One for those with mechanical/technical knowledge

**nutron** · 20th January 2011, 19:09

The hybrid turbo from Turbo Technics died after just 30 miles in the car. I switched back to the old turbo and that has been running fine since. I gave it back to them to look at and they claim particulate contamination of the oil. Clearly, if there was anything that bad in my oil, the engine and old turbo would have died long ago and both are still running fine.

I have asked repeatedly if their bigger thrust bearing would need more oil flow or pressure and they insist not. I think they are wrong obviously as there is no sign of any other matter in the turbo bearing that died except bearing material. I suspect the bearing is being starved of oil for short bursts and this is causing wear which would then be self perpetuating.

They have rebuilt the turbo claiming good will but clearly and I am still being good willed about it for now as I would like it to work. Obviously, I don't see the point in just breaking another turbo to prove them wrong, so how can I address the problem as I see it?

I have thought about drilling a second hole at a right angle to the first in the feed bolt, after that I would need a bigger pipe or seperate feed pump for the turbo.

I have considered a seperate oil tank and small oil pump for the turbo but it would be alot of work.

Open to ideas and comments

**benny** · 20th January 2011, 19:46

could you restrict the return flow slightly allowing a slight rise in back preshure leaving more oil in the bearing area ....but that would then rase the presh on the oil seals ..not awin win one this is it ? .....

**nutron** · 20th January 2011, 21:28

I considered this myself but was concerned that this would decrease the volume of fluid throught the turbo, reducing the cooling of the bearing. If the pump were possitive displacement, the volume would remain the same but too much pressure could also damage the bearing obviously. I will speak to them about that idea but they seem so insistant that it isn't there fault, I don't think they would admit fault at any cost.

**benny** · 20th January 2011, 21:41

is there noscope for a bit of water cooling to help out .... could coil a small pipe around the bearing houseing take a feed from the coolant bleed pipe area even the bleed off screw ..and return to the thermo or egr cooler area ...(thats a bit of work too tho) small oil tank and lecy flow pump might be the best way ....but room is tight ....

**DavieR** · 20th January 2011, 22:53

I'm not an expert on the set up of vauxhall turbos but do know my way round a subaru unit due to my line of work.

On that engine there is no need to increase the oil flow or pressure from the pump. However the banjo style oil feed pipe is the part that restricts the oil flow to the bearing. And depending on the turbo used, this oilway can be swapped for a less restrictive one. Not huge differences, 0.5-1mm larger, and this is usually only done when changing from a subaru unit to a much larger garrett (or similar) turbo.

As I said, not sure if this is possible with your unit, but I would run it by the supplier once more.

Davie

**mucklestone** · 21st January 2011, 01:07

To fail after just thirty miles it would have to be severely under lubricated! If the oil was passing through but was not quite the volume or pressure required it would have lasted longer than thirty miles!

I would guess it was a faulty turbo in the first place. Otherwise, if it really was that under lubricated that it failed so fast, I would give up on trying to feed it from your engine feed!!!!!

If you do go down the route of a separate oil pump, it would be advisable to find a way to take it from the engine sump rather than a separate tank. The oil is designed to run hot and it won't get as hot just going through the turbo!!!

Finally the effects of a cooling coil will be minimal. Again if it lasted on thirty miles and heat was the cause you need to get rid of more heat than a simple coil of copper pipe will do! Perhaps an inline oil cooler would be better but that would not help you oil pressure problems....

I would ask them about the pressure requirements of the turbo. Then temporary plumb a pressure gauge in, near the turbo and see if the readings are OK.

TBH it sounds to me like they are trying to cover up a dodgy turbo!!

**nutron** · 21st January 2011, 13:00

Well I am sitting here waiting for it back again now with another pricey bundle of fluids and parts in the boot. If it fails again, I may ask them to pay for said.