Clutch not working?

[cchase]

I went out to get our 1982 BMW 320i inspected this morning. Found that it wouldn't shift into any forward gear but would grind attempting reverse. It shifts into all gears fine when the engine is not running. My initial suspicion was slave or master cylinder but I want to make sure I'm not missing anything.

Pumping the clutch pedal did not make a difference. Fluid level is okay and the pedal feels fine, as does the brake pedal. Oddly, as you attempt to push it into the gear (apply light effort into pushing it into gear) the engine does bog down slightly (speed drops a bit) until you release effort from the shifter.

So, am I missing anything?

 

[onion]

Is this a car that you drive regularly? Or has it been sitting for a while?

 

[cchase]

Originally Posted By: onion
Is this a car that you drive regularly? Or has it been sitting for a while?



It only gets used a few times each year. It was last driven this spring (May or June I think).

 

[javacontour]

If it starts working after it warms up, almost guaranteed to be either a master or slave cylinder issue.

This is the time of year for that sort of thing as the weather changes.

 

[cchase]

Originally Posted By: javacontour
If it starts working after it warms up, almost guaranteed to be either a master or slave cylinder issue.

This is the time of year for that sort of thing as the weather changes.


It didn't work even after the engine had been running for about 15-20 minutes and everything else was well up to temperature.

 

[Drew99GT]

Maybe the disk/pressure plate are rusted and stuck in place? Maybe stuck to the flywheel?

 

[eljefino]

When you try shoving it into gear the synchros are catching.

I would try (carefully) starting it in first with the clutch to the floor. It will naturally lurch forward. Once rolling, floor the gas then release it, still with the clutch to the floor. You're trying to break the engine free from the transmission input shaft.

I suspect, like mentioned above, rust being a problem. If you had other issues your pedal would feel funny, especially light.

 

[onion]

Yep, +1 on the rust thing. That's why I asked about how much the car sits. I've seen this on tractors and farm trucks a few times. When a vehicle sits for months on end, the clutch can rust to the flywheel. The fix is to drive the vehicle with the clutch held in... bounce it around a little. Generally the clutch will break loose without too much trouble.

 

[Drew99GT]

http://www.camaros.net/forums/showthread.php?t=194562

"There is an easy way to free up a stuck clutch.

Push the car out onto the road.
Warm up the engine in neutral then shut it off.
Put the transmission in first gear and start the engine. This will get the car moving down the road. Give it some gas to get it moving good in 1st.

Take your foot off the gas, push in the clutch pedal, and slam on the brakes. This will free up the clutch.

I have used this method myself and it really works."

 

[eljefino]

I think I speak for everyone here that when you try these shenanigans, get video.

 

[antonmnster]

I'd have a look under the car to see if the slave has been leaking. I'd feel around the master looking for fluid.

It could be rust, but it could as easily be a failed master/slave.

 

[cchase]

I'll take a look around underneath it the next chance I get to see, but there wasn't anything on the ground under the car. Every time the slave cylinder on our Porsche 944 died, the pedal was on the floor and this wasn't the case.

Rust is an interesting theory, I'm a bit leery of taking it out of the garage unless I'm ready to commit to whatever the job may be though so I'll have to hold off on that until another weekend. Not sure why it would stick "this" time given that its usage has been consistent for the past 20 years or so. It doesn't get used in rain or salt but anything is possible, just surprised this wouldn't have happened years ago.

 

[mechtech2]

I don't think it is really rust, but the disc /plate/flywheel can be stuck together in various ways.
And I am still not 100% sure the hydraulics are OK.

So it was fine when parked long ago?
Try one or more of the 'free up' techniques above.

 

[cchase]

Originally Posted By: mechtech2
I don't think it is really rust, but the disc /plate/flywheel can be stuck together in various ways.
And I am still not 100% sure the hydraulics are OK.

So it was fine when parked long ago?
Try one or more of the 'free up' techniques above.


It's never been in the least bit "stuck" in the past. It was fine when it was last used this spring. I'm not sure on the hydraulics being okay either although I could hear something moving down below when I was pumping the clutch pedal.

The next step is crawling under to check the slave cylinder (which is easy enough to replace if need be).

Hopefully I don't have to resort to one of these "unsticking" methods because if that doesn't work, our driveway is at the top of a hill and the car is stored facing out of the garage and it would be very difficult to have to push it back up the hill and of course no way to reverse back in very easily.

I still don't understand the dynamics of is why the engine loads up a bit when I am applying effort to the shifter or why it has no problem grinding trying to hit reverse but doesn't even touch the synchros in the forward gears.

 

[eljefino]

If you are in gear you can slide it into neutral without the clutch. Just load the gas pedal slightly so the engine is neither loading on nor dragging (with engine braking) the transmission.

Worst case, you can stall it or turn the key off.

I'm confident you can get it back in the garage. Maybe get a spotter for the bottom of the driveway.

 

[cchase]

Originally Posted By: eljefino
I'm confident you can get it back in the garage. Maybe get a spotter for the bottom of the driveway.

You wouldn't be so confident if you saw the way it gets tucked into the corner of the garage or the slope of our driveway.

Also, my resistance to try any methods you may refer to as "shenanigans" worthy of videotaping on a 30 year old car!

 

[cchase]

Update: Took it out today to check everything out. I crawled under it and confirmed that the hydraulics were all working properly.

I finally resigned myself to trying the methods suggested here, tried shifting it one last time and it worked fine.

So, who knows what it was or what changed it but it worked fine for 60 miles today. Changed the oil and now it's back in storage until the spring.

 

[urchin]

@cchase: Don't let the car go unused like you did before because you'll possibly have the same issue if not worse than before, something has changed and obviously it is in part due to age and nonuse. Maybe on those occasions when you get a nice dry day during this fall and winter take it out and drive it for 30 minutes or so. I'd try and drive the car at least once every three weeks.

 

[cchase]

Originally Posted By: urchin
@cchase: Don't let the car go unused like you did before because you'll possibly have the same issue if not worse than before, something has changed and obviously it is in part due to age and nonuse. Maybe on those occasions when you get a nice dry day during this fall and winter take it out and drive it for 30 minutes or so. I'd try and drive the car at least once every three weeks.


That would be great but unfortunately there's no real way to do it. When it gets tucked away taking it out takes quite a while. It's been on the same regimen for the past 26 years, for better or worse.

Here's a shot I've posted before of the engine compartment: