Front calipers: washers and safety wiring

[skelteanema]

Hi all,

I have just been replacing the pistons in my front brake calipers. The bolts holding the caliper to the front steering/suspension did not have washers and were safety wired in place. Two questions:
1. should there be washers under these bolts?
2. What wire can be used for safety wiring the bolts in place? Must it be stainless steel wire, or are there alternatives?

Thanks

[Jason1]

Hi

Neither the front or rear had no washers on my +2.
I used stainless wire from Frost:

http://www.frost.co.uk/automotive-engin ... wires.html

Jason

[AHM]

Mine have washers.

When lockwire was the norm it would probably have been steel galvanised steel, these days about all you can get is stainless.

[Matt Elan]

While lock wire is a good idea, most production cars just use lockstep and a suitable torque setting on the bolt

[skelteanema]

Have reassembled the left front caliper and lock-wired it into place using stainless steel wire. What a pig of a job. It took me about 10 attempts, if not more. The reason for the difficulty was not the twisting of the wire, but the proximity of the holes in the bolt heads relative to each other. One was in a good location, roughly opposites the opposing bolt, whereas the other had the hole on the opposite side of the bolt head, requiring the wire to be twisted around most of the bolt head. The difficulty was getting sufficient tension on the wire so that it couldn't slip over the bolt head, thus losing tension and therefore reducing its effectiveness. Finally got it done, found the direction of twisting was important, and also not twisting the bit of wire that went around the bolt head helped as it kept the two strands separate. Now working on the front right caliper. At least the holes are in the correct proximity to each other so this should be a lot simpler.

Interestingly, a lot of the bolts on my car have lock wires on them. The most prominant are the exhaust manifold bolts, but also the sump plug and some others. I get a lot of comments about the lock-wiring as many people have not seen it used before and ask why this technoiques was used. I like it as it is easy to see that bolts are still in their correct place.

[UAB807F]

Interestingly, a lot of the bolts on my car have lock wires on them. The most prominant are the exhaust manifold bolts, but also the sump plug and some others. I get a lot of comments about the lock-wiring as many people have not seen it used before and ask why this technoiques was used. I like it as it is easy to see that bolts are still in their correct place.

On my car I can only think of the fuel line inlets on the carbs & rear calipers that are lock-wired, but I agree it's a good visible check. Last winter when I rebuilt the rear suspension I used dabs of red paint on all the driveshaft & suspension nuts to mark where they should be, something I've never done before but seemed so easy and logical at the time.

[fatboyoz]

Skittle,
This is quite informative.
Check out this video on YouTube:

http://www.youtube.com/watch?v=OwFjUX6S ... ata_player


Regards,
Colin.

Have reassembled the left front caliper and lock-wired it into place using stainless steel wire. What a pig of a job. It took me about 10 attempts, if not more. The reason for the difficulty was not the twisting of the wire, but the proximity of the holes in the bolt heads relative to each other. One was in a good location, roughly opposites the opposing bolt, whereas the other had the hole on the opposite side of the bolt head, requiring the wire to be twisted around most of the bolt head. The difficulty was getting sufficient tension on the wire so that it couldn't slip over the bolt head, thus losing tension and therefore reducing its effectiveness. Finally got it done, found the direction of twisting was important, and also not twisting the bit of wire that went around the bolt head helped as it kept the two strands separate. Now working on the front right caliper. At least the holes are in the correct proximity to each other so this should be a lot simpler.

Interestingly, a lot of the bolts on my car have lock wires on them. The most prominant are the exhaust manifold bolts, but also the sump plug and some others. I get a lot of comments about the lock-wiring as many people have not seen it used before and ask why this technoiques was used. I like it as it is easy to see that bolts are still in their correct place.