Ian C Posted April 28, 2006 Share Posted April 28, 2006 OK, I took my T67 off yesterday and there was no oil in it, because it drains out naturally into the block. This is normal, and to be expected. So why then do we pre-oil (or 'prime') a turbo before installing it? Why bother when it all drains out whenever the car isn't being used The turbo gets oil through it's feed on cranking and it isn't going to be spinning much before that point, so.... discuss -Ian Link to comment Share on other sites More sharing options...
bromy Posted April 28, 2006 Share Posted April 28, 2006 I would have thought it would retain a slight coating in the cartridge and on the shaft which is obviously better than zero. when these are first fitted/primed is it common practice to fill them totally full of oil? Link to comment Share on other sites More sharing options...
bromy Posted April 28, 2006 Share Posted April 28, 2006 As your new unit arrived then? Link to comment Share on other sites More sharing options...
Ian C Posted April 28, 2006 Author Share Posted April 28, 2006 Yeah, but I couldn't fit it due to a different oil feed part so the old one is back on. Yes, the parts may retain some oil coating but the shaft in the new un-oiled one spins freely much like the old oil-coated one, and the time it'll be in the car, un-oiled, and rotating will be all of once in it's whole life for a couple of seconds tops. And even then at an extremely low speed. As this time and load is unbelievably minor compared to the whole of it's life, it seems pointless (not to mention messy) to faff about trying to pre oil it -Ian Link to comment Share on other sites More sharing options...
bromy Posted April 28, 2006 Share Posted April 28, 2006 Maybe during their build they use some kind of very sticky lube to prevent any initial wear, dont know if they still do but years ago kent cams kits used to have a bottle of very sticky red lube that used to coat the cam during first start Link to comment Share on other sites More sharing options...
Ian C Posted April 28, 2006 Author Share Posted April 28, 2006 Cams I can understand, because they get some serious metal-to-metal work from the moment the engine starts cranking. The valves are just as hard to push open atcrank speed as at 7000rpm (barring boost etc but you see what I mean) Plus the oil doesn't immediately drain away, so coating them and pouring on some more once they are in situ makes sense. Still not convinced on the turbo though -Ian Link to comment Share on other sites More sharing options...
Ark Posted April 28, 2006 Share Posted April 28, 2006 ...Plus the oil doesn't immediately drain away, so coating them and pouring on some more once they are in situ makes sense. Still not convinced on the turbo though -Ian I think you've answered you're own question - oil will probably take an age to drain clean, so the used turbo will remain slightly oiled after standing around - enough to cope with start-up useage. Link to comment Share on other sites More sharing options...
Ian C Posted April 28, 2006 Author Share Posted April 28, 2006 Nope, don't agree Mainly as I'm not talking about the oil status of the turbo at any time other than the first time a brand new un-oiled turbo is installed. The cam oil doesn't drain away because it's got lots of valleys and bits to reservoir the oil in. The turbo cartridge hasn't got these, so I reckon it'll drain out, especially with hot thin oil, in a couple of minutes if not a couple of seconds. Yes there will be a coating left, to a degree, but that's also part of my point - the oil will be back in the turbo in seconds on startup and it'll be performing very light duties at that time, that's how it's designed and how it works, so why go through any rigmarole to pre-oil it the first time it's ever used to avoid about 2 seconds of non-oiled gentle spinning? -Ian Link to comment Share on other sites More sharing options...
JustGav Posted April 28, 2006 Share Posted April 28, 2006 Two minds with this one.... While I fully agree that the oil literally just trickles straight back down the drain pipe... due to the viscosity of the oil, some will stay around the bearing. However for the sake of a tiny bit of oil, it wouldn't do any harm to preoil anyway.... On a new tubbie, it wouldn't have any oil apart from the machining gunk they put on for cutting.. Belt and braces?? Link to comment Share on other sites More sharing options...
Guest dee_rz Posted April 28, 2006 Share Posted April 28, 2006 lol damn you guys come on i'm waiting for a nail in the cofin answer here i will soon get to this point also myself when my turbo comes and will need to know... should i do it or not bother i will for the shake of it do it as i know my bloody turbo is f-ing expensive so lubed she be i think keep going guys it's good reading Link to comment Share on other sites More sharing options...
SimonB Posted April 28, 2006 Share Posted April 28, 2006 I think it's more because on a brand new setup it would take oil a while to make its way through your new pipes and arrive at the turbo inlet for the first time. After the air is out of the oil system after the first time you've run it you'll get oil flow at the turbo inlet very quickly. Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted April 28, 2006 Share Posted April 28, 2006 I have never primed a turbo before fitting, and never had any premature wear or problems, as there is no real loading on start up, and the oil reaches it pretty quick i can't see any real problem, i know most turbos run plain bearings but there is a film of oil which is fine until the pressure builds up, and i certainly wouldn't worry about BB turbos, you only have to think about an old type two stroke engine, they run on a 40 to 1 oil petrol mix and the mains are usually roller or ball bearing and they ARE under load! and they survive. Link to comment Share on other sites More sharing options...
b_have Posted April 28, 2006 Share Posted April 28, 2006 I have never primed a turbo before fitting, and never had any premature wear or problems, as there is no real loading on start up, and the oil reaches it pretty quick i can't see any real problem, i know most turbos run plain bearings but there is a film of oil which is fine until the pressure builds up, and i certainly wouldn't worry about BB turbos, you only have to think about an old type two stroke engine, they run on a 40 to 1 oil petrol mix and the mains are usually roller or ball bearing and they ARE under load! and they survive. Exactly. I primed mine with a syringe full of oil after fitting just for peace of mind, but it felt well oiled when it arrived from PHR anyways. I'm sure most quality turbo builders would use an assembly oil. Link to comment Share on other sites More sharing options...
Soonto_HAS_soop Posted April 28, 2006 Share Posted April 28, 2006 Would it be worth running the return up and over the turbo and then back down, so that the turbo keeps a small amount of oil in it, until cranking pressure takes over? Link to comment Share on other sites More sharing options...
Guest Usmann A Posted April 28, 2006 Share Posted April 28, 2006 Never manually primed here. You can always take off the ignitor and crank it till the oil light goes out, then you have pressure. Ok thats sort of priming. if you prime it with a syringe, and let it sit, the oil will weep past the into the copm side as thier is no pressure forcing the seal to make on the oil side and intake. I knwo this cos my new PT74 dripped oil out from PT like a biotch, once running no smoke whatsoever. I wouldnt restrict or play with the drain, it might cause excessive oil buildup and the CHRA and cause it too weep ... Link to comment Share on other sites More sharing options...
Chris Wilson Posted April 28, 2006 Share Posted April 28, 2006 Two minds with this one.... While I fully agree that the oil literally just trickles straight back down the drain pipe... due to the viscosity of the oil, some will stay around the bearing. However for the sake of a tiny bit of oil, it wouldn't do any harm to preoil anyway.... On a new tubbie, it wouldn't have any oil apart from the machining gunk they put on for cutting.. Belt and braces?? Any decent turbo will be pre oiled from the ,akers as it is fed oil whn on the air balancer. I'd always squirt some engine oil down the cartridge when fitting though. I'd also have enough oil pressure on cranking with plugs out before starting so the whole oil system is primed ready for a start up on new engine. Link to comment Share on other sites More sharing options...
andrew7 Posted April 28, 2006 Share Posted April 28, 2006 Never manually primed here. You can always take off the ignitor and crank it till the oil light goes out, then you have pressure. Ok thats sort of priming. I had the same advice as that too................ Link to comment Share on other sites More sharing options...
Ian C Posted April 28, 2006 Author Share Posted April 28, 2006 I'd always squirt some engine oil down the cartridge when fitting though. Here is the apeture in the oil feed - squirt away -Ian Link to comment Share on other sites More sharing options...
Chris Wilson Posted April 29, 2006 Share Posted April 29, 2006 I use a hypodermic to fill BB turbos if the restrictor isn't removable (they usually are for cleaning purposes). Link to comment Share on other sites More sharing options...
uk-rich Posted April 29, 2006 Share Posted April 29, 2006 i too, oiled mine before fitting,then turned shaft to coat surfaces, only need to put a small amount in anyway can't see a down side to this however you look at it Link to comment Share on other sites More sharing options...
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