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CV joint grease nipple

Ian Rubie

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I remember reading a while back on IH8MUD about a mod to a CV joint. Basically it involved drilling a hole through the centre of the shaft and fitting a recessed grease nipple. The idea being you can simply remove the hub cap and pump fresh grease directly into the part of the CV where it is needed.

What do you guys think, good idea or bad? Will a small hole (bigger where the nipple is recessed) reduce the strength? From my understanding, and after asking a few people with far more knowledge about metal than me, it will have a minmal effect.

I realise it is a machine shop job to drill the hole and will not be laying into a brand new CV with my Black and Decker.

Cheers

Ian
 
can't see a small hole making a great deal of differance to strength, you'll only be removing a very small % of material. You'll have to take the cage & balls out, to keep swarf off them and probably so the hole can be bored from both ends otherwise it will be a job to stop a small drill snapping even going at it carefully.
 
I recall the thread too - it is certainly a specialist job! I wonder about using some kind of cooling fluid sprayed onto the drill contact area to avoid too much heat increase and work hardening the CV? Not so easy to get it to the point of cotnact though...

This is the thread I think :idea:

Was your (broken) CV a little dry when you removed it?

Cheers,
 
the only problem i could see that this mod will introduce is a stress concentration around the hole and any defect in the material no matter how small (almost inevitable) is a perfect place for a fatigue fracture to propagate from.
 
Getting coolant along the drill isn't usually a problem as long as you withdraw the drill regularly to stop it clogging and the coolant will lubricate the drill sides a bit to stop it binding but depending on just how small the hole is it could be a slow job I think but then again I'm usually drilling big holes :mrgreen: After drilling it you could send it for cryo treatment to finish the job off?
 
Sorry I did not see the link Andrew posted, and after looking at the mod I can say that it will have minimal effect on the strength of the CV. So my previous post is irrelevant.
 
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We have chatted about this Ian. I think that it's a neat idea - which whilst cool possibly hasn't that much need in reality. I still think that a periodic strip down is necessary not just to regrease but to monitor condition. I think that this means that topping up is now possible but it doesn't negate the other aspects involved. Just being objective. I don't think that it would weaken the cv either the strength is really in the outer metal. But if there was a set available I'd buy them!

Chris
 
Thanks for the feedback. Now I know it was the Longfield shaft that snapped and not the Longfield CV giving up I am not sure what to replace it with.

Shall I go OEM CV & shaft or another set of Longfields? The Longfields have been in a few years but were starting to click badly. Will cryo treated OEMs stand up to the abuse I give my car as well as the Longfields have??
 
Cryo'd OEM isn't going to be any cheaper than Longfields is it? Can't see cryo'd OEM being close to being as strong as Longfields. Have you checked the unbroken side for twisting? They may have failed over a period of time?
 
Jon Wildsmith said:
Cryo'd OEM isn't going to be any cheaper than Longfields is it? Can't see cryo'd OEM being close to being as strong as Longfields. Have you checked the unbroken side for twisting? They may have failed over a period of time?

You are correct on price, Longfields are a bit cheaper. I have not pulled the other side yet, that is tomorrow evenings job.

Ian
 
There is a firm in Aus selling greasable CVs to the mining industry along with rubber gaiters to go between the steering knuckle and axle to keep the crap away from the wiper seals.

I customer appeared with a set which we fitted, but I can't remember the costs off hand.
 
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