How Free Spinning Should It Be?

[dpuckett]

I was swapping out airboxes the other day, and in the process, I checked the free wheeling of my turbo vs Mom's and her stock H1C with 250K on it spins a LOT freer than my PDR35 that I bought used, but has around 40K on it now. I have never shut it down hot; always let EGT drop to <300 before cutting the fuel (I threw that in for the newbies ). I spun both of them by hand (turn the end with my thumb and finger), and hers spun almost twice as long as mine did. And, mine seemed to have some drag to it. Nothing grating, but it feels like it has a brake inside it or something. Does it need rebuilt? Is it something I can do? (I can do a gov spring in stall, along with freeing a guide pin in the top of the VE pump. ) OR would it be better to ship it up north and have it redone? Or is that normal? Though I cant for the life of me figure out why it WOULD be normal; seems like beeing freer would make for faster spooling, higher boost, etc. I have a job in Loveland CO that requires me to use my pickup, (soon as I find a place to stay, which I am working on; have a guy to call Monday) and I want it up to snuff before I start working its a$$ off. I'm tempted to put the stock, worn out H1C on for a comparison, but that involves fixing my old intake hose. More work than I want to do right now



Daniel

 

[Forrest Nearing]

was her oil warm? was yours cold?



Forrest

 

[dpuckett]

Both trucks were cold, oil up to proper level, not that that makes a difference shut off. I realze oil temp would make a difference, but I wondered about the differences in the spinning, esp with most all else being equal.



I HAVE been in communication with CB Parker lately- maybe his jumpiness is rubbing off, 1400mi away.



-DP

 

[bgilbert]

Newbie question, (turn the end with my thumb and finger) do I do this with the truck running? LOL! Bill

 

[dpuckett]

Sure, You dont need the rest of your fingers, do ya?

To clarify for the smart butts here, I was referring to the nut on the end of the impellar end of the shaft. Geeezzzzz... ... ...

-DP

 

[sparks57]

FYI: if you want to pre-oil a fresh turbo turbo before running it, start the truck and hold the impeller... it will allow oil to move before the bearing rotates... trust me... I've seen it done.



My turbo was still spinning when I stopped my truck, then removed the air hose to check the filter a minute or so later. My wheel spins quite freely, but it also has an improved bearing in it.

 

[JLEONARD]

Daniel,

Start it up and let the oil pressure come up to make sure you get a shot to the turbo, then shut down and see how she spins.

As long as it doesn't have much play in it, and if it doesn't make any grinding sounds as it spins down after shut off, I wouldn't worry too much.

Jay

 

[1stgen4evr]

With the fingers

I think Bgilbert was suggesting that a new guy might make the mistake of touching the spinning impeller. I made a sugestion to a non mechanical guy that was incomplete and it ended up causing a problem. I try to think like a newbie when I post and may sometimes include something that seems simplistic but I would not want to be responsible for a problem.



Another suggestion on fooling around with turbos. Don't get the bright idea of putting your hand over the turbo when the motor IS running. The suction is considerable and might suck a finger into the blades. Since the dawn of the mechanical age, people have maimed themselves by just not thinking. Don't be an accident waiting to happen.



1stgen4evr

James

 

[sparks57]

Luckily, at idle, the suction isn't much. When I was researching the different methods to shut down an engine in the event of a runaway, I stuck my hand in from of my trubo and it killed my truck.



BUT: I would use a board if the truck was running away, because at that point, the suction would be rather great, and could cause personal injury. When that sucker's running over 100k rpm, it's a little scary!

 

[Forrest Nearing]

when the turbo is realy spinning, it'll suck your hand right in there!!! use a board!!!!

 

[Greenleaf]

OK, I'll go now and take my new modified turbo for a "test spin"... ..... 'cause it's STILL ON THE WORK BENCH!!!! (insert pouting/crying/nail biting face here).



Right back... ... ... ... ... ... ... ... ... .....

 

[Greenleaf]

Soooo... ... ??????

It spins free, but stops soon after letting go of it.



Felt a bit of radial shaft play, but no axial (in/out) play.



It's new and has zero hours (miles) on it.



Scott

 

[Forrest Nearing]

my turbo builder uses Lucas as assembly lube, so when I get them from him, they spin free, but stop soon after letting go...



but my HX40 will spin for a long time after shutting the engine down... and if I pop the hose and spin it by hand while the oil is warm, it'll spin for a long time.



Forrest

 

[paccool]

When I changed the exhaust housings on the old stock turbo, I couldn't get the old one off. I had another spool and intake housing I got from someone and used it instead of fighting the old exhaust housing off. It turned much harder than the old one but it didn't seem to make any difference as to how fast it spooled up or the boost pressure. Don't know if this relates to what you have or not but sounds along the same line.

 

[sparks57]

After I took the retaining plates off, I had to beat mine with a malet to get the exhaust housing off.



You did remember to remove the retaining plates... right Stan?

 

[paccool]

Hell, I beat on mine with a small sledge hammer and it still wouldn't come loose! Thats why I changed the spool piece.



Stan

 

[dpuckett]

Originally posted by paccool

Hell, I beat on mine with a small sledge hammer and it still wouldn't come loose!

Use a BIG sledge and some PB Blaster, and it'll come off. :-laf :-laf



-DP

 

[paccool]

Got the PDR HX35 on it now. The 16 housing was loose when it went on so I'm not going to worry about it anymore. Trust me, I really thought about a bigger hammer!

 

[Greenleaf]

Yep! Back when I changed out my housing on the 'ol H1 I gradually worked my way up to a full-blown sledge hammer. Left the retaining screws loose and she poped loose after a few hits from that sucker.



-S

 

[JLEONARD]

Guys,

I "hammered" mine apart based on knowledge from this forum... ...

However... . hammering took it's toll... ruined the turbo and I think the hammering did it. I'm convinced of that.

I recommend a more "gentle" persuasion techique... .....

Such as soft words, low volume jazz music, a glass of wine, and dinner at a nice restaurant works wonders... ... a "sexy " aftershave/cologne is critical to success. I use "diesel". (pm me for details)

Roses gets you guaranteed sex, as long as you BOTH have garlic during dinner.

Now, speak softly to your charger... turbo or otherwise... . mention things like .....

a new additive

gentle application of the throttle

a larger exhaust pipe (or an operation to "tighten" the outlet)

more fuel on request

flowers at the diesel stops

new antifreeze

new filters (only promise these if SEX is imminenet)

New shoes (if desperate)

New brakes ... . (only if she wants never ending sex)

Oh my gorshk... ... . I need to stop and take a trip "upstairs".

Talk to you after my nap!!!!!

E C Jay