Richard Macfarlane

[richardmac12345]

I am putting a outer boot on a skoda Fabia 1 outer cv joint.

I am trying to undo the inner cv bolts and I think they are a M10 triple square. I don't have this key but

have some spline bits which look similar. Am I correct that the inner bolts are m10 triple square and what is the difference between that and a spline bit? can I use a spine bit?

 

I also find that the is little room to undo the bolts.

 

can anyone done this job with basic tools and can they advise on these matters.

 

thanks

 

richard.

[Breezy_Pete]

Either M10 or M8, depending on engine type, I think.

Triple square has 90 degree points, spline are 60 degree (4 triangles rather than 3 squares.

Will fit and probably work OK, biut be extra-careful that they go all the way into the screw heads (hammer on end of extensions til you feel it bottom out).

 

Yes, access is awkward. Keep turning the driveshaft to get each screw into most accessible position as you go.

[Carlston]

1 hour ago, Breezy_Pete said:

Either M10 or M8, depending on engine type, I think.

Triple square has 90 degree points, spline are 60 degree (4 triangles rather than 3 squares.

Will fit and probably work OK, but be extra-careful that they go all the way into the screw heads (hammer on end of extensions til you feel it bottom out).

 

Yes, access is awkward. Keep turning the driveshaft to get each screw into most accessible position as you go.

 

The terms XZN, spline, and triple square are all used interchangeably.

 

I've never seen 4 triangles with 60 degree points, on either XZN or spline tools.

 

Here's one example of a 40 piece set that comes with ten spline tools with both long and short versions of M5, M6, M8, M10, M12. The spline tools in these sets are triple square, not 4 triangles as I've checked the largest M12 size using a magnifying glass.

 

"40 piece torx spline hex bit set"

https://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=p2334524.m570.l1313&_nkw=40+piece+torx+spline+bit+set&_sacat=0&LH_TitleDesc=0&_odkw=40+piece+spline+torx+hex+set&_osacat=0&_sop=15

 

These are common Chinese made sets rebranded under many different names. Even "Draper Expert" and "Britool Hallmark" rebrand them, but I doubt the quality of these is any different from the cheapest £10 versions.

 

Edited 6 August, 2023 by Carlston

[Breezy_Pete]

It's XZN, not XYN, which is triple-square, dunno what it stands for.

 

 

 

 

"I've never seen 4 triangles with 60 degree points", you say, so I guess that means they don't exist?

Edited 6 August, 2023 by Breezy_Pete

[Carlston]

16 minutes ago, Breezy_Pete said:

It's XZN, not XYN, which is triple-square, dunno what it stands for.

 

 

 

 

"I've never seen 4 triangles with 60 degree points", you say, so I guess that means they don't exist?

 

They may exist, but spline is normally used interchangeably with XZN.

 

I doubt you will find 4 triangles on VAG cars.

 

There's also "Ribe" but that's very different to XZN/spline, and I doubt Ribe is used on VAG cars...maybe some Italian cars.

 

Ribe

 

Edited 6 August, 2023 by Carlston

[Breezy_Pete]

I agree on your last point (and the edit about Ribe) and yes, the terms are often muddled. Perhaps I should have checked with the OP exactly what his 'spline' bit looked like, but the advice about ensuring full engagement is never wasted words.

Edited 6 August, 2023 by Breezy_Pete

[Carlston]

9 minutes ago, Breezy_Pete said:

I agree on your last point. and yes, the terms are often muddled. Perhaps I should have checked with the OP exactly what his 'spline' bit looked like, but the advice about ensuring full engagement is never wasted words.

 

It's looks like the bolts that the OP wants to undo have a tensile strength of 12.9 which is far stronger than the 8.8 tensile strength that wheel bolts are often made out of.

 

The 12.9 tensile strength should help to prevent the bolt head shearing if its very tight, but yes, full engagement can prevent a lot of unnecessary problems.

[richardmac12345]

I've removed five the bolts from the inner cv joint but the spline wont go into the bolt.

I've tried cleaning it. I think I will have to drill it out. Has anyone else had this problem?

thanks

[Carlston]

31 minutes ago, richardmac12345 said:

I've removed five the bolts from the inner cv joint but the spline wont go into the bolt.

I've tried cleaning it. I think I will have to drill it out. Has anyone else had this problem?

thanks

 

What size is the XZN? M8 or M10?

 

It's an M8 bolt, so I expect it is XZN M8.

 

Is the length of the bolt 48mm? (measured from under the head) 

 

Edited 6 August, 2023 by Carlston

[richardmac12345]

3 minutes ago, Carlston said:

 

What size is the XZN? M8 or M10?

 

It's an M8 bolt, so I expect it is XZN M8

 

The five i removed i used a M8 spline bit but can't get it into the last bolt.  It must be the same sise but i havn't damaged it. 

[Carlston]

53 minutes ago, richardmac12345 said:

The five i removed i used a M8 spline bit but can't get it into the last bolt.  It must be the same sise but i havn't damaged it. 

 

Maybe there is a tiny burr on the M8 splined bolt head.

 

Maybe you could use a big HSS drill bit, perhaps 10mm to 12mm in diameter.

 

These bolts are made out of 12.9 tensile strength steel, so it will quickly take the edge off the drill bit.

 

Try removing the smallest amount of material that you can. You are only trying to enable the M8 XZN bit to be inserted.

 

It might be better and easier to try modifying a M8 XZN bit, by giving it an ever so slight taper.

 

Edited 6 August, 2023 by Carlston

[sepulchrave]

Balls to all that, just tappy-tap-tap the bit into the head until it fits well enough to undo.

[J.R.]

AKA make it ave it!

[richardmac12345]

6 hours ago, Carlston said:

 

The terms XZN, spline, and triple square are all used interchangeably.

 

I've never seen 4 triangles with 60 degree points, on either XZN or spline tools.

 

Here's one example of a 40 piece set that comes with ten spline tools with both long and short versions of M5, M6, M8, M10, M12. The spline tools in these sets are triple square, not 4 triangles as I've checked the largest M12 size using a magnifying glass.

 

"40 piece torx spline hex bit set"

https://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=p2334524.m570.l1313&_nkw=40+piece+torx+spline+bit+set&_sacat=0&LH_TitleDesc=0&_odkw=40+piece+spline+torx+hex+set&_osacat=0&_sop=15

 

These are common Chinese made sets rebranded under many different names. Even "Draper Expert" and "Britool Hallmark" rebrand them, but I doubt the quality of these is any different from the cheapest £10 versions.

 

I bought a kit like that.

[richardmac12345]

13 hours ago, sepulchrave said:

Balls to all that, just tappy-tap-tap the bit into the head until it fits well enough to undo.

I might damage the spline bit and i haven't got another one.

[Breezy_Pete]

Whereabouts are you? 

 

 

[richardmac12345]

4 hours ago, Breezy_Pete said:

Whereabouts are you? 

 

 

welwyn garden city herts.

[Breezy_Pete]

You can't be far from a place to purchase a second tool from then. I think Sep is right, chances are a previous visitation to that screw has damaged the head a little (probably by under-engagement of the tool), and now it just needs some help with some force. 

A well lit close-up photo of the screw head may help everyone understand the situation, though I realise that's easier said than done.

 

Do you have replacement screws? Technically they are supposed to be single use. Stick your VIN in a message, or here if you'd like me to find part number.

[sepulchrave]

3 hours ago, richardmac12345 said:

welwyn garden city herts.

 

Amazon deliver VERY quickly where you are.

 

You could've had the correct tool to hand by now...

[Carlston]

If you need a spare XZN M8 so that you can use very gentle taps with a copper headed hammer, something like this might help. The tool is likely to be damaged in the process, and it's not guaranteed to work. However, I would try a high quality countersink tool first that's made for countersinking metal.

 

Perhaps take a close-up photo of the bolt head first like Pete sugggested, so that we can see exactly what the problem is.

 

XZN M8 x 75mm bit (£3.11 including shipping)

https://www.ebay.co.uk/itm/325759278794

 

Edited 7 August, 2023 by Carlston

[richardmac12345]

I have a spline one like that and tried to tap it in but i could could not get to it and so I'm drilling it out with a hand drill.

It is taking a while to drill it out although i have bought a new carbonite drill bit.

[Carlston]

1 hour ago, richardmac12345 said:

I have a spline one like that and tried to tap it in but i could could not get to it and so I'm drilling it out with a hand drill.

It is taking a while to drill it out although i have bought a new carbonite drill bit.

 

When you've taken a small amount of metal off, perhaps you could retry to see if the M8 XZN tool will go in.

[richardmac12345]

6 hours ago, Carlston said:

 

When you've taken a small amount of metal off, perhaps you could retry to see if the M8 XZN tool will go in.

I had tried to fit it after drilling for a while and so i then tried to tap the M8 bit in but could not reach over and tap in in. I therefore decided just to drill it out. I'm using a new 10mm Cobalt drill bit with engine oil and put the drill to the slowest speed. I can't see any swath coming off. can it be done with the drill i'm using?

[sepulchrave]

3 hours ago, richardmac12345 said:

I had tried to fit it after drilling for a while and so i then tried to tap the M8 bit in but could not reach over and tap in in. I therefore decided just to drill it out. I'm using a new 10mm Cobalt drill bit with engine oil and put the drill to the slowest speed. I can't see any swath coming off. can it be done with the drill i'm using?

 

No.

 

You simply won't be able to drill it out by hand because you cannot consistently apply enough force to the workpiece.

 

Your only hope now is to slice the head completely off the bolt using an angle grinder, then you can remove the driveshaft, remove the bolt stub using grips and refit using a new bolt.

[richardmac12345]

I'm trying to remove the drivers side drive shaft off my Skoda Fabia 1. I have removed five cv flange bolts and the sixth one i have drilled the head off using a 8mm drill bit and so there is a bolt stub that i will remove later. I have removed the outer shaft ball joint but the drive shaft won't pull off the final drive. The inner cv joint to the final drive doesn't move at all and there should be some movement. I did drill the stub bolt a little bit move to be sure i could pull the shaft off the final drive. I don't think the stub bolt is the problem as there is no movement at all.