NP203 removal and rebuild

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Chris64

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Just a tragic update, most everything is working fine although I now have some strange idling problem, but after sitting with transfer case full of oil, it has two small leaks.

This was why I took the thing out. Sigh.

Both places were places that used gaskets that came with a rebuild kit. Places that I RTV'd are fine (and the speedo output is fine). The two places are a cover plate that I think I can remove and reseal after draining. The other place is the rear facing cover that holds one of the main chain drives. This might be a nightmare if I tried to remove it. It seems like it's leaking from the lowest bolt that you normally use for draining the TC. I'm thinking maybe if I drain it I can just RTV this bolt and refill. Thoughts?
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Ricko1966

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It keeps the gap from opening and closing between the bottom of the engine and the bottom of the block. That gap at the bottom of the block where there is no bolts to the block or bell housing just the top half is bolted. That spot is like a hinge it can open up or pinch and bow up,cracking bell housing. I do not believe early trucks had the struts rods,I do not know what year they started
 

Chris64

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It keeps the gap from opening and closing between the bottom of the engine and the bottom of the block. That gap at the bottom of the block where there is no bolts to the block or bell housing just the top half is bolted. That spot is like a hinge it can open up or pinch and bow up,cracking bell housing. I do not believe early trucks had the struts rods,I do not know what year they started
I don't really understand what you're telling me. I know later transfer cases had supports, as this should too based on it's weight, but it bolts into a 1/2" thick iron plate so as long as I'm not jumping, it should be fine. Also, that isn't the source of the leaks.
 

Old Guy Bill

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It’s gonna be tough getting any type of seal with RTV etc.. with gear oil residue on the bolts or threaded holes.
Have to get them clean & dry
 

Ricko1966

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I don't really understand what you're telling me. I know later transfer cases had supports, as this should too based on it's weight, but it bolts into a 1/2" thick iron plate so as long as I'm not jumping, it should be fine. Also, that isn't the source of the leaks.
The problem was with frame flex. Off road the frame flexes and twists and cracks the bellhousing as the gap between the bottom off the bell housing and bottom of the opens and closes due to stress. That's what the strut rods are suppose to prevent. I wasn't commenting about your leak,I was joining the discussion of the strut rods. And you likely won't have a problem. But enough did that GM came up with a fix.
 
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Mr Clean

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I'm just starting to rebuild my NP203. From everything I have read, and all the YouTube videos... Did you put pipe sealant on the bolt threads when you reassembled it?
 

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