Question about the turbo on a Volvo 740 turbo

[wkilleffer]

Hello,
I contacted someone today who has a Volvo 740 turbo for sale. He said it needed plugs and plug wires to run its best, and that it sounded like the turbo needed some oil.

I don't know much about Volvo's, and the seller said he didn't either. Does the turbo use its own oil or does it get oil from the engine? I don't know much about how a turbo works, but it seems like this could be a sign of a dying turbo, and that I might ought to keep looking.

Any information or suggestions would be appreciated.

Thank you,

 

[Guest]

A turbo is basically the same as a supercharger, just that the compressor is driven by exhaust gases rather than the engine crank. The turbo gets it's oil from the engine crankcase, there is usually a feed line and return line from somewhere on the motor to the turbo and back again, making a circuit. The 850's have a chronic problem with leaking turbo oil return lines, don't know about the 740's. You can't just add oil to the turbo. If the motor has oil in it and the turbo isn't getting any then theres a problem somewhere. Thats another reason to make sure you're up on your oil changes. That oil not only lubes the turbo bearings but it cools them to a large degree also, so it's very important the oil is in good shape. If the turbo is dying that can be an expensive fix. Sometimes you'll see oil smoke in the exhaust, a sign the seals and bearings in the turbo housing are going. Worst case it completely dies and it stops pushing boost, you can check that with a gauge. I've heard of people driving the car for a long time with a dead turbo in it, don't know how good that is for the car though.

 

[kennypinkerton]

Turbo's routinely run close to or over 100,000 rpm. With a lack of oil feed, they'll need rebuilt real quick!

 

[JamesWilson]

[ QUOTE ]
...and that I might ought to keep looking.


[/ QUOTE ]

Probably the best policy where a potentially dodgy turbo is concerned....

They're a very nice addition to a car... but an expensive thing to fix....