Help! - Rear brake cylinder bolt size needed!

Actually, it maybe a 1mm pitch. I found this link to another Suzkui forum:

www.suzuki-forums.com/suzuki-jimny-sierr...sami.html#post329011

...that has a link to a table that describes the pitches used for different bolts sizes, apparently used by Suzuki. Here is the link:

www.boltdepot.com/fastener-information/M...ic-Thread-Pitch.aspx

I could always go Titanium! www.pro-bolt.com/titanium-hex-head-m6-x-...mm.html#.URVgaR1ri5I

Pop the rubbers out and warm the alloy cylinder up with a blowlamp and they will come out easily.

If you have destroyed the heads you will have to grind new flats, or put a slot across them.

They may well be fine pitch.
Standard ISO pitch is 1.0 for a 6mm thread, the fine pitch is 0.75mm. The Japanese have always used pressure die-casting for alloys, with fine pitched bolts. (The alloy corrodes much quicker than the traditional British sand casting alloys, but the die-cast ones don't have dirty great holes in them)

Pop down your local fastener supplier and get a couple of each

facade wrote: Pop the rubbers out and warm the alloy cylinder up with a blowlamp and they will come out easily.

If you have destroyed the heads you will have to grind new flats, or put a slot across them.

They may well be fine pitch.
Standard ISO pitch is 1.0 for a 6mm thread, the fine pitch is 0.75mm. The Japanese have always used pressure die-casting for alloys, with fine pitched bolts. (The alloy corrodes much quicker than the traditional British sand casting alloys, but the die-cast ones don't have dirty great holes in them)

Pop down your local fastener supplier and get a couple of each

The bolts are knackered but its raining so have abandoned for the day. Freezing and hacked off.

The old man is coming over in the week with a Dremel so should be able to get them out. There is not enough room to get a drill behind the plate and get it square onto the head to drill them out.

If all else fails then I will blow lamp them as suggested, thanks for the tip.

You need a set of these:

www.machinemart.co.uk/shop/product/detai...-piece-bolt-grip-set

They are the tool you need for removing nuts or bolts that have rounded.

Then once you have got it out you can take it to compare to the ones in Halfords or to the fasteners to get replacements.

If they sheer however, you'll be buggered and will need new wheel cylinders -but they are not that expensive anyway. A motor factor may even stock the bolts if you have to get new cylinders. It's certainly not worth trying to drill the bolts out of cylinders for the cost of new cylinders.

Kirkynut

kirkynut wrote: You need a set of these:

www.machinemart.co.uk/shop/product/detai...-piece-bolt-grip-set

They are the tool you need for removing nuts or bolts that have rounded.

Then once you have got it out you can take it to compare to the ones in Halfords or to the fasteners to get replacements.

If they sheer however, you'll be buggered and will need new wheel cylinders -but they are not that expensive anyway. A motor factor may even stock the bolts if you have to get new cylinders. It's certainly not worth trying to drill the bolts out of cylinders for the cost of new cylinders.

Kirkynut

Thanks. I've got new cylinders anyway as I am going the whole hog and rebuilding the rear brakes. No messing around now :evil:

I know the size now so I will order some decent grade stainless bolts.

GuardianAngel wrote: I know the size now so I will order some decent grade stainless bolts.

They will seize rock solid into the alloy by the time that you have got the wheels back on. :ohmy:

Never use stainless into alloy without a good coat of an electrically isolating thread coating.

Cadmium plated or zinc passivate is more usual.