Broken Milner CV

[Paul_Humphreys]

CV must have been rubbish Rob. I run £50 CV from ebay and when I had 35" tyres I use to the with the front locked and on full lock. The CVs have been fitted for 2 years now.

Paul

 

[Ian Rubie]

Since you seem to like looking at broken bits of metal Rob here is the shaft of the last Milners CV that was in one of my cars. That let go at Lincomb to.

Ian

 

[Rob]

I have never seen anything fail quite like that, even in all my years at uni I have never seen an example like that Whilst your longfield shaft yielded then broke (ductlie fracture) which is a sign of a well designed part for shock loading, my instict is to say that the milners one above is far too brittle. But why the spiral fracture surface I have no idea

 

[Ian Rubie]

I have never seen anything fail quite like that, even in all my years at uni I have never seen an example like that

My speciality - I've never seen one broken like that

I still have the part as a keep sake if you want a closer look.

Cheers

Ian

 

[Rob]

I will have a look at it when I collect my CVs

 

[TonyP]

http://www.x-eng.co.uk/X-Shaft.asp

works surprisingly well- the magnet sticks like the proverbial to a blanket!

Looked that up today, but alas no stock

 

[Chris]

Tony - like I have said, the IFS half shaft has a snap ring on the end. This stops the end and intermediate sections from moving about. Solid shafts don't have that clip because they are not a sliding joint. So a magnet will pull the broken bit out. Basically the IFS drive shaft is in 3 sections. It's telescopic in simple terms. But to be telescopic, both ends have to be anchored. One is fastened through the hub, the other is clipped into the diff. Splitting this needs a pry bar. A magnet is NOT going to pull the broken section out against a snap ring especially when the surface is so jagged where contact is going to be minimal. Sorry buddy, there is no short cut here. As the surface IS so jagged, it might be possible to use something like liquid metal repair to bond a 'handle' onto it and pull it out. But it's going to take longer then popping the opposite shaft and poking it through from the other side, I'm afraid.

Chris

 

[TonyP]

Well you can't blame me for thinking about it. Anyway I like strong magnets... I have a small collection from hard drives

Yeah I recon it's going to end up being the hard way to replace my drive shaft. Parts first, then finding the spare time will be the next challenge

 

[Justin_Elliott]

Whilst your longfield shaft yielded then broke (ductlie fracture) which is a sign of a well designed part for shock loading, my instict is to say that the milners one above is far too brittle. But why the spiral fracture surface I have no idea

IMO it looks like its failed in torque as a brittle-shear failure... spiral pattern indicated a shear failure as max shear would occur at 45deg

But I agree with rob, as there are no signs of ductile yielding i'd suggest that the shaft was either a poor design, not been heat treated properly or the failure was secondary...

 

[Dave2000]

IMO the whole drive train including decent CV's should have no problem withstanding driving in circles on a hard surface fully locked at slow speeds. It won't feel nice and it will wear things out faster but nothing should break, IMO.

I agree, the fact that the centre difflock comes in as soon as you engage low range which I do to reverse a heavy trailer up a slope into a driveway, the road is tarmac and the drivetrain binds real bad but the CV's have not yet broken however, one is starting to click so I have ordered from Milners a replacement. I may be fitting the diff lock switch when I can find the right part number to take the load off.

regards

Dave

 

[Rob]

quote form lcool here

Toyota "Centre Diff Lock" switch (part number 84725-60040 on the new dashboard and 84725-60010 on the old).

the old dash has curved switches like this:

If you dont have any of these on your dash you need the newer one.

 

[Gav Peter]

I have yet to do this to mine.

Ecky did his "on the dark side" with some interesting results IIRC... ;-)

Where is he these days BTW? Don't recall seeing a post from him for yonks...

 

[Richard Jackaman]

I think that you need to add the switch then do some "pin mod" on the diff to be able to disable the centre diff in low range.

Just adding the switch allows you to engage the centre diff in high range only.

Cheers

 

[Dave2000]

I know we have wandered a little off topic sorry, but thanks for the info guys, I have the older dash Rob and have switches as per your pic. I am at the main stealers tommorow so I will get my order in.

Thanks again

regards

Dave

 

[Rob]

May I advise you speak with Ian Rubie on here, main dealer was £87 for me! Ian can get it considerably cheaper.

 

[Chas]

Just adding the switch allows you to engage the centre diff in high range only.
Cheers

Does that mean then that shifting into low range disengages centre diff? I thought it would stay engaged.
Chas

 

[Scott]

I think that you need to add the switch then do some "pin mod" on the diff to be able to disable the centre diff in low range.

Just adding the switch allows you to engage the centre diff in high range only.

Cheers

When you add the centre diff lock switch, don't bother with the pin mod, unplug a sensor on the transfer box and that'll stop the car knowing you've engaged low range. The sensor is around the 01:30 position (clock face view) on the transfer box. Now you'll have full control over when the centre diff lock is engaged in high or low range.

If your 80 has auto transmission this will also stop the auto box holding gear till 3000rpm when low range is engaged, it'll now change gear in the normal, more civilized shift pattern.

Sorry to stray off topic.

Cheers,

Scott.

 

[karl webster]

Regarding the switches lads try me or steff. ive sold quite a few and im sure steff has, and at a price of 87ponds for a switch id rarther leave it.

 

[Chris]

Indeed you have. And it works lovely Karl. I didn't bother with the pin 7 thing in the end. I got lost in all the contradictory explanations of what it did. I unplugged the transfer case connection, added the dash switch and now I have the same change pattern in high and low and can control all three diff locks in both high and low. So low with no centre diff! Cool.

Chris