Bolt size.

[dorkins]

Does anybody happen to know the thread size on the large bolts that hold the engine under tray in place on a 1999 ducato chassis, the bolts are m10's I believe but cannot identify the thread, I assume metric fine or extra fine, there are a couple of m6 fixed bolts that take just the nut but its the bigguns I need.

THANKS.

 

[Figaro]

At 23 years old, I'm surprised it still has an undertray.
They usually get damaged and drop off

 

[Stealaway]

Why do think they are not standard thread size?
Metric fine is rare and usually only brake callipers
Metric Extra fine is very rare

 

[pappajohn]

Have you tried a bog standard M10 ?

 

[dorkins]

At 23 years old, I'm surprised it still has an undertray.
They usually get damaged and drop off

its a new one, it still had a belt cover but that's getting a bit ropey so decided to replace the whole thing.

Why do think they are not standard thread size?
Metric fine is rare and usually only brake callipers
Metric Extra fine is very rare

To be honest, going by a local stockists who said they couldn't match the sample bolt I had.

^{_{Subscribers  do not see these advertisements}}

 

[dorkins]

Have you tried a bog standard M10 ?

I have but the thread appears to be too coarse, so thought it would be a relatively easy exercise to get the existing bolt matched (only got two) now seems to be a bigger problem than it should be! will try another stockist tomorrow but hoped somebody may know exactly, tried the local Fiat dealer but the "parts person" didn't know the thread "we only fit the bolts" so asked the question "do you have the bolts" but as the reg. came up as "out of production" the answer was "no", can't be asked to drive 10 miles to the dealer to see if they can match them! (might have to eat my words)

 

[Landy Andy]

Metric fine on mine.

 

[jockaneezer]

Sounds like they might be M10 x 1.25 pitch ?

 

[pappajohn]

Strange threads.....
I lost a bolt from the rear brake caliper on my car.....a simple M10.
Went through my considerable stock of nuts and bolts.
Like you, none with a fine enough thread.
Had to bite the bullet and order one from the local Hyundai dealer.
£1.80 for one scratty bolt.

 

[rod_vw]

Do you really mean M10 Screw/bolt, i.e. needs a 17mm spanner?

Or do you mean a bolt which needs a 10mm spanner?

You may find this link useful https://www.engineersedge.com/hardware/british-iso-thread.htm

^{_{Subscribers  do not see these advertisements}}

 

[Landy Andy]

Yes. M10X1.25, and requiring a 17mm spanner.

 

[dorkins]

Thanks all, I am hoping/confident that the stockist I am going to tomorrow will identify and hopefully have in stock this bolt, at least if I know for sure what it is I can then source it, probably turn out to be something bog standard!

Do you really mean M10 Screw/bolt, i.e. needs a 17mm spanner?

Or do you mean a bolt which needs a 10mm spanner?

You may find this link useful https://www.engineersedge.com/hardware/british-iso-thread.htm

it is an m10 bolt, 17mm hex head, seems well over the top for the job it does. My dad was an aircraft design engineer, he would have run his finger nail around the thread and told me exactly what it is! tried to teach me and I did learn a lot but engineering was not my world.

When I do find out I will post back here and let you know.

 

[dorkins]

Yes. M10X1.25, and requiring a 17mm spanner.

Thanks that could be a great help

 

[dorkins]

and the prize goes to....................Landy Andy! spot on, the bolts are indeed M10 x1.25x 25mm

thanks to all

 

[Landy Andy]

and the prize goes to....................Landy Andy! spot on, the bolts are indeed M10 x1.25x 25mm

thanks to all

Thank you.

It’s an oddly large size for its job, and I can’t see any reason why they use fine thread instead of standard. But pleased to help

^{_{Subscribers  do not see these advertisements}}