22.2 Mm 405 Master Cylinder Adjustment.......

[Kaboota 0]

Hi all

 

I have just had new discs and calipers fitted all round (205 Mi16 , replacing the front brakes with a 307 2.0 hdi set up. I have upgraded the master cylinder for a 405 mi16 unit 22.2 and the brakes keep locking on.

 

After doing some searches I now understand that the servo rod needs to be shortened but need to know by how much?

 

Any other idvice on the above problem would be gratefullt received.

 

Thanks

 

Kris

[mi16nut 0]

Have you got a set of measuring calipers (preferally digital)? If so, measure the internal bore length on both mastercylinders. If you haven't got calipers, try using some wire.

 

From memory the 405 mc is @ 2mm shorter, hence you have no end float & the brakes will lock.

 

I couldn't remove the locknut on the servo rod in the time I had, so haven't put my 405 mc on yet. I'll get round to it one day.

 

Mark.

[M@tt 77]

This might be a bit obvious but if you do use a dial guage make sure you measure the depth of the hole from the back of the plate that sits flush against the servo as iirc the part of the cylinder that sits inside the servo is different lengths between the 205 and 405 versions so just measuring the depth of the hole from the end won't necessarily give you the required depth.

 

When i did mine i didn't use a dial gauge i just did it via trial and error. Got it spot on on the 2nd go. Think it was just a couple of turns or so.

 

You can pull the M/C out with all the brake pipes etc still attached so don't worry if you don't get it right first go as it takes 5 mins to unbolt M/C, pull it up and out of the way and adjust the nut on the end of the push rod.

 

Again iirc you will need to pull the push rod out of the servo in order to adjust the nut as you will probably find the whole rod will just spin if you try and adjust the nut as it's quite tight. It is held in place by a sort of clip so just tug the push rod and the whole thing will come out. You'll probably need to clamp the shaft in a vice or some mole grips to adjust the nut. When you reinsert the push rod make sure you reseat the clip that holds the push rod in place.