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Old 12-04-2010, 10:55 PM   #1
Psycho71
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NP208c questions

Bought a 3/4 4x4 burb a while back. '85 model with a 350/400 208 drive train. Got the engine built, trans dropped off to be built, and today I broke into the transfer case to inspect it and replace the seals. Mechanically it looks fine. The seals are dry and hard, so I am glad I chose to look it over. I have the necessary seal kit, so they are all getting replaced. Just a question or two about this thing before I put it back together.

I can cycle the shift selector, turn the shafts by hand, and get it to engage into 2hi, neutral, and 4low. But it doesn't seem to be engaging in 4hi for some reason. 4hi acts just like 2hi does (1:1 ratio), but doesn't engage and turn the chain/front shaft. Is there something in the way this thing operates that will not allow this to happen on the bench? 4low gives me both shafts turning together at the lower 2.6:1 ratio, just like it should. All of the gears inside look good, no abnormal/excessive wear present.

Also, how much slack is acceptable in the chain. With the case split apart and the two main shafts not supported on each end, it seems like there's not much slack present. I can push the ends of the two shafts apart slightly and all the slack goes away. I'm assuming I need to check the slack thru the top fill hole when i get the case put back together?

I did notice "japan" on some of the bearings inside. Any concern with japanese bearings? I know Timken are usually best, right? The bearings are all in fine shape and tight. Should I just run it with the Jap bearings or spring for some USA made stuff?


Thanks for any advice y'all can offer. This is my first endeavor into the 4x4 world, and just want it all to be right before I put it back together.

Jay
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Old 12-06-2010, 02:03 AM   #2
Rede
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Re: NP208c questions

I had my 208 rebuild at a local shop and they told me that if you can lay the chain so its stacked and move it so one side over laps the other, then that's likely going to slip under load.

In my case, I shelled out 900 beans for a rebuild only to find out I had a pouched front hub.
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Old 12-06-2010, 03:52 PM   #3
OLDCHEV4X4
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Re: NP208c questions

Actually the Japanese make pretty good stuff. Its all the other Asian stuff that aint so good.
I wouldnt be afraid of them bearings.
Although, i always go out of my way to buy American.
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Old 12-06-2010, 04:28 PM   #4
Psycho71
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Re: NP208c questions

Thanks for the info guys. That's two of the three questions answered. Much appreciated.

Now I just need to know why I can't get this thing to engage 4hi sitting on the bench? Anyone got any ideas/answers?
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