78 FJ40 - Clutch slave cylinder failure

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anothernz45 said:
You will have a 5/16 hole punched thru the fork, get a 5/16 or 8mm allen head capscrew then grind head down so most of the hex is gone and use a ball head in a die grinder to form a little depression for the pushrod on your clutch slave to locate in. My fork had slogged out enough that I could pull the capscrew into it with its nut but you may have to enlarge the hole slightly. This temporary fix has ended up remaining there even after a clutch job.
Thats oil on the slave, not fluid - my breather just hangs down the side of the block now. I look on it as rust prevention.

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Great thanks
 
Had a better look at your pics, that's a big hole. No reason a bigger capscrew won't work tho but perhaps of more concern is that broken release bearing spring - it looks like its been hot. They are normally just rusty, I'm wondering about the state of your bearing. As CruiserMatt said, may be better to pull the box and check bearing and pressure plate.
 
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anothernz45 said:
Had a better look at your pics, that's a big hole. No reason a bigger capscrew won't work tho but perhaps of more concern is that broken release bearing spring - it looks like its been hot. They are normally just rusty, I'm wondering about the state of your bearing. As CruiserMatt said, may be better to pull the box and check bearing and pressure plate.
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Bearing seems to turn smoothly, I have fitted a couple of larger washers behind the acorn nut and in front of the lock nut to see what that does. Just going to try and fit that upper-release pin, dont think its broken or is it
 
So update:
I managed to insert the top retaining pin using the tools below. Thanks for the advice. It took a while, but I got there in the end!

Also drilled a piece of metal and fitted to the push rod behind the acorn and infront of 2 locking nuts.

Took the FJ40 for a test drive and the clutch is working as before!!

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The new clutch stuff joy only lasted about a mile. Lost all pressure on the clutch pedal, looked and the master cylinder was empty! Managed to limp back home in first!!

Seems the joint at the new master cylinder and the hard line has a leak and nothing I do will stop it! Tried some PTFE tape, copper washer, nothing but tighten it, and nothing works.
Any ideas??
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Perhaps the flare in the new master is different than your line. Maybe the flare end on you line is damaged - can happen when tightened down when not centered on the face in the master.
 
New parts aren't always good - quality control isn't what it was these days. Have you examined the flare on both sides of the connection.
 
If it's the line that's leaking then either cut off the flare, put a new fitting on and re-flair it or just replace the whole hard line. If it's the MC that leaks, replace it.
Does that line have the correct flare?
 
Pighead said:
If it's the line that's leaking then either cut off the flare, put a new fitting on and re-flair it or just replace the whole hard line. If it's the MC that leaks, replace it.
Does that line have the correct flare?
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Is there different flares? It’s at the joint so not sure which is at fault!
 
Pighead said:
There are different flares.
Is there a crack in the line? Bad threads on the fitting or MC? Is that the correct length fitting?
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The line doesn't seem to be cracked, but I will have to take another look. On the length of fitting, no matter how tight i screw it on the hardline still has movement, will need to take a look. I couldn't find anywhere that makes the OEM hardline still.
 
If the flare is not sealing, redo it, slide nut back as far as possible, use mini cutter ( pipe cutter ) to trim flare off, use flaring tool to reflare, I do single flares, have worked for 25 years, however, that is not DOT and it is up to you. That slave push rod looks to me like the rounded nut it is supposed to pivot on is going too far thru the fork.
 
peesalot said:
If the flare is not sealing, redo it, slide nut back as far as possible, use mini cutter ( pipe cutter ) to trim flare off, use flaring tool to reflare, I do single flares, have worked for 25 years, however, that is not DOT and it is up to you. That slave push rod looks to me like the rounded nut it is supposed to pivot on is going too far thru the fork.
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What size is the pipe work if I want to go down this route? Something like the below?
www.carbuilder.com

3/16" Die Set for Brake Pipe Flaring Tool | Precise SAE Flares

Create precise and secure SAE single and double flares on 3/16" O.D. brake pipes with this die set. Compatible with our #PROFLARE flaring tool.
www.carbuilder.com www.carbuilder.com
 
It looks like the last threads on the end of the tube nut are stripped off.
Something is wrong with your line/flare/tube nut/threads. Most likely preventing the flare from fully seating when the tube nut is fully tightened.

You can buy all the correct parts but care and attention during assembly is even more important.
 
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