Turbo Life

[Red Herring]

Hi Fellas,

What, if any, is the life expectancy of the turbo unit on the 12HT motor?

I know it depends on maintenance, but assuning maintenance has been regularly done? Any ideas?

 

[denis]

my friend is having his rebuilt as a preventive measure. The unit has 350,000 or so kms.

 

[Radd Cruisers]

I guess the typical old story, was the engine idled down for a couple minutes before shutdown throughout its life?

You should not be able to feel any end play by hand, most have some due to wear.

How much is to much end play or bearing wear, you could use a dial base and indicator and check the FSM specs.

The rebuild kits are way over priced for a couple tiny seals and a bushing which they call a bearing. Although locally I have found no other source for these kits, might find something cheaper out of Austrailia.

Should have a couple of tools such as michrometer to measure shaft wear.

Many people think they should be rebuilt by a turbo shop and not left to a first timer?

Hey Steve, you just missed David and his friend who traveled through Victoria on Sunday in thier jap spec HJ60.

Drop by if your ever in Nanaimo, really dig those JDMs.


Rob

 

[crushers]

Rob,
actually that isn't quite true, even brand new turbos have play. the bearings ride on a cushion of oil and if there is no play then there would be no room for the oil...
the movement from side to side should not allow for contact with the housing.
cheers

 

[Radd Cruisers]

Rob,
actually that isn't quite true, even brand new turbos have play. the bearings ride on a cushion of oil and if there is no play then there would be no room for the oil...
the movement from side to side should not allow for contact with the housing.
cheers

Yes I agree there is a tolerance, what I was told is it should be very hard to detect by finger. If you feel a good deal of movement it is likely the bearing is out of spec.


I was in a diesel off road shop today and being the nosey guy I am reached in and tried turning the 6.5 turbo, barely could get it to turn.

The owner made a joke about spraying some WD-40 in thier to loosen it up.

 

[crushers]

i have a brand new one sitting here and there is easy movement. i asked the reputabe shop here in town about that and they brought our 4 different brand new turbos and they all had easy movement to prove their point to me...
interesting, maybe the NA turbos had tighter tolerances.
not trying to knock you in any way, just what i have seen and have been informed...
cheers

 

[cruiser_guy]

Turbo's I've seen spin VERY easily. I'd be concerned if it was tough to turn. I expect that the shaft would be hotter than the housing and therefore the shaft would expand more (get a larger OD) than the housing would when running. If it's already tight that would just make things worse.
Another way to look at it is when a turbo fails due to oil coking the bearings that makes the clearances smaller. I'd steer clear of turbo's that won't turn easily.
Having said all that though, there still better not be any axial play though a little play parallel to the shaft is OK.

 

[crushers]

axial- in/out play?

 

[cruiser_guy]

Poor terminology on my part. Play perpendicular to the shaft BAD, SLIGHT play parallel to the shaft OK.

 

[crushers]

play forward and back bad, play side to side is acceptable because of the clearences for oiling the bearing...
your teminology was fine, my mind could not get around axial...my bad.
cheers

 

[Red Herring]

And so... the life expectancy is....? Mine is working fine... just wondering.

 

[crushers]

anywhere from 100,000 to 500,000... very hard to say...
i have seen turbos with over 300,000 on them and still running fine...

 

[Miamirex]

Those AR turbos on Mercedes easily last 400K miles

 

[onefsatchevy]

How much are the rebuild kits? Generally speaking of course. And is it something that an amature mechanic could do??

 

[mac]

Holy thread resurrection! Close to 3 years? At least no one can accuse you of reposting.

I've seen a turbo on an OM617 Mercedes engine with 650K kms with an original turbo and interestingly they are only oil cooled w/ no water provision.

A shop rebuild can run you $500- $1000 easily.

 

[cruiser_guy]

Since we're talking about turbo rebuilds, what is the consensus on dynamic balancing after the rebuild and how much of a concern are some slight cracks in the exhaust housing (they do not appear to go through the housing)?

I've got an MR2 turbo that will be going on the FJ45LV/3B rebuild. I have rebuilt it and the bearings feel good but I don't want it to come apart at 100,000rpms and get swallowed up in the engine.

 

[mac]

My opinion is not expert but I've been told that for most turbo applications dynamic balancing is not nescessary. Compressor wheels are already balanced to a degree. I think it would be more critical on turbos that you find on big rigs with a larger rotating mass. That and maybe higher boost/performance applications.

As for cracks- a lot of housings have them. As long as they don't open up with heat I wouldn't worry about it.

 

[Tapage]

I've got an MR2 turbo that will be going on the FJ45LV/3B rebuild.

Are you compared the AR and trim of these MR2 Turbo with a 3B or 1HD-T CT26 .. ?

 

[cruiser_guy]

Are you compared the AR and trip of these MR2 Turbo with a 3B or 1HD-T CT26 .. ?

I'm not exactly sure what you mean. Turbo's for the 3B or 1HD-T are much harder to find. The inlet is slightly differently shaped than the 13B-T manifold but we should be able to make up a spool peice.

The 13B-T has a round outlet and the MR2 inlet is two oblong openings.

 

[brownbear]

an imbalance on a high speed compressor will feel like a buzz. So I would have some one pulling some boost with it and feel around the engine for a buzz sensation.

Otherwise the only way the turbo can fail is for the vibration to wear out the bushing causing the blades to contact the housing.

Keep an eye on it for awhile. Say once a month pull the intake on the turbo and feel for slop(radial). Then after your comfortable once on oil changes.