Fitting A Diff

[Guest salty_monk]

Jim,

 

Yes please!!

Not at Donnington but have sent you an e-mail... Is Battery Bill anywhere near you??

 

Cheers,

 

Dan

 

P.s. is the diff going to need new oil seals (drive shafts) as I'll order some & get someone to pick them up for me if so... (along with the new half shaft bolts..

[Guest salty_monk]

Ok.. diff going back in tomorrow or Monday.

 

Questions:

 

Do I fit the half shaft bolts (4 per side where they go through the brake backplate & into the axle) with loctite or with copper grease?

 

Do I fit the propshaft bolts with loctite or with Copper grease?

 

Diff bolts have Nyolocs but I assume a bit of loctite on the blind bolts wouldn't go amiss??

 

Cheers!

[Big Jim]

If you're going to use locktight, only use "nutlock"

[Guest salty_monk]

Why's that then?? Where do I get it? Is it recommended or am I just as well to use some grease??

 

Cheers,

 

Dan

[Big Jim]

No don't use any lubricant, to be honest, i've never used additional locktight on this type of bolt, and never had a problem, i've just put them in "dry"

[Guest paul thompson]

I can tell you all a little story about lubricating threads.

When I used to work for a brake tube supplier, we had a problem with the Ford Engineer deciding that 8 Nm wasn't enough to tighten the brake tube nuts (been that way fro 20 years no problems) Then he decides to release 12Nm to tighten the nust as that was on his little chart of torques allowed cause of the tooling to do them up with. What he forgot was that a year before, the prvious engineer released lubricated nuts! The combination of lubricant and higher torque meant they flattened the flare on the tube such that it didn't seal, or occasionally they kept turning the thing without reaching the torque. What happens when you lubricate the thread is the clamping load applied is increased by about 30% for the same torque. Unless you lubricate under the head, it doesn't come undone any easier (except once you have slakened it off) because the clamp force is now so high. If you use a loctite patch bolt then you need 20% more torque to achieve the same clamp load. I hope that makes sense. By the way, none of the bolts for the rear uprights had loctite patches on, so I wouldn't bother, use a spring washer instead.

[Guest salty_monk]

Thanks all, Diff went back in tonight & the noise has now all but vanished

 

What a performance for want of a bit of oil!!

 

Paul, don't really understand your theory, why should the grease affect the torque? Is it because it slides so much easier that you then have to do the bolt up tighter to get the same reading at the torque wrench?

 

Hope to see all the Kent boys on Friday..

[Peter Bell]

If the thread is unlubricated a lot of the tightening force is used up by friction in the assembly. When it is lubricated the friction reduces dramatically so the force tightens the thread as opposed to just overcoming the friction.

Peter