger.

If above don't help then this turbocharger do needs to be looked at.

This is the best advice. Stao knows his turbo problems, and has seen quite a few bush core highflows fail from lack of oil flow. The stock banjo needs to be drilled out at the very least. I go 2.5-3mm usually, drilling through the .9mm stock restrictor.

thanks for the help guys I really appreciate it I'm hoping the turbo hasn't been damaged I've only ran it for about a hour an about 50min of that was it sitting there idling but after that I pulled of the intercooler an air intake an there was no sign of an oil in it is it possible for the turbo to have a blown seal an only be leaking out the dump pipe... will upload a pic or the oil return tomorrow an see wot use think

I have seen a bush turbos fail within 50k's from similar stock restrictor issues. At least check the shaft play both ends of the turbo.

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