99 Spec Turbo Qs

BLKTOPTRVL · 04-04-2008, 09:20 AM

Asked on another forum - but got no answer. Does anyone here know the answer to these questions?

I went to see a low mileage set of 99 Turbos.

The seller was very cool and I would have bought them there on the spot but...

Neither of the pinwheels would freespin in the housings. The most freewheel I could get out of them was about 3/4 of a turn. I am not sure if this was normal in the 99s with the abraidable material in place?
On the secondary, as I turned the shaft by the nut, there was no lateral motion, however one of the vanes (just one) of the compressor wheel would scrape the abraidable material. That seemd to indicate to me that either the ab liner was somehow out of alignment, or the turbo had one vane that has a larger radius than the others and is therefore out of balance? Is this possible?

Anyone have any idea what might have been going on with this set of turbos?

albertomg · 04-04-2008, 09:41 AM

fwiw, I once tried to spin the primary and could not. I'm running 99 twins.

BLKTOPTRVL · 04-04-2008, 12:36 PM

Quote:

Originally Posted by albertomg

fwiw, I once tried to spin the primary and could not. I'm running 99 twins.

That's worth a lot. It is good to know that is not a unique situation.

Chadwick · 04-04-2008, 01:26 PM

The 99 twins use journal bearings so without oil there is lateral shaft play which could allow the compressor wheel to touch the abraded seal. Both my primary and secondary turn freely.

Dan

BLKTOPTRVL · 04-04-2008, 07:56 PM

Thanks also. This seems like a warning sign to me.

dudemaaan · 04-04-2008, 08:48 PM

i don't know about the 99 spec turbo's but most all turbos i've ever messed with including my stock twins and single turbo all spin freely

04-04-2008, 09:20 AM	#1
BLKTOPTRVL Rotary Fanatic Join Date: Feb 2008 Posts: 192 Rep Power: 18	99 Spec Turbo Qs Asked on another forum - but got no answer. Does anyone here know the answer to these questions? I went to see a low mileage set of 99 Turbos. The seller was very cool and I would have bought them there on the spot but... Neither of the pinwheels would freespin in the housings. The most freewheel I could get out of them was about 3/4 of a turn. I am not sure if this was normal in the 99s with the abraidable material in place? On the secondary, as I turned the shaft by the nut, there was no lateral motion, however one of the vanes (just one) of the compressor wheel would scrape the abraidable material. That seemd to indicate to me that either the ab liner was somehow out of alignment, or the turbo had one vane that has a larger radius than the others and is therefore out of balance? Is this possible? Anyone have any idea what might have been going on with this set of turbos? __________________ ...shoot a mother-humpin moose, eight days of the week...

04-04-2008, 01:26 PM	#4
Chadwick Rotary Fanatic Join Date: Feb 2008 Location: Smyrna, TN, USA Posts: 239 Rep Power: 18	The 99 twins use journal bearings so without oil there is lateral shaft play which could allow the compressor wheel to touch the abraded seal. Both my primary and secondary turn freely. Dan __________________ 93 RX7 BB (Race Car) 93 RX7 SSM (Soon to be IBM and a daily driver) 05 Silverado Z71 08 Mini Cooper 80 LS RX7 (for sale)

04-04-2008, 07:56 PM	#5
BLKTOPTRVL Rotary Fanatic Join Date: Feb 2008 Posts: 192 Rep Power: 18	Thanks also. This seems like a warning sign to me. __________________ ...shoot a mother-humpin moose, eight days of the week...

04-04-2008, 09:41 AM	#2
albertomg Rotary Fan in Training Join Date: Feb 2008 Location: Bay Area CA Posts: 91 Rep Power: 18	fwiw, I once tried to spin the primary and could not. I'm running 99 twins.

04-04-2008, 08:48 PM	#6
dudemaaan Rotary Fanatic Join Date: Mar 2008 Location: Brenham, TX Posts: 335 Rep Power: 18	i don't know about the 99 spec turbo's but most all turbos i've ever messed with including my stock twins and single turbo all spin freely