clutch replacement woes & info

Here's some good repair guides for your Tercel :) Look here for help first!
Post Reply
xirdneh
Highest Ranking Member
Posts: 2121
Joined: Thu Aug 04, 2005 11:38 am
My tercel:: 87 tercel 4x4 wagon w/reringed engine, 83 tercel 4x4 wagon w/salvaged engine and 4.1 Diff's
Location: seabeck, washington, USA

clutch replacement woes & info

Post by xirdneh »

Updated and edited "Clutch Replacement Woes & Info"
I bought a clutch kit that included clutch disc, pressure plate, pilot bearing and throw-out bearing. I measured the kit’s clutch disc overall thickness (.344”) and it was a bit thicker than the spare new clutch disc (.32”) I had laying around in the shop. The .32” thick disc was the thickness of disc’s I’ve used previously. The difference (+.025”) did not seem like a big deal so I installed it in the Tercel.
Test driving showed some problems when shifting into first, reverse and extra low. Getting into first was not too difficult but was noticeably stiff and I could feel things that I could not feel on a well working car. It would grind the gears a bit when moving into reverse and would not go into extra low more than one time out of twenty tries.
I thought maybe the clutch cable was off a bit so I tried adding a shim to tighten things up but that helped very little. Then I adjusted the clutch pedal so it had more travel. That did not help either.
Meanwhile I went to a breakfast to meet up with some other retired sheet metal dudes and brought up the subject to two guys who work on cars as much as I do. Both of them thought the thick disc was the problem.
I called the manufacturer of the clutch kit and talked to a tech. He told me that the pressure plate only moved about .063” and that +.025” could be a problem. The specification for the clutch disc thickness was a maximum of .35”. He thought maybe the wrong disc was put in the kit but later let on that there were two different disc’s showing for that kit and that one was not used anymore. Gee, I wonder which one I got.
I was having a problem believing the pressure plate only moved about .063” so I decided to find out for myself. I have a several broken transmissions and some are disassembled. I also have some Tercel flywheels, old pressure plates and throw-out bearings (still in the yokes). I used the .32” thick “new” clutch disc for the test.
I started with the release fork lever, its arm is sticking out of the driver’s side of the tranny and the clutch cable connects to the top end. When you push the clutch pedal down it pulls the cable moving the arm forward. On my good working car the arm is pretty close to vertical when the clutch pedal is out. When the pedal is pushed all the way down, the top of the arm moves abt 1.0”. The problem car moved the same distance.
When the arm moves it rotates a shaft that passes through the side of the tranny into the clutch area (AKA “bell housing”) and that shaft has the release fork attached to it. The release fork rotates forward pushing the throw-out bearing forward about 0.33”. The throw-out bearing pushes against the fingers of the pressure plate assembly thus moving the pressure plate aft and away from the clutch disc about 0.05”. That 0.05” gap allows the clutch to disengage the connection between the engine and the transmission.
I was surprised that the plate moved such a small amount, considering the clutch pedal travels about 6.5” when pushed to the floor. So pedal travel = abt 6.5”, release fork arm movement = abt 1.0”, throw-out bearing movement = abt 0.33” and pressure plate moves to create abt 0.045-0.05” gap between clutch disk and pressure plate..
Further messing around showed that the release fork arm could be moved further than 1.0” but moving it further only moved the throw-out bearing 0.03” more before the fingers on the pressure plate assy. would bottom out. The extra movement did not change the 0.05” gap between the pressure plate and clutch disc.
I will be doing some re-work to install that .32” thick clutch disc.
Well I finally got around to removing the tranny and did some tests with the new pressure plate and disc. I bolted the pressure plate to a flywheel and used the press to depress the plate fingers. The clutch disc was loose but dragged when I tried to move it. There was virtually no clearance. Next I tried it with the thinner (.32") disc. It was a bit more loose than the new stuff but still had very little clearance (abt .008). So I have to conclude that the new pressure plate is faulty too.
Just to double check I tried the original equipment Aisin pressure plate and the .32" disk and confirmed .05" clearance.

http://farm5.static.flickr.com/4053/433 ... cf54_m.jpg
http://farm5.static.flickr.com/4041/433 ... ba6d_m.jpg
http://farm5.static.flickr.com/4047/433 ... d6af_m.jpg
http://farm3.static.flickr.com/2694/433 ... eaa9_m.jpg
Last edited by xirdneh on Wed Mar 03, 2010 8:45 pm, edited 1 time in total.
Love those Tercell 4x4 wagons but they sure suffer from road noise.
takza
Highest Ranking Member
Posts: 4414
Joined: Fri Apr 02, 2004 4:28 am
Location: Tibetan plateau

Re: clutch replacement woes & info

Post by takza »

My way to fix that would be to slip the clutch every chance I got until a few thousands were worn off of it. As long as you don't blue spot the flywheel...doubt if you'd do much damage. So I say...drive it...slip the clutch when you can...it will gradually get better...but don't grind those gears if you can help it?

Those close tolerances shows why a clutch would be sensitive to humidity and slight amounts of oil on the disk.
Give a boy a gun-give a biatch a cell phone-and pretty soon you almost got yourself a police state.

Orwell said: War is peace! Freedom is slavery. Ignorance is strength...

Image
User avatar
ARCHINSTL
Goldie Forever
Posts: 6369
Joined: Sat Apr 30, 2005 1:52 pm
My tercel:: Goldie is a 1986 SR5 attualmente con Weber/also owned the first T4WD in STL in late '82
Location: Kirkwood, a 'burb of St. Louis

Re: clutch replacement woes & info

Post by ARCHINSTL »

xirdneh -
How has this worked out? Who was the manufacturer of the kit? I note you did not mention if the tech person offered to replace the thick disc with the proper one - how come?
Tom M.
T4WD augury?
"Oh, do not ask, 'What is it?' Let us go and make our visit."
T.S. Eliot - "The Love Song of J. Alfred Prufrock"
"Now and then we had a hope that, if we lived and were good, God would permit us to be pirates."
Mark Twain
xirdneh
Highest Ranking Member
Posts: 2121
Joined: Thu Aug 04, 2005 11:38 am
My tercel:: 87 tercel 4x4 wagon w/reringed engine, 83 tercel 4x4 wagon w/salvaged engine and 4.1 Diff's
Location: seabeck, washington, USA

Re: clutch replacement woes & info

Post by xirdneh »

ARCHINSTL wrote:xirdneh -
How has this worked out? Who was the manufacturer of the kit? I note you did not mention if the tech person offered to replace the thick disc with the proper one - how come?
Tom M.
they did not offer, i think because i had not removed it at the time of the call
when i get around to doing the job i plan to send it to them with a note and try and get a new disc and shipping cost (or ask for two disks )
Love those Tercell 4x4 wagons but they sure suffer from road noise.
xirdneh
Highest Ranking Member
Posts: 2121
Joined: Thu Aug 04, 2005 11:38 am
My tercel:: 87 tercel 4x4 wagon w/reringed engine, 83 tercel 4x4 wagon w/salvaged engine and 4.1 Diff's
Location: seabeck, washington, USA

Re: clutch replacement woes & info

Post by xirdneh »

Note: I edited this post and added a paragraph at end to bring it up to date with latest info.
Love those Tercell 4x4 wagons but they sure suffer from road noise.
User avatar
ARCHINSTL
Goldie Forever
Posts: 6369
Joined: Sat Apr 30, 2005 1:52 pm
My tercel:: Goldie is a 1986 SR5 attualmente con Weber/also owned the first T4WD in STL in late '82
Location: Kirkwood, a 'burb of St. Louis

Re: clutch replacement woes & info

Post by ARCHINSTL »

Hmm - you might try Advance (online only in WA). It had two different Rhino kits - not listed now. Or maybe another vendor in your area can get them. One place is http://www.amsautomotive.com/se_kits.php

When we were recently corresponding, I called Rhino (AMS Automotive), which was located right here in the STL area. The number to its tech desk is 800-528-6743. The fellow there was very helpful - he explained that one Rhino is AM, and the "Select" kit is "completely" to OEM specs, and to go with the latter, as it is only a few dollars higher than the other - I think $109 complete from ADV.. AMS does not sell direct, though. I got the impression that they knew their stuff; I'd wager he would give you the specs.
http://www.amsautomotive.com/se_kits.php
Tom M.
T4WD augury?
"Oh, do not ask, 'What is it?' Let us go and make our visit."
T.S. Eliot - "The Love Song of J. Alfred Prufrock"
"Now and then we had a hope that, if we lived and were good, God would permit us to be pirates."
Mark Twain
xirdneh
Highest Ranking Member
Posts: 2121
Joined: Thu Aug 04, 2005 11:38 am
My tercel:: 87 tercel 4x4 wagon w/reringed engine, 83 tercel 4x4 wagon w/salvaged engine and 4.1 Diff's
Location: seabeck, washington, USA

Re: clutch replacement woes & info

Post by xirdneh »

I packed up the bad pressure plate and the rest of the parts that came with the kit and sent it off to Rock Auto per their instructions. Their plan is to send me another kit. They will not be reimbursing me for the $16.00 shipping cost.

Meanwhile I decided not to wait the several weeks I assumed it would take to get the new kit. I bought a kit locally at O'Reilly's and even though it had a different name on the box the brand on the Pressure plate and clutch disc were the same as the previous kit. They were also marked with the same part numbers. I thought "OH NO" but after testing them in the same manner as the returned kit I got the desired results. The clearance between the pressure plate and clutch disc came out around .051" VS the bad kits .005".
Love those Tercell 4x4 wagons but they sure suffer from road noise.
xirdneh
Highest Ranking Member
Posts: 2121
Joined: Thu Aug 04, 2005 11:38 am
My tercel:: 87 tercel 4x4 wagon w/reringed engine, 83 tercel 4x4 wagon w/salvaged engine and 4.1 Diff's
Location: seabeck, washington, USA

Re: clutch replacement woes & info

Post by xirdneh »

Received the replacement clutch kit from Rock Auto
it was the same brand and part numbers as the kit i sent back
i tested the pressure plate and got .048 clearance
i have it installed and it works fine
Love those Tercell 4x4 wagons but they sure suffer from road noise.
User avatar
Petros
Highest Ranking Member
Posts: 11930
Joined: Sun Jan 28, 2007 6:31 pm
My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: clutch replacement woes & info

Post by Petros »

I recently had an opportunity to compare three different new clutches, and thought I would add it to this thread.

I ordered an AISIN clutch from rockauto, total cost was about $103.40 including shipping. This is presumably the same brand as the Toyota OEM clutch. It comes in an AISIN box, and includes a Koyo throw out bearing and a Kachi pilot bearing, all were made in Japan per the label but none of the parts said so (though interesting the packaging came from Aisin American of Torrance California).

I had also thought I was going to need a clutch before this one arrived so I bought the NAPA store brand and received it the next morning, total cost was about $103., plus the local sales tax (if you order it on line it saves about 10 percent). It says made in Japan on the outside label, but inside it was a little different. It has an Aisin pressure plate assembly that is identical to the Rockauto clutch, but it had a LUK friction disk, made in south africa, it also has a Hachi throw-out bearing, but the pilot bearing was made in Korea, KBC brand.

It just so happens that I had a "spare" clutch, a Sachs that I bought new a few years ago from a guy that had it for a number of years (he was going to install it in his Tercel4wd, but the car got totaled and he put the clutch on craig's list after he had for "4 or 5 years" in his garage). I got it cheap, but it was new in the box. I had installed it in a car and only test drove it a few miles, and than I ended up pulling the engine and selling it to another list member. I kept the clutch. It is all marked "made in Great Britain" on both the disk and pressure plate. I do not recall the pilot bearing or T/O bearing brand, they are mixed up with some of my other spare clutch parts. The design of both of these components are different than either the AISIN or the NAPA clutches, but are dimensionally similar. Also, this Sachs clutch may not be their current type since this one may be from inventory as old as ten years ago.

I took these measurements to compare them, and to share here. Note on the disk thickness I compressed the disk since the metal center is almost like a wavy spring, but I wanted to measure the "installed" thickness. So that may explain why it is less than what was measured above.

disk thickness: Sachs 0.294"; NAPA/LUK 0.302"; Aisin 0.305"

Disk surface to rivet: Sachs 0.036" Napa/Luk 0.074"; Aisin 0.042"

Width of friction material: Sachs 1.074; Napa/Luk 1.052"; Aisin 1.12"

Disk weight: Sachs 1 lb 13 oz, Napa/luk 1 lb 15 oz, Aisin 1 lb 11 oz

pressure plate weight: Sachs 7 lb 2 oz, Napa/Aisin 7lb 1 oz, Aisin, 7lb .5 oz

the metal thickness on the pressure plat and cover were all about the same, as was the spring thickness. the Aisin spring had 12 "fingers" and the Sachs had 18, that was about the only difference between them.

The disk surface to rivet measurement is the amount of wearing material, when the clutch is worn down to the rivets, it needs to be replaced. So this indicates how long it will last, presuming the material wears at the same rate. the LUK brand disk has almost twice as much thickness to wear as the others.

All of these brands have a good reputation, and none suffer the extra thickness that was found by Xirdneh above. What brand of disk was the one that was too thick?
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
xirdneh
Highest Ranking Member
Posts: 2121
Joined: Thu Aug 04, 2005 11:38 am
My tercel:: 87 tercel 4x4 wagon w/reringed engine, 83 tercel 4x4 wagon w/salvaged engine and 4.1 Diff's
Location: seabeck, washington, USA

Re: clutch replacement woes & info

Post by xirdneh »

i am not sure what brand it was (memory failing) rhino, brute force come to mind
but the thickness of the clutch disk was not the problem
it was a bad pressure plate
Love those Tercell 4x4 wagons but they sure suffer from road noise.
User avatar
Petros
Highest Ranking Member
Posts: 11930
Joined: Sun Jan 28, 2007 6:31 pm
My tercel:: '84 Tercel4wd w/extensive mods
Location: Arlington WA USA

Re: clutch replacement woes & info

Post by Petros »

I am reviving this thread to add some relavant information.

I recently replaced my clutch with a new Asin pressure plate assy with a new Luk disk, which I had used before, but suffered theis same failure to fully disengage. the clutch drag was so much I could not get it into gear, forward or revers. I had to shut off the engine, fully depress the clutch and put it into gear, than restart the engine. after it was moving it was not so bad to match engine speed and shift up and down through the gears. Reverse was the same problem, it would not go into reverse with the engine running. this is not a good way to drive around town, so I had to find a solution.

I recall this thread and was hoping I did not have to remove the clutch I just installed, but decided to check my cable, auto adjuster and a few other things in the linkage. Inspection appeared that the pedal was not giving the cable its full amount of travel, FSM shows pedal should be about 7 in off the floor (exc. carpet), and about 1" of free travel before it engaged the clutch cable. pedal height was about right, but it took about 2" to engage the clutch cable. the bushing on the clutch pedal was worn and a bit sloppy, which may have contributed to it, the auto adjuster appeared to be working, but the moving parts were a bit stiff, not easily moved.

I had no issue with fully disengaging before with any clutch, but now it did after the new clutch was installed. I thought perhaps my cable had stretch enough so it would no longer adjust, but I put a shim under the cable ferrule where it is stopped on the bell housing (to take up any slack), but it made no difference. So it was not the cable length, but now appeared to be the auto adjuster. or perhaps the work pedal bushing (which is nylon plastic).

I lubricated the auto adjuster parts and worked them so they moved freely, and I decided to back off the pedal stop a little to see it it would allow one more tooth of the auto adjuster to engage (taking up more slack in the cable).

That took care of it, the clutch now fully disengages. I am very relieved I do not have to remove the friction disk, that is just too big of a PIA job.

Make sure your auto adjuster is working properly, parts move freely and are lubricated, before you replace your clutch.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
Post Reply