Knightsports RF420\'s - Think mine might be borked :(

[Matt_K]

I think mine have died.

I was accelerating though 6000rpm, 0.7bar when there was a bang. It sounded like a loud exhaust pop but much further towards the front. My exhaust suddenly sounded like it was blowing through a hole in the midpipe, and a screeching noise from the turbo on boost. Thought I\'d blown a gasket but the sound was too metallic, too noisy and quite worrying.

Got the car up on the axle stands today, to find not only a hole in my midpipe (Easily replaced) but also on visual inspection some very minor damage to the turbo blades, as well as more movement than I\'d expect when subjected to up/down/left/right motion. The rear turbo has minor play, nowhere near this much however.

No in/out play at all in either, so I was wondering if the excessive movement is because there is no oil pressure keeping the shaft central - or whether they are totally broken. I\'ll admit, I can rebuild a rotary engine, I know how a turbo works, but I don\'t know if mine is shafted or not. :xconfused

any thoughts? pics and vid to follow....



Video of the shaft play..
http://www.youtube.com/watch?v=w7CxeTBVzW8

[ashc]

thats more shaft play than my rf420s - when i got mine a rebuild was £768 -eek!!

[jamison1982]

might be wrong but i thought up and down minor play is ok but if side to side aswell, its not good.. too much play and will eat its self

[m1tch]

Hmm that does seen quite a bit of play, if the turbo has journel bearings (ie oil) a bit of play is ok, if they are BB bearings then it shouldn\'t have any. Is there any in or out movement?

[cyman]

can you get the blades to rub on the housings?? if you can then def need some bearings.  if they are journal bearings though you will get quite a bit of movement with out the oil pressure

[m1tch]

*ahem* BNR stage 3s *ahem*

[a.tapos]

Turbo play should be the same in all direction as (up and down left and right) it is alot but not knackered as it doesnt seem to have touched housing,possible rebuild,you may find the turbo failure is the hotside/exhaust side of the turbo so hard to see which may explain your hole,does it run as it might have thrown a tip?

[BlitzBoy]

*ahem* BNR stage 3s *ahem*

Over rated, from my own experiance mapping BNRs and Knighsports, the Knighsports own the BNRs hands down, Knightsports for the win.

[Matt_K]

Turbo play should be the same in all direction as (up and down left and right) it is alot but not knackered as it doesnt seem to have touched housing,possible rebuild,you may find the turbo failure is the hotside/exhaust side of the turbo so hard to see which may explain your hole,does it run as it might have thrown a tip?

Idle is solid so I doubt I\'ve thrown a tip. I\'ll have the turbo\'s out of the car tomorrow, whip the manifold off and check the block/manifold gaskets there too while I\'m at it.

[m1tch]

Could a turbine blade have let go?