Turbo ?

Discuss (and cuss) the Nissan LD-series OHC Six diesel engine, popularly available in the US in 1981-83 Datsun/Nissan Maxima Sedans & Wagons.

Moderators: plenzen, goglio704, glenlloyd, Nissan_Ranger

Post Reply
Shagbark
Posts: 27
Joined: 13 years ago
Location: Sallisaw, OK

Turbo ?

#1

Post by Shagbark » 12 years ago

How much play in the bearings would be considered normal? The one I pulled has some play in it but, I don't know if this is normal or not. I've driven and operated lots of turbo charged diesels (ranch manager for 10-years) but, we didn't work on them. When something wasn't running right, we sent it to the shop. The play I'm referring to is well, how do I explain this? OK, if you reach in the turbo from the ends, put your fingers on each end of the shaft, you can wobble it inside the housing. It doesn't have noticeable play if you push on it from one end to the other, only if you wobble it. The blades don't touch the housing but, they do get pretty close. Is this normal, or does it need bearings? I haven't taken it apart because, I wanted to ask someone about it first. Also , what type of seals do they have in them? Oh, I forgot, it spins without any noise but, I don't know how freely it is supposed to turn. If you spin it with your finger, how long should it keep spinning? Thanks for the help.

Frank
Frank

82 Maxima diesel wagon, AT, 139k miles (New daily driver).
85 720 pickup, AT, 235K miles, (Gasser, old daily driver).
85 F350 4x4, 185K miles (460 Gas Hog but, sometimes you gotta have some muscle).
2000 Firebird (Wife's car).

User avatar
kassim503
Posts: 1027
Joined: 14 years ago
Location: Stony Brook, NY

#2

Post by kassim503 » 12 years ago

I dont think that sounds right, I pulled and played with a turbo(s) on a Audi about a decade ago, I dont remember if there was play but if IIRC there was no play. I dont think there should be, those blades spin at 16k rpm and the bearings are ceramic rings, much like internal engine bearings, except with a layer of ceramic on it.
'83 maxima sedan, l24e, a/t, black

227K SOLD 6/7/2012

User avatar
asavage
Site Admin
Posts: 5346
Joined: 14 years ago
Location: Duvall, Wash.
Contact:

#3

Post by asavage » 12 years ago

I'm not an expert.

I will guess that I would be concerned with more than about, oh, .010" radial play (up and down), and probably a bit more than that axially. I have seen running turbos (Volvos and Cummins) with at least three times that amount still running.

They will run quite loose, and of course the seal won't be as effective with shaft play.

The seal is a ceramic cartridge, maybe. I don't recall.

The Garrett turbo can be fairly easily rebuilt at home, and there are eBay sellers (and others on the internet) that will sell you the parts. Under $100 for the shaft brgs and seal. Sometimes well under $100. Does not seem to require expensive setup equipment or jigs to do, though I have taken several apart I have never replaced those parts.

I am not an expert. Maybe someone else can research this?
Regards,
Al S.

1982 Maxima diesel wagon, 2nd & 4th owner, 165k miles, rusty & burgundy/grey. Purchased 1996, SOLD 16Feb10
1983 Maxima diesel wagon, 199k miles, rusty, light yellow/light brown. SOLD 14Jul07
1981 720 SD22 (scrapped 04Sep07)
1983 Sentra CD17, 255k, bought 06Jul08, gave it away 22Jun10.

odie
Posts: 114
Joined: 13 years ago
Location: CC, TX

#4

Post by odie » 12 years ago

If you can feel any play I would have it checked out further.
1996 VW Passat B4V TDI diesel...main ride
1983 Maxima LD28..sold
1984 Isuzu P'up diesel 4x4..sold
1981 Rabbit diesel - sold
1984 MB 190 diesel - for sale...sold
1987 MB 300TDT diesel...sold
1983 Holiday Rambler 6.2 diesel Banks turbo...sold
1983 Dodge Ram D50 2.3 TD diesel for sale
gas stuff-Jeep, Lebaron, Porsche, Harley

User avatar
kassim503
Posts: 1027
Joined: 14 years ago
Location: Stony Brook, NY

#5

Post by kassim503 » 12 years ago

oh, yea, ceramic seals is what I meant
'83 maxima sedan, l24e, a/t, black

227K SOLD 6/7/2012

User avatar
asavage
Site Admin
Posts: 5346
Joined: 14 years ago
Location: Duvall, Wash.
Contact:

#6

Post by asavage » 12 years ago

They spin a lot faster than 16k. A lot faster.

Noticeable play is not unusual, though also not optimum.
Regards,
Al S.

1982 Maxima diesel wagon, 2nd & 4th owner, 165k miles, rusty & burgundy/grey. Purchased 1996, SOLD 16Feb10
1983 Maxima diesel wagon, 199k miles, rusty, light yellow/light brown. SOLD 14Jul07
1981 720 SD22 (scrapped 04Sep07)
1983 Sentra CD17, 255k, bought 06Jul08, gave it away 22Jun10.

Shagbark
Posts: 27
Joined: 13 years ago
Location: Sallisaw, OK

#7

Post by Shagbark » 12 years ago

I sure appreciate you guys help. After further inspection of the turbo, I discovered that something had hit the compressor wheel. I don't know if the PO ran it without an air filter or just stuck a screwdriver in there to see if it would make sparks or what :roll: . The blades aren't broken but they are bent (not very bad). I think for most applications this turbo would just be a core. However, I think that I am going to straighten the blades, rebuild it and put it on the car just to see if the results are worth the expense of buying a good one. I'm not after HP, I'm after less smoke and better MPG. I'm not expecting miracles or anything but, if it doesn't give me at least a couple more MPG, then I don't see the point of having it. I'll just put my original parts back on the car and someone here will get a CHEAP($50, what I payed for it) 280ZX turbo set up. While I'm on the subject, I have a question. Well, first let me explain what I mean by "a couple more MPG". I bought this car primarily to drive on a meter reading route that I do on the side. This route is the ultimate test of stop and go fuel mileage. My 720 gasser got about 10-MPG on this route. My Maxima gets 18. My point to all this, is that this car only smokes (wastes fuel) under acceleration or if you pull a hill in too high a gear. I don't think a turbo will have much effect on fuel mileage cruising at highway speed on the interstate because the car is turning enough RPM to burn the fuel properly without a turbo anyway. This is speculation on my part and may be totally wrong. If this is correct however, then the turbo would be most useful as far as fuel mileage goes, mostly at low RPM under a load. So one would think that the faster it would create boost the better. I'm wondering if a smaller turbo (than a 280ZX) would be better for this application. Where your not trying to gain HP, your'e trying to gain MPG. Say, something that came off of a 2.2 litre engine or something like that. Would a smaller turbo create boost faster if you put it on a larger engine? What would a smaller turbo on a larger engine do at high RPM? Would it just spin faster than it did on the small engine? The darn thing may turn so fast that it comes apart or burns up :shock: .
Frank

82 Maxima diesel wagon, AT, 139k miles (New daily driver).
85 720 pickup, AT, 235K miles, (Gasser, old daily driver).
85 F350 4x4, 185K miles (460 Gas Hog but, sometimes you gotta have some muscle).
2000 Firebird (Wife's car).

User avatar
asavage
Site Admin
Posts: 5346
Joined: 14 years ago
Location: Duvall, Wash.
Contact:

#8

Post by asavage » 12 years ago

Shagbark wrote:After further inspection of the turbo, I discovered that something had hit the compressor wheel. I don't know if the PO ran it without an air filter or just stuck a screwdriver in there to see if it would make sparks or what :roll: . The blades aren't broken but they are bent (not very bad). I think for most applications this turbo would just be a core. However, I think that I am going to straighten the blades . . .
Don't. If the compressor vanes are bent, it's a parts core only. You cannot straighten the vanes equally and unequal will give significant turbulence (and unwanted heating) to the air charge.

But that's not why you don't want to use it.

If you bend a vane twice, it's likely to break off at the speeds it runs. A broken bit of vane will go right into your engine, and there it will stay. When a turbo's compressor overspeeds and breaks, it usually takes the whole top end of the engine with it.

That's why you don't want undersized turbos without wastegates, and why you should not attempt to run that turbo with the deformed compressor vanes.

Aside from that, if you read the LD28 turbo thread, you know that you really want the 300ZX turbo anyway.
Regards,
Al S.

1982 Maxima diesel wagon, 2nd & 4th owner, 165k miles, rusty & burgundy/grey. Purchased 1996, SOLD 16Feb10
1983 Maxima diesel wagon, 199k miles, rusty, light yellow/light brown. SOLD 14Jul07
1981 720 SD22 (scrapped 04Sep07)
1983 Sentra CD17, 255k, bought 06Jul08, gave it away 22Jun10.

HowlerMonkey
Posts: 130
Joined: 13 years ago
Location: West Palm Beach Florida

#9

Post by HowlerMonkey » 12 years ago

I've had a couple of turbos die and drove the car another 5k miles after disconnecting the oil line and loosening the two bolts that hold the oil return to the turbo so I could slide in a thin sheet of metal.

When I had the resources to do the job correctly, I found zero damage in the engine upon disassembly regardless of the fact that the compressor wheel was now a semi smooth ball.

Now a ball bearing turbo would have lunched the engine.

User avatar
asavage
Site Admin
Posts: 5346
Joined: 14 years ago
Location: Duvall, Wash.
Contact:

#10

Post by asavage » 12 years ago

HowlerMonkey wrote:I've had a couple of turbos die and drove the car another 5k miles . . . When I had the resources to do the job correctly, I found zero damage in the engine upon disassembly regardless of the fact that the compressor wheel was now a semi smooth ball.
That's incredible. As in "not credible".
Regards,
Al S.

1982 Maxima diesel wagon, 2nd & 4th owner, 165k miles, rusty & burgundy/grey. Purchased 1996, SOLD 16Feb10
1983 Maxima diesel wagon, 199k miles, rusty, light yellow/light brown. SOLD 14Jul07
1981 720 SD22 (scrapped 04Sep07)
1983 Sentra CD17, 255k, bought 06Jul08, gave it away 22Jun10.

odie
Posts: 114
Joined: 13 years ago
Location: CC, TX

#11

Post by odie » 12 years ago

I swapped a turbo on my Mercedes once...only because it was an incorrect CA smog turbo and the intake tube would not seal.

When I removed the old one one of the blades had a small 1/4 bend. But it still spun smoothly and the car ran fine with it on.

I sold it as a core to some guy in Germany. Why he wanted a CA emssions turbo with a bent blade I don't know.... :?:
1996 VW Passat B4V TDI diesel...main ride
1983 Maxima LD28..sold
1984 Isuzu P'up diesel 4x4..sold
1981 Rabbit diesel - sold
1984 MB 190 diesel - for sale...sold
1987 MB 300TDT diesel...sold
1983 Holiday Rambler 6.2 diesel Banks turbo...sold
1983 Dodge Ram D50 2.3 TD diesel for sale
gas stuff-Jeep, Lebaron, Porsche, Harley

User avatar
kassim503
Posts: 1027
Joined: 14 years ago
Location: Stony Brook, NY

#12

Post by kassim503 » 12 years ago

asavage wrote:
HowlerMonkey wrote:I've had a couple of turbos die and drove the car another 5k miles . . . When I had the resources to do the job correctly, I found zero damage in the engine upon disassembly regardless of the fact that the compressor wheel was now a semi smooth ball.
That's incredible. As in "not credible".
I had some audi from the 90's that kept chewing through turbos because of bad oil pressure, I never knew nor did I care, it wasnt my kind of car in the first place. It literally ate one turbo a month and then i wound up throwing it out some odd year later. I guess the motor was fine cause when the turbo worked, it ran rather well. But I had bearing and exhaust side compressor problems, the most I ever had was bent up intake blades
'83 maxima sedan, l24e, a/t, black

227K SOLD 6/7/2012

User avatar
asavage
Site Admin
Posts: 5346
Joined: 14 years ago
Location: Duvall, Wash.
Contact:

#13

Post by asavage » 12 years ago

kassim503 wrote:I had some audi from the 90's that kept chewing through turbos because of bad oil pressure . . . But I had bearing and exhaust side compressor problems, the most I ever had was bent up intake blades
Yup. It's common for a turbo to seize and stop turning, or the bearings have enough play that the turbine and/or compressor sections rub on the housing and it stops turning. However, that's entirely different than chunks of aluminum, some fairly large, coming off the compressor and going through the engine. I've been into enough of those top ends.
Regards,
Al S.

1982 Maxima diesel wagon, 2nd & 4th owner, 165k miles, rusty & burgundy/grey. Purchased 1996, SOLD 16Feb10
1983 Maxima diesel wagon, 199k miles, rusty, light yellow/light brown. SOLD 14Jul07
1981 720 SD22 (scrapped 04Sep07)
1983 Sentra CD17, 255k, bought 06Jul08, gave it away 22Jun10.

Shagbark
Posts: 27
Joined: 13 years ago
Location: Sallisaw, OK

#14

Post by Shagbark » 12 years ago

I'm glad you said that. I was remembering a turbo with bent blades that we had on a tractor. The guys at the shop had just straightened them and put it back on because a new turbo was going to cost so much money. What I hadn't recalled, was the reason the blades were bent. An injector tip had come off and went through the turbo. The blades that it bent were on the exhaust wheel, not the compressor wheel so, you could gamble a little with that. It would have dawned on me eventually but, now I don't have to wait or hear that darned theme music from the movie 2001 a Space Odyssey in my head :wink: . Thanks Al.
Frank

82 Maxima diesel wagon, AT, 139k miles (New daily driver).
85 720 pickup, AT, 235K miles, (Gasser, old daily driver).
85 F350 4x4, 185K miles (460 Gas Hog but, sometimes you gotta have some muscle).
2000 Firebird (Wife's car).

User avatar
asavage
Site Admin
Posts: 5346
Joined: 14 years ago
Location: Duvall, Wash.
Contact:

#15

Post by asavage » 12 years ago

Oh, sure, you can put all kinds of crap though the exhaust turbine, and no harm done (other than wasting the turbine wheel, of course).

But lose one bit of the compressor wheel, and it's goodbye top end. I don't have any pics, but I bet you could find some around somewhere.
Regards,
Al S.

1982 Maxima diesel wagon, 2nd & 4th owner, 165k miles, rusty & burgundy/grey. Purchased 1996, SOLD 16Feb10
1983 Maxima diesel wagon, 199k miles, rusty, light yellow/light brown. SOLD 14Jul07
1981 720 SD22 (scrapped 04Sep07)
1983 Sentra CD17, 255k, bought 06Jul08, gave it away 22Jun10.

Post Reply

Who is online

Users browsing this forum: No registered users and 1 guest