Clutch problems

jumper · Post by **jumper** » Sat Apr 21, 2007 7:02 pm

This is engine off and out off gear. When i press on the clutch pedal it goes 75% down then gets real hard then suddenly goes down to the right point.
With the engine on i press down the clutch pedal and it has the problem above then i put it in gear and release the pedal, the pedal comes up but the clutch has stuck disengaged then will suddenly engage and the truck jumps forward.

The master and slave cylinders are ok have fluid and have been bled.

Any ideas on what the problem is please.

Toyhatsu · Post by **Toyhatsu** » Sat Apr 21, 2007 7:16 pm

Probably the engagement bearing (aka thrust bearing) binding on the snout that it runs on. I had this happen due to the bearing moving too far down the shaft and then being able to shift slightly off centre and then bind on the snout. Sort of a friction lock type thing, same as is used on the extendable batons etc...I had to pull out the trans, replaced the bearing, cleaned the snout and changed the clutch disk.

Cloggy_NZ · Post by **Cloggy_NZ** » Sat Apr 21, 2007 7:46 pm

Wonder if it just gummed up with all that mud you have been playing in lately? Has it got a cover on the bottom half of the bellhousing?
Can you possibly get a hose in there, turn it on full tit and clean it out with water? Preferably with the engine running so it sprays it all around. Might take a while to loosen and dislodge any gunk but might save you having to pull the gearbox. That would not be a fun job.
Would be easier if this could be done in a stream or river, pull the bottom cover of the bellhousing if fitted and drive up and down the river a couple of times.

jumper · Post by **jumper** » Sun Apr 22, 2007 6:56 pm

Pulled the cover and half a mud hole fell out :roll:

the clutch fork had no boot and the seal on the cover is not tight.

Watered the clutch and housing, now have the clutch working :twisted:

Cloggy_NZ · Post by **Cloggy_NZ** » Sun Apr 22, 2007 7:08 pm

Sweet

Does that mean you are coming for another play at Terawhiti this Wednesday?

jumper · Post by **jumper** » Mon Apr 23, 2007 10:28 pm

i dont think i will be there as the clutch has the problem back :roll:

it feels like a small stone got in the clutch.

jumper · Post by **jumper** » Mon May 07, 2007 7:09 pm

Is it possible to loosen the pressure plate bolts to see if crap is trapped behind it. Trying to avoid taking gearbox out.

Cloggy_NZ · Post by **Cloggy_NZ** » Mon May 07, 2007 7:27 pm

Is your cover a flat plate of one of those large 45 degree angled pans?
In the latter case you probably could. Just loosen them all off a bit at a time so might be a two man job, one to turn the engine a bit at a time, the other undoing the bolts.
It probably won't be dirt of stones between the pressure, driven plate and flywheel, there is just not enough room for anything larger than a grain of sand to get in between. My guess is the release bearing where is slides up and down the mainshaft is all gummed up, maybe some mud inside the pressure plate itself stopping the fingers from moving.
But unbolting the pressure plate might give you enough room to wash this out.

Cloggy_NZ · Post by **Cloggy_NZ** » Mon May 07, 2007 7:36 pm

Just thinking about it though, are you sure the problem lies down at the pressureplate area?
Have you had the master and slave cylinders apart? Is there a flexible hose which may be old and deteriorated and possible clogged up?

jumper · Post by **jumper** » Mon May 07, 2007 8:50 pm

Yesterday i pressed the clutch pedal it had the problem so i hosed out the clutch again tried the pedal seemed ok turned the engine on moved the 40 in and out the garage clutch was perfect 100%.
Tried the pedal today problem back. It seems like the water is moving dirt or stones about or lubing something and when it dries the problem comes back.

The clutch was bled and seems to be fine.

Aaron · Post by **Aaron** » Tue May 08, 2007 12:53 pm

Leave the cover off and drive through a river a few times using the clutch that might clear it out or you could undo the pressure plate bolts and move it back. Give it all a good squirt with some brake cleaner then move it back into place doing the bolts up graduly.

Mattman · Post by **Mattman** » Tue May 08, 2007 5:21 pm

Definitely sounds like the release bearing is seizing on the input shaft.

Not much you can do except pull the gearbox and check it out.

Matt.

Sadam_Husain · Post by **Sadam_Husain** » Tue May 08, 2007 5:39 pm

for longer term reliability it might be worthwhile getting some mates around for an afternoon and pulling the gearbox out and sorting out the problem properly

if the release bearing is sezieing and the gearbox snout has rusted up and run out of any sort of lubrication the problem won't be going away?

jumper · Post by **jumper** » Tue May 08, 2007 6:44 pm

Had a quick look today :evil:

clutch stuck engaged :evil:

so gearbox has to come out.

thanks for the help

Sadam_Husain · Post by **Sadam_Husain** » Tue May 08, 2007 6:51 pm

when I had to setup my clutch I found Greg at MP Auto parts in Upper Hutt really good :thumright:

Cloggy_NZ · Post by **Cloggy_NZ** » Tue May 08, 2007 6:55 pm

Sadam_Husain wrote:when I had to setup my clutch I found Greg at MP Auto parts in Upper Hutt really good :thumright:

I second that, you'd be hard pressed, if not impossible, to find a nicer, more honest, knowledgeable guy to talk to about brakes and clutches.
He the man.

jumper · Post by **jumper** » Fri May 11, 2007 4:07 pm

The L brackets that hold the gearbox cross member to the frame do not want to come out so that means lifting the cross member over the hump in the L bracket but then the gearbox hits the tunnel above :evil:

It looks like the tunnel will have to be cut

Mattman · Post by **Mattman** » Fri May 11, 2007 6:11 pm

Whats holding the brackets in Jumper?

You don't want to cut the tunnel unless you have to. Does the gearbox not come off the cross member which comes off the L brackets?

Matt.

Sadam_Husain · Post by **Sadam_Husain** » Fri May 11, 2007 6:51 pm

If you lift the vinyl off the floor pan (whatevers left of it?) the whole gearbox tunnel should unbolt from the floorpan to make access easier (got to take the gear and transfer levers out first), then you'll have to workout someway of unbolting the cross member to slide the gearbox out backwards and from underneath.

jumper · Post by **jumper** » Fri May 11, 2007 7:08 pm

I think the captive nuts that hold the L brackets are spinning.
Two bolts that hold the gear box to the rubber mount do not want to move and the bolts on the bottom of the rubber mount stick through the cross member.
Its an 82 fj40 with a small panel that lifts off not the long one.

Cloggy_NZ · Post by **Cloggy_NZ** » Fri May 11, 2007 7:12 pm

If it moves weld it...
If it doesn't want to move, get a bigger hammer...

But seriously, if you need a hand Rob, just let me know.
Got most tools to get the job done
I bet a few spinning captive nuts will be no match for the gas axe :lol:

shodan · Post by **shodan** » Fri May 11, 2007 9:26 pm

spinning nuts wont be a problem if you grind head of with grinder either

jumper · Post by **jumper** » Wed May 16, 2007 4:40 pm

Grinding the bolts off would of meant more work getting the brackets mounted again did not want that.

Cloggy came round and helped (thanks), the gearbox was out with the help of a pry bar and his trolly jack.