Nigel, The reason why turbo oil return is taken directly back to the sump is that the oil flow levels are high and could a) swamp a breather and b) cause frothing and ultimate "mayonnaise" build up in the crankcase. The design criteria is straight forward - return the oil to the sump below the stipulated oil level. This can if necessary be achieved using a tube but keep it out of the breather as this should have some form of separation system, depending upon the age of the engine.
In my experience on diesel turbo's over 40 years, 1.5 mm end float is excessive, 0.5 mm probably being more realistic. High end float suggests that the turbo has been run short of oil and consequently has worn out the end float thrust bearings. Too long now since I sized a turbo to remember the requisite oil flows - these should be available on line from the turbo manufacturers - but bear in mind that the turbo is normally fed before the pressure relief and will likely drop oil flow rate to the bearings. Take care! Hamish -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of nigelp Sent: 04 February 2012 13:48 To: Quantum Owners Group Subject: [Quantum Owners] Turbo Oil Return Advice wanted please, regarding my turbo onto blacktop Zetec project. Engine's out and gearbox being refurbed. Was planning to do the turbo oil return similar to Jim's but ...... As my turbo is sitting near the top of the engine, above and away from the crankase breather I plan to keep the breather (adding a heat shield), is there any reason why I can't weld an oil return pipe onto the breather? A 13mm oil return seems insignificant compared to the size of the breather hole. This would save me having to remove the sump, which is the two part steel base and alloy unit, drill the block, machine the outlet etc. Got into a dispute with the guy who sold me the turbo, he said 1.5mm play in the shaft and two bolts broken in constituted perfect condition, (the ad said perfect condition and no shaft play). E Bay have just ruled in my favour and its going back. Now on the look out for a turbo again. Thanks. Nigel -- You received this message because you are subscribed to the Google Groups "Quantum Owners Group" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/quantumowners?hl=en IMPORTANT NOTE: All information presented herewith is provided on an "As Is" basis, without warranty or the implication thereof. Neither the Quantum Owners Club nor the individuals associated with the Quantum Owners Club or in the preparation of the above information shall have any liability to any person or entity with respect to liability, loss, or damage caused or alleged to be caused directly or indirectly by the instructions contained within this or related message(s). -- You received this message because you are subscribed to the Google Groups "Quantum Owners Group" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/quantumowners?hl=en IMPORTANT NOTE: All information presented herewith is provided on an "As Is" basis, without warranty or the implication thereof. Neither the Quantum Owners Club nor the individuals associated with the Quantum Owners Club or in the preparation of the above information shall have any liability to any person or entity with respect to liability, loss, or damage caused or alleged to be caused directly or indirectly by the instructions contained within this or related message(s).
