Quote:
Originally Posted by Benzsc1
Guys as some of you may know I am looking to build a D24T with IC and now have three turbos to ch0osse from two are the AIRresearch Turb's that I asume come as standard on a D24T the other is a Garrett AR48 which I understand is the Turb's of choice used on the later VW LT High Torque engines although that is not 100% as i need to confirm it.
I am wondering how I can check to see if they are any good one of the AIRresearch blowers has play and feels a bit like its catching on what I call aluminium mould!!! The other AIRresearch spins freely and has no play in the shaft the Garrett spins freely but has some play in the shaft TBH I have always worked on N/A cars and even TD's have not been my forte but I need to start somewhere I would even be up for re-building a turbo If i knew what I needed bothparts and toold wise.
Any help would be appreciated
Si
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Hi Si
I have stripped and rebuilt a few turbos and there is a lot of dramatic nonsense talked about them by so-called experts, i think.
I have always found a little play even in new turbo shafts - the reason is that they are plain journal bearings - you can't spin a rolling element bearing like a roller or ball bearing very fast. Journal bearings need a little play to allow for oil under pressure - the correct scenario is for the metal shaft to not ever touch the bearing/bushing metal - always be separated by oil under pressure as in a main or big end bearing.
I have found a little extra play in the shaft will not lead to any disasters or oil consumption if the seals are OK, the oil is kept clean and the oil drain is clear. Seals are ceramic or usually Viton - they should be changed as a matter of course - get them from any good bearing supplier. Balancing - I have not ever re-balanced a shaft and have had no problems, but, if even a small particle of metal is missing from a vane or hub or the shaft itself, the balance will be out and it will go bang eventually - if not sooner! Go to a scrapyard and get a worn-out turbo for nothing and strip it to find out more and get some practise. I found many fittings seized solid on old turbos so it can be useful to have oxy-acetylene or other heating gear on hand.
And if you have a good standard d24 turbo spare, I would really like to get hold of it. Mine has lots of play but still runs fine and does not burn oil but it cannot be that long for this world... Cheers, Slim.