brake cylinder honing tool size (1 Viewer)

[froggy]

hi! title says it all, I'm getting prepared to rebuilt my front brake cylinders on my 71. anybody know the size of the honing tool I need? I want to have everything ready when I start the job. thanks

 

[73FJ40]

@froggy

I suggest you determine the hone size from your replacement cups.

For what it's worth, my Jan 1973 front cylinders are marked 1 1/4 inch (almost 32 mm), and according to the OEM parts fiche, the same cups are used from 71 - 73 models.

 

[Tancruiser]

Buy new ones it’s well worth the money .

 

[Dizzy]

This might not be true in every case, but, if you need to use anything more than green Scotchbrite or sandpaper, which is typically used for smoothing primer, then you need a new cylinder. Even the smallest rust pits will take too long to work out with a honing tool. Think of it like this, it is only a polishing that will ensure that the cylinder is thoroughly inspected prior to being put back into service. Duct tape some scotchbrite wrapped around the end of a dowel, and chuck it into your drill.

 

[froggy]

thanks for your help, I'll go with 1.250". I have a 72 part truck with no brake issues so it's just a matter of refreshing them before I put them on my 71

 

[Dizzy]

The rear are smaller. Like 7/8" if I remember correctly.

 

[froggy]

thanks for the information! I have new cylinders in the rear (2 years) so I should be good for now

 

[AirFuelRatioMan]

So, I've been looking everywhere for brake cylinder honing specs. Maximum diameter after honing for the rears, and fronts. Rears are 1" and fronts are 1 1/4". Can't find any information. Was hoping for a generic chart based on size or a percentage of original bore, but no luck.

I have been unable to find front cylinders for my 1985 FJ70 here in Ecuador. US and Australia part numbers don't match up. The old cylinders are original and deeply pitted. I used up two sets of stones on the honing tool getting one rear and two fronts almost straightened out. Which worries me, because I removed quite a bit of material.

If the honing tool is only meant to condition the surface area (remove glazing and light oxidation) then I'm in trouble.

Any help would be greatly appreciated.
Thanks,
Dan

 

[Malleus]

This wasn't a Toyota service operation, AKAIK, so I doubt you'll find the manufacturing specs for the bores. You are probably better off sourcing new parts. @OGBeno may be able to help.