FJ40 Clutch Master Cylinder Leak. Replacement Needed. (1 Viewer)

[Ackcruisers]

Just discovered clutch master cylinder leak inside firewall and outside around reservoir. My truck is a 1976 FJ40 South American truck with a j30 3 speed. The pedal bucket is from an early truck. Can someone recommend a replacement that will work. Here is image of the master cylinder that’s on truck now. It appears to match 1975-1980 master #31410-60041.

Also, the fluid Is almost black and Should be DOT 3 so thinking something is wrong, Would like to replace clutch, hose and slave.

 

[JMZ400]

Not any help on your application, but I can suggest you get it removed ASAP otherwise that fluid will eat your paint to the metal. Ask me how I know

 

[1911]

Can someone recommend a replacement that will work. Here is image of the master cylinder that’s on truck now. It appears to match 1975-1980 master #31410-60041.

Cruiser Outfitters

 

[Ackcruisers]

Cruiser Outfitters

Thanks for link. Just trying to match the right master. It appears that this is match. Part# CLN60041N

 

[hobbes]

Replace the slave with the master is a reoccurring bit of advice here.

 

[Ackcruisers]

Replace the slave with the master is a reoccurring bit of advice here.

Ok, it looks like my slave has the spring on it which is an early version.

 

[cbmontgo]

They are usually inexpensive and easy to find, even on eBay. Just make sure you buy Aisin.

 

[Ackcruisers]

Working on identifying the correct slave cylinder replacement. My clutch MC is OEM# 31410-60041 As shown in my first post. Below is image of my slave. It appears I do not have the A bracket that the spring attaches to. Can anyone tell what slave replacement I need from image below? I think it’s OEM #31470-60071 here is link

 

[Ackcruisers]

I measured the distance between the two mounting bolts on the existing slave cylinder. As shown in image below. I also measured the size of the nut on the end of the bolts that connect to the engine mount. The one with the spring attached is larger at 17mm and the other is 14mm. The flexible hose (8.2ID and 10.5 OD and 17 3/4 approx. long)that attaches from the hardline to the slave appears to be threaded. Not sure the diameter or thread type as I’m not removing until I get new slave. A 14 mm wrench fit over the nut on flex hose (close up image below).

In searching MUD, it appears on some slave cylinders with spring there is a bracket for spring to attach to. I guess I need one of those sourced from someone. Maybe @pardion?

 

[pardion]

I'll check on that bracket. I would just get a M/C and Slave for a 1976, and hose.

 

[Ackcruisers]

I'll check on that bracket. I would just get a M/C and Slave for a 1976, and hose.

Thanks. My transmission and clutch is for 3-speed so not sure if 1976 CM and Slave will work in my situation.

 

[pardion]

I use that combo on everything, 4 speeds, 3 speeds, and Chevy SM420's.

 

[Ackcruisers]

I use that combo on everything, 4 speeds, 3 speeds, and Chevy SM420's.

That’s great and a big help. I’ll bypass the bracket and just go with a 1976 set-up.

 

[pardion]

1976 still needs a slave return bracket, and a softer return spring than the one kinda shown in the photo.

 

[Ackcruisers]

1976 still needs a slave return bracket, and a softer return spring than the one kinda shown in the photo.

Got it. Ok. Let me know if you have the bracket.

 

[pardion]

in stock, PM sent.

 

[Ackcruisers]

Just installed new Aisin clutch master cylinder 1/75 - 7/80 # 31410-60040 (OEM Parts reference). Unfortunately, the fitting on hardline was not the same as the one I removed. While it appeared to be a direct replacement, the threaded hardline did not fit as it should. While the diameter (m10) is same, the depth of hardline threads appears to be different with the Aisin unit I just purchased. Here is link and below is image in my truck. Notice the length of the fitting. It’s too long for the threads on master. Anyone know the proper fitting size and hardline flare type for this master?

removed old master.