Excuse for Rear Disk Brake Conversion?

[78Cruzr]

The rear master brake reservoir was low so I took a look and found a small damp area.

I cinched up the fitting and topped off the reservoir and ran some errands.

When I stopped and checked the reservoir it was low again... another look underneath...

 

[pappy]

Wheel cylinders are not that hard to replace. But, sounds like a great excuse to go disk. Much simpler. With the splatter on the spring I'm wondering if the line isn't cracked.

 

[OGBeno]

I'd go disk and FJ80 MC. You'd be done with your brakes forever.

 

[Bad Mojo]

I would get in contact with Poser, he has everything you need minus the calipers.

Also if your in the rear axle I would maybe replace the bearings in it. You already have to open up the rear axle to pull the axle shafts to pull the backing plates unless you want to torch those off.

 

[78Cruzr]

Guess I need to do a little reading...

Any idea of the total cost?

 

[pappy]

I don't want to scare you, but. There are a few parts you will need. Nothing overwhelming, but from a $$ perspective it can add up. There are several write-ups on this conversion in the Tech Links section.

Calipers, Monte Carlo
Rotors. These need to be modified for your axle.
Adapter plates
Brake lines
"Tomb stones"
FZJ80 master cylinder would be dandy, but not necessary.
Proportion valve

Like Paul said, much of this is available from Poser. I bought my plates from Poser, but sourced the rest elsewhere. You will need to do some brake line work to mount the proportion valve, but it's not hard. I have the tools.

 

[78Cruzr]

Okay... did a quick read off of the FAQ page. Definitely straight forward, cost around $200, a long weekend, and light welding.

I may need to replace the line until I can gather the parts...

 

[1911]

Also if your in the rear axle I would maybe replace the bearings in it. You already have to open up the rear axle to pull the axle shafts to pull the backing plates unless you want to torch those off.

+1, and the axle oil seals as well.

Converting the rear to discs was well worth the money for me.

 

[Devil Frog]

just keep in mind the higher a vehicle is lifted, the more burden is placed on the front brakes relative to the rear. So while there is a huge performance befit of disks over drums on the rear on a sorts car, it is almost nil on a 4x4 with a 6" lift and 37's.

 

[OGBeno]

FZJ80 master cylinder

Not the FZJ80 MC.

You want the 1991-1992 FJ80 MC which is set up for non-ABS.

FZJ80 MC is set up for ABS.

 

[pappy]

Not the FZJ80 MC.

You want the 1991-1992 FJ80 MC which is set up for non-ABS.

FZJ80 MC is set up for ABS.

It does matter, but not for that reason. FJ80 is front disk, rear drum. FZJ80 is disk front and rear. I'm running the FZJ80 on my FJ40.

 

[Cruiserdrew]

It does matter, but not for that reason. FJ80 is front disk, rear drum. FZJ80 is disk front and rear. I'm running the FZJ80 on my FJ40.

My understand is this too, but I've not done it. Also used when doing other sorts of RDB conversions that require more fluid to move in the system, like a 14bolt with the disc conversion.

 

[OGBeno]

Interesting. I've never sold an FZJ80 MC for someone doing a disc conversion. I've sold many FJ80 MC's to customers though for the conversion.

 

[78Cruzr]

Almost done... just need to bleed

I took the line off this morning… the drum end of the line was blown out and the other end was cracked through.
Went to NAPA for a replacement… they have prefabbed lines with fittings and flares in various lengths. I bought a 20” for the loop and a 51” one for the main line… www.napaonline.com/Catalog/CatalogItemDetail.aspx?A=BK_8135488_0282384016&An=0
Formed each line to match the route… very simple!

 

[pappy]

Very good. Just so you know, the other autoparts places like O'reilly and Autozone also sell brake line. It's pretty cheap stuff and it does pay to learn how to cut, bend, and flare.

 

[maniacv]

You would use any excuse to upgrade your cruiser

 

[marcfj60]

Why are there so many fluid lines? 2 Wheel cylinders on each wheel and a line between the two to attempt to balance the pressure? That reminds me of the way old air wedge brakes with double actuators work. More effective braking because you are getting 2 leading shoes per wheel but they require more PM to keep them working right.

 

[78Cruzr]

Correct, but t may be a little deceiving... the plastic bleeder tube is shown attached on the far right and going out of view.

Bled the air out of the lines and drove it around the block... all is good!

Once again, Thanks for the help!

 

[sl33p3]

nicely done!