NP231 Rebuild

#1
Figured this might add a little bit of tech for anyone tearing down their 231. First off, I was going to take pictures each step but it slipped my mind after the first couple bolts and I figured Ill just do it when I put it back together.

I found the FSM online and printed it out for tear down. I set up a shelf right next to the bench and labeled all parts and ordered them in the order I removed them.

http://www.lunghd.com/Downloads_and_Links/NP231.pdf

I am going to purchase a master rebuild kit and a new chain. I found these on Amazon for cheaper than most everywhere else. I have not ordered them yet but probably will by the end of the day.

http://www.amazon.com/gp/product/B0...rd_t=36701&pf_rd_p=1970559082&pf_rd_i=desktop

http://www.amazon.com/Alloy-USA-11650-Transfer-Chain/dp/B005BFY8I4/ref=pd_bxgy_auto_img_y

One issue I have is I bought the 231 with the SYE already and do not know what brand it is or if a seal for the SYE output is the same as the stock tailcone seal. Guess I will find out when the kit comes. Also the bolt on the SYE that looks like a fill plug (I never removed it except to try to reseal it) leaks so I have to find an o ring or something for that. There was slight scaring from the chain slapping the case but nothing to serious. I do have a question about all these small cracks that you can see in the pictures below. Is this anything to worry about or is this normal? Is my case about to spider crack everywhere and explode next time it takes a big shock load, or is this imperfection in the casting?

Tcase4_zpsg1nvfcgo.jpg
Tcase3_zpsrjhvfmju.jpg

Don't have my good vice bolted down yet... had to improvise. Beat the bearings out with my 3/4" sockets. Those big ol sockets are coming in really handy.



And my redneck parts washer. Purple power actually does a decent job cleaning it up. Going to throw some black engine enamel on it and then start the rebuild when parts come in.

 
#3
Nice work Ronnie, I need to eventually rebuild mine I guess. What are the symptoms of a stretched chain?
I heard it when I would let off the throttle when cruising at a decent speed, especially in 4 lo. It very well could of been something else but there was scaring on the case from the chain so I suspect it was the culprit.

Also anyone have any opinion or knowledge of the cracks in the case in the pictures I posted?
 
#6
I cant see the pics you posted.
I do have a question about all these small cracks that you can see in the pictures below. Is this anything to worry about or is this normal? Is my case about to spider crack everywhere and explode next time it takes a big shock load, or is this imperfection in the casting?

Tcase4_zpsg1nvfcgo.jpg
Tcase3_zpsrjhvfmju.jpg

looks like normal casting marks. what did they look like once to sprayed the oil off of it?
I don't know I threw it in that metal bin to soak and haven't taken it out yet. Will take a look tonight when I get home. I can throw the case halves in my truck and stop by the 4 wheel center after work one day.
 
#7
Ordered the crown rebuild kit ($100) and the Alloy USA chain ($66) which was 30-40 cheaper than most other chains. I read some reviews and people had no complaints, plus it has a 3 year warranty.
 
#8
If it is an advanced.adapers sye, the output seal is the following :
national #3946
I ordered one a few years back and fit perfectly
 
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