Clutch Pedal and Clutch Master Cyl

[sggaz]

Greetings. We recently purchased a 2000 5 Spd 4WD Highlander. During the first month we noticed the clutch pedal seemed pretty stiff but weren't particularly troubled by it. Then I was out of town and got a call from the family saying the clutch pedal was staying down and not returning when released. Fortunately everybody stayed calm and figured out how to pull it out by foot to get home.

After some research I deduced the clutch pedal bushing may be the issue. So I removed it and found this:

Pic taken after one end of spring manually removed

One side of Support Bracket with Spring removed:

Clutch Pedal where spring engages:

So we bought a new Support Bracket and all clutch pedal bushings and welded and machined the pedal to more closely match the original geometry. Then it was reinstalled and presto...the pedal would still stay down and now it was actually sinking down to the floor, not just hovering in the down position like before.

Looking through the PO's records it was clear some clutch work had recently been done including replacing the clutch slave and repairing the clutch master. This work was done by a Muffler shop.

We removed and disassembled the Master Cyl and found this:

(that Lil stainless plug doesn't belong in that socket)

And this:

(the seal shouldn't look like that and there's a pinhole in it)

Bought a Master Cyl rebuild kit (Toy pn 0431112110), rebuilt it, bled, and reinstalled less the stainless plug. All is well and operating less stiff now.

Note: I've seen the yotatech spring swap but it seems to make the pedal stiffer which would not be good for us and I just wasn't sold on the concept anyway.

 

[sggaz]

It's been about 15 months since we rebuilt our clutch master and it just failed again a week or two ago. We had the same issue with the clutch pedal staying on the floor. If the clutch pedal was held down more than about 6 seconds it would not return when released. Troubleshooting pointed to the clutch master again which was a surprise given the recent rebuild. Once the clutch master was out of the vehicle and opened up it became obvious that there was a problem as evidenced by the black debris in the reservoir and cylinder:





Inspection of the internals revealed another seal rupture:



Neither I nor anyone I know is a clutch expert but I came to the conclusion that our clutch master was an aftermarket unit which we (unsuccessfully) rebuilt with OEM rebuild parts and therefore needed to be replaced. I bought the OEM complete unit (shows AISIN on the casting) from Camelback for roughly $95 and installed today. It works well and it seems that the pressure required to push the pedal is less than before and shifting seems smoother.

We also were careful to fully bleed every ounce of the contaminated fluid out of the system and right now it's all fresh Dot3 Brake fluid.

Here's to hoping this one lasts. :cheers:

The bad news: upon return from a successful test drive the steering rack blew fluid all over the driveway. :AK47:

 

[sggaz]

During the recent swap of the master cylinder we noticed that our clutch pedal bushing was falling apart again. It was last replaced 15 months ago. During that replacement we had noted that the spring had been damaged/eroded by direct contact with the pedal but we chose to keep the spring. We had also recently had a noise, a metallic cogging, coming from the pedal at about midpoint of travel and squeaking. As noted in a previous post the original pedal was badly eroded and required welding and machining and the profile we machined may not have exactly matched the original.

So we decided to put in a new pedal and a new spring. The picture below shows the old spring and the new spring. You can see the erosion in the center of the old spring (top). It wasn't sharp but the geometry mismatch probably wasn't good for the bushing.



We also found that the Husky floor mat might be interfering with the clutch pedal movement and have taken the mat out for now and will probably notch it and put it back soon. Results: First test drive was good, no noise, no cogging. Hopefully we won't need to deal with this again for several years.

If you choose to do this there's a good chance that you can re-use all of the other bits and pieces that attach to the pedal (bushings, bump stops for switches) unless they've somehow been abused.

The part numbers we purchased are:

Pedal 31310-35050 ($53.66) and Spring ($12.14) purchased through Camelback online. I also found two websites that helped me identify part numbers:

toyomotorparts.com (includes illustration/exploded views but obscures some of the part numbers)

toyota-usa.epc-data.com (includes full part numbers but no illustrations)

 

[sggaz]

Another clutch master issue

Just about 16 months since putting in a new clutch master it has failed:



The seal is damaged. Swapped with a rebuilt unit from Napa and running fine again. Planning to bleed the clutch at oil changes to try to flush out contamination more frequently.

Any other ideas guys?

 

[Kanoe]

Spring

That sucks about the master cylinder. I know nothing about that, just wanted to chime in on the spring issue, if it should come up again.

I have been using the linear spring for 60,000 km now. No issues. It takes a couple of days to get accustomed to the slightly heavier feel but the difference is not great. I suppose it depends on what you use for a spring. Still a far lighter clutch than the work truck I drive.

Good luck.

 

[foo]

...we noticed that our clutch pedal bushing was falling apart again. It was last replaced 15 months ago.

Thank you for explaining that the clutch pedal P bushing lasts just over a year, as I have been scouring the forum for information as to how long the cheap plastic brittle OEM u-shaped P bushings last!.

we had noted that the spring had been damaged/eroded by direct contact with the pedal but we chose to keep the spring.

After having read your thread, I found my symptoms to be exactly the same as yours.

We had also recently had a noise, a metallic cogging, coming from the pedal at about midpoint of travel and squeaking. As noted in a previous post the original pedal was badly eroded and required welding and machining and the profile we machined may not have exactly matched the original.

I think the EXACT profile is critical, as others, (e.g., Rockdawg84) have found their P bushings lasted only as long as yours did, when re-using the original brake pedal:

The picture below shows the old spring and the new spring. You can see the erosion in the center of the old spring (top). It wasn't sharp but the geometry mismatch probably wasn't good for the bushing.

Thank you for that photo as the spring I worked on was similarly eroded about 1/4 of the way through.

The part numbers we purchased are:
Pedal 31310-35050 ($53.66) and Spring ($12.14)

Thanks for the part numbers. I priced out an OEM-to-OEM replacement to be about $150 ($100 for the pedal and $25 for the double-coil torsion spring and $25 for the QPQ bushings) at the local stealers.

I don't think the pedal can be re-used with the OEM P bushing as all reports I've seen show that the bushing lasts about a year with the old pedal assembly.

Of course, nobody seems to be checking these, so it could be that even a new pedal tears up the P bushing within a year.

How is your P bushing holding up today? Is it still there?