NP242 and SYE.....oh my!

Man was I twitched! Now I'm just confused.

I have a 90 XJ ltd with np242 tcase.

I bought a 2nd np242 and the RE SYE. opened the case, took out the shaft and had it cut down and drilled for the SYE. went to put the RE flange on and it won't go on, even with some persuasion. WTF???

Then today I'm reading up on (did a search and wasted a couple of work hours reading) about spline counts, etc. Quickly ran home to make sure the flange and shaft have same spline count and they do - 27 each.

But now, why won't the flange go on? is it THAT tight of a fit? The shop that cut down the shaft did bevel them a bit, I figured that would line them up but they really don't seem to want to mesh at all. any hints/suggestions? Maybe a bigger hammer?

Trying sticking the shaft in the freezer for a couple hours, and heating the flange in the oven, or lightly hit it around the mating surface with a torch.

Then try the fit.

some splined things on cars have to go on in a certain spot or it wont work. try moving one spline over at a time all the way around to see if maybe your just in the wrong spot

I would agree with Neko. on this one, I've put sleeves in a chevy smallblock like this. Also if you have access to a deep freeze use it. However, I wouldnt reccomend the torch, it could screw up the heat treating of the shaft and or flange

Thanks guys, i'll try the freezer thing.

I definately wouldn't apply a lot of heat with a torch.. But lightly feathering it around the splines on the flange will help it expand some..

If you don't feel good about doing it that way, heat your oven to 350 and stick it in there for 3-5 minutes.

I had a moFo of a time too, it took a while with a small file to take the burr off where I made my cut and it was still very tight. The freezer /oven should work fine, My kids thought I was nuts, putting my rear axleshaft in the deep freeze and the bearing in the oven.

just had a thought --- the flange has to go on after the whole thing is assembled. If I put the shaft in the freezer it will be warmed up to room temp by the time its all reassembled and ready to put the flange on.....

I'll give it a shot anyway and see if I can at least get it on right out of the freezer - at least that way I will KNOW that it can go on.

Sounds like it's burred between the splines, maybe a small/fine file if it'll fit between and get all the way into the valley between the splines.

Got it! - took the dremel with a thin cutting disc and lightly ran it between all the splines right at the end of the shaft. still a very snug fit which I suppose is a good thing.

Good work!

Probably had some slag built up in there from cutting it that was screwing you over.

Good to hear, now get that case on!