groznyiv

iTrader: (1)

Okay gentlemen,

I have a dilemma. I have a car show 200 miles away this weekend. I have an 89 vert with a TII swap. The engine has about 3K miles on it since the rebuild but the turbo was not rebuilt and has unknown mileage.

About a month ago it began to smoke. Compression is good, no hard start when hot or cold. I looked at my records and even though I had put only 1500 miles on it last year I had NOT changed the oil in that year. When I changed the oil, the old oil( castrol 10W30) was still somewhat yellow but was very thin and smelled of gas. I put castrol 20W50 in it and ran it for about 10 miles and the smoking went away.

Yesterday I took it in to a reputable rotary shop to have it looked at before the trip. When he checked the turbo for shaft play it had about an 1/8th to maybe a 1/4 play back a forth but not side to side. It did appear to have some slight rubbing on the housing. When I left the shop after about 2 hours it smoked for about 5 minutes and then quit.

Finally to my question. Should I drive it on a 400 mile trip or am I risking major damage if the turbo fails? What are the chances of it failing?
I drove it today and other than a little smoke after setting all night it ran fine and boosted fine. I would like to take it but it is not remotely necessary.

Thanks for the input.

David

SirCygnus

iTrader: (1)

i would drive it and try not to boost at all.

PvillKnight7

iTrader: (16)

Worn out internal engine seals. The engine needs to be rebuilt.

groznyiv

iTrader: (1)

I do not believe it is worn seals as it does not smoke when revved to 4K and held there for about a minute. The engine was rebuilt by a shop with a very good track record. The consensus is the turbo is beginning to fail and needs rebuilt.

RotaryRocket88

iTrader: (7)

Yes, it sounds like the turbo is in need of replacement/rebuild. Oil seepage past the carbon seal on the compressor side, or the piston ring on the turbine side will cause smoking. In/out play is bad, and any amount of contact with the housing can lead to pieces breaking off into your engine. Have you checked the compressor (and intercooler piping) or turbine sides for any oil? I'm in a similar boat right now with some light smoking at idle, which means my new turbo is going on sooner than planned.

groznyiv

iTrader: (1)

I checked the cold side piping and no oily film. It smokes very lightly at idle and sometimes not at all. I did not check the hot side but will assume that is where it is coming from due to the play in the shaft.

So RotaryRocket would you drive your car 400 miles round trip knowing the turbo is going bad?

Also, are you having your turbo rebuilt? What will you be running?

Thanks,
David

gorge

I have oil literally pouring out of my turbo. About 100ml/min.
Could I be in that boat, or is the oil flow too great and would it indicate that oil is coming from within the turbo?

groznyiv

iTrader: (1)

Does it smoke all the time or only at high rpm or when shifting at high rpm? Oil control seals can smoke at idle but this is rare. Usually if the oil control seals are bad you will first notice it when shifting at higher rpm and it will then smoke progressively more at lower rpm as they continue to degrade. A good test to tell if the oil seals are bad is to rev to about 4k after it is at operating temp then rev between 4kand 5k and if the smoke gets worse you have bad seals.

If it is smoking all the time regardless of rpm I would check the turbo shaft play and also what RotaryRocket88 said by pulling the intake and look for oil in the piping.

groznyiv

iTrader: (1)

RotaryRocket88 disregard the last two questions about which turbo you will be running. I just read your entire post and see you will be running a t04b v-trim.

RotaryRocket88

iTrader: (7)

Yeah, it's a hybrid I've put together using an old stock turbo from another engine. When I took it apart to rebuild it, I found a lot of carbon build up around the piston ring that seals the oil off from the turbine. It would not surprise me at all if that build up eventually prevented the piston ring from sealing properly. The ring itself and where it seated in the CHRA looked to be in good shape, but smoking may have been in its future if I had just slapped it on without rebuilding.

What exactly were the measurements the guy gave you for in/out play? inches? mm? And where was the wear on the housing? Inducer fins making contact?

groznyiv

iTrader: (1)

The shaft play was about 1/8th of an inch. The wear was being caused by the inducer fins. When I looked at it it did not look like the wear was significant, but he said it looked like it had been wearing on the housing for several hundred miles.

I do not hear any change in the way the turbo sounds when it spools but I am running a greedy power extreme and my hearing is most likely impaired.

groznyiv

iTrader: (1)

The shop wants me to replace the turbo with a borg warner brand turbo and then run a standalone haltech ecu. I am leaning towards a BNR stage 1 or 2 and the RTEK7 stage 2. Any thoughts on what would be a better way to go and keep costs down somewhat?

RotaryRocket88

iTrader: (7)

I'm not sure there's even an 1/8th inch of room for the compressor to move forward. The clearance between it and the housing is somewhere on the order of 1mm or less, and the turbine wheel/shaft has a similar amount of give before the wheel contacts the heatshield/CHRA. That's why there's supposed to be zero in/out play.

As far turbo/EMS upgrades, it depends on a lot of factors. How much power do you want? Do you want to preserve low-end torque/quick spool? Would you be tuning it, or would you be paying for someone else to do it?

groznyiv

iTrader: (1)

I called Brad back and he said it had about 0.5mm to 0.75mm play. I'm old and still think in SAE terms. So would you drive your car if it were in the same condition. I am leaning to not taking it but still going just to visit the family and see the cars.

As for what I am looking for hp wise. I would like about 300 hp that is not stressing the engine and still able to get in the 20s mpg on the highway. And, yes I would like to preserve the low end torque/quick spool. Coming from an NA, I want the low end torque. I put up with 13 years of gutless low end from my vert.

RotaryRocket88

iTrader: (7)

I guess I'd have to see the wear and how contact was being made to decide if it were worth driving or not.

As far as your power goals, it sounds like you're looking for the same thing I am. Useable torque on the street is what I'm after. There are some good threads in the Rtek section with info on tuning hybrid setups. It's pretty straightforward.

groznyiv

iTrader: (1)

Thanks for the info. I decided not to drive it to the show. I went and the car that won the division I would have been in was a 1982 corvette.

I will check out the Rtek section as that is the way I think will give me the most bang for my buck.