Clutch Mystery

[tension]

I am not sure what happened to my clutch on my 97 rodeo V6 3.2L 4wd
I drove away for the weekend (800 mile round trip)
Can you believe that on my trip home I broke down a block away from my house. Lucky me
I was pulling ou of a red light. I had the vehicle in first gear, half way through pulling the clutch out to get going, I felt a pop and the clutch pedal fell to the floor. The vehicle jerked and shut off. I pulled the pedal back up and it became jammed at the top.
If this clutch was on a cable I would guess the cable had snapped. But I know this to be a hydraulic clutch so I don't know what it is. I must note that in the last few days i had noticed a sort of roaring, turning, jet engine type sound half way through depressing the clutch pedal. which gradually diminished when the pedal was drepressed fully. The sound was not that loud just enough to get my attention.

Question is what happened?

Will the trannsmission and transfer case have to be removed to fix this problem?

Please help.

[Cat Fuzz]

Sounds to me like the clutch linkage has broken somewhere. The reason why its jammed at the top is probably because the broken linkage is wedged on something. If it is broken linkage, you shouldn't have to remove the tranny. I'm thinking the other noise is unrelated.

[tnut55]

I can't tell you much about a Rodeo manual tranny but I had to replace the clutch in my 90 Isuzu pickup. Here's how it basically works.

When you depress the pedal, it pushes hydraulic fluid out of the master cylinder into the slave cylinder.

When the slave cylinder extends, it actuates an arm extending out of the tranny and pushes a pilot bearing against the clutch plate to release it.

The clutch pedal returns after you release it because of return springs in the master cylinder as well as clutch plate pressure will push the hydraulic oil via the slave once you release pressure on the pedal. The clutch wants to stay engaged in default mode, which is why your car lurched and died when the pedal popped.

First, I would check the mechanical linkage under the dash to make sure nothing is broken under there and to verify that when you press the pedal, it is actually trying to push the master cylinder. CatFuzz may be right about the hanging. I would expect the pedal to just hang there as opposed to going all the way down.

If the linkage here is OK, you want to check the hydraulics. Check your fluid first at the master cylinder reservoir. Look for leaks if it is low. I can warn you that these cylinders can fail without evidence of leaking. I just had to replace them on a Mazda Protege and this was the case.

If the oil looks good and the linkage appears to be fine, you may want to set the emergency brake and block the wheels. Crawl under the car and look for the slave cylinder that is near and alonside the front of the tranny. Make sure there are no leaks and it is actuating fully when somebody steps on the clutch. If not, you may have a bad master or slave cylinder. Unless you have obvious leaks that tell you which one is bad, you m,ay as well consider replacing both. This is a dirty job and you only have to do it once, so you might as well replace both components now.

Now, if the slave is actuating and you can see there is enough force to push the mechanical arm going into the tranny, then you probably have a clutch problem. This will entail dropping the transmission to check the pilot bearing, the clutch as well as the mechanical linkage here.

In my mind, the roaring you describe before the breakdown was probably your pilot bearing destructing. Hopefully it wasn't and you find the problem in the cylinders or pedal linkage.

Mark

[tension]

Thanks for your help so far.
I went under the truck today.
I figured out the Slave cylinder is working but the lever is offering no resistance. I think the pedal was stuck at the top because when I pulled it up it just had no more room for hydraulic compression since the pushrod was already fully acutated. I manually compressed the pushrod and the pedal once again had play.
I was able to take off a small plate on the side of the push rod housing which gave me access to the lever which seemed to move back and forth without noteable resistance. I am afraid I will have to drop the tranny and t/case. (Right?)
Except for removing the exaust, starter, skidplate/crossmember, driveshafts, it did not seem too bad.
Well then again I have not done it on this vehicle before so It might be harder than I think.
Anyone Out there ever done this before.
Please help.

[tnut55]

Yep, if the lever sticking out of the tranny does not offer any resistance and you have full hydraulic travel...then u will have to drop the tranny.

Generally, the lever keys into a sliding bushing onto which the transfer bearing sits. The bushing rides on a splined shaft coming out of the tranny. The splined shaft mates with the main clutch plate.

When you step on the clutch pedal, it pushes on the lever via the hydraulic cylinders to force the bearing against the fingers of the clutch plate. This in turn forces the clutch plate to spring and disengage.

Again, can't tell u much about a 4 wheel drive Rodeo...Mine is 2WD auto and I have never had (so far) to go under it. So I don't know what it looks like under there.

My pickup was a 4 cyl in-line. I had to use a BIG jack to get all wheels off the ground onto jackstands. My tranny was a small 5 spd so I used a floor jack to lower it. I would recommend a transmission jack if ur going to do this.

DRAIN the transmission before u start. If u don't...u will wish u did. The oil will start flowing as soon as u remove the driveshaft.

I replaced the clutch as well as the pilot (transfer) bearing. Biggest problem for me was getting to the bolts on top of the tranny where it was bolted to the engine. Except for that and laying in oil in a cramped space without a proper transmission jack, the job was not too terrible.