how does an unbalanced torbo sound ?

[v8killer]

i just rebuilt my tdoh5 20g and the turbo wont build boost and makes a howling noise when it spools, i think the shaft could be bent. any advice ? the turbo spins great with very minimal play.

 

[94awdcoupe]

Howling usually means the wheels are hitting the housings. Thats why it wont build boost.

 

[ricktb]

I had a bent shaft in my evo 16g and it sounds nasty.. you can hear the turbo spooling rather loudly and have trouble building boost, could be described as a rough whining spool.. I had the turbine shaft tested for trueness and it was only bent by .01 of an inch but I guess they have to be within .0005.. thats 5 ten thousandths on an inch.. A turbo tech told me this.. One reason is because in a journal bearing turbo the turbine floats on a very thin film of oil and any bends might cause metal contact and will fatigue the components early..If you ever take it apart check the pieces for scratches or discoloration (heat)..

 

[Boosted98gsx]

Make sure you check for axial play (in and out) as well as radial play (side to side with respect to the compressor wheel). Axial play will result in a compressor wheel digging into a housing.

 

[Jeff99GS]

The sound goes like this.....ZZZZZZZZZZZZZZZZzzzzzz BOOM!

 

[tkelly27]

My big 16g had a custom clipping done by an exhuast valve. It was pretty out of balance, but it ran strong for a few thousand miles. I'm rebuilding it now, but just being out of balance may not do anything.

 

[v8killer]

well the compressor wheel is new and the wheels are not hitting the housings. the td05h exhaust wheel came out of a big 16g that had both wheels hit the housings. iguess i'll be ordering a new td05h exhaust wheel before it destroys my new compressor wheel !

 

[toofast82]

the td05h exhaust wheel came out of a big 16g that had both wheels hit the housings. iguess i'll be ordering a new td05h exhaust wheel before it destroys my new compressor wheel !

I would think if the turbine hit the housing, it is at least probably out of balance and could be bent. How worn was the actual shaft? Did you use oversize bearings or anything?
I have an old 18g where the compressor hit the housing and is chewed up some, but somehow it didn't do any damage to turbine blades. When I removed the shaft though, i could see it was grooved where the journal bearing was on it as well as the bearing being garbage.

 

[v8killer]

I would think if the turbine hit the housing, it is at least probably out of balance and could be bent. How worn was the actual shaft? Did you use oversize bearings or anything?
I have an old 18g where the compressor hit the housing and is chewed up some, but somehow it didn't do any damage to turbine blades. When I removed the shaft though, i could see it was grooved where the journal bearing was on it as well as the bearing being garbage/QUOTE]

no wear just barley hit the housing, i think it is bent i have rebuilt a few mhi turbos and have never heard that sound. my last 14b would make a real low howl in the mornings till i guess it warmed up then wouldn't do it the rest of the day.