1969 220D manual Clutch Bearing Problem - Page 2 - PeachParts Mercedes-Benz Forum

t walgamuth · #16 08-15-2008, 06:01 AM

HOld on there pardner....

If it needs a motor mount the motor actually could be low enough the shift rods are fouling on something. better fix that too.

You can change the tranny lube and so forth, thats always a good idea, but I doubt the grinding is affected by any of that.

Tom W

dabenz · #17 08-16-2008, 10:21 PM

OK, let's back up and take a deep breath.

dpl, the high/fast idle knob is on the lower part of the dash, immediately to the right of the steering column. To the right is to a lower speed. Do you have an owner's manual for the car? If you plan on keeping the car then may I also suggest a service manual? The best bang for the buck is the manuals on CD that you can buy from Phil (click the "buy parts" tab at the top of the screen). Once you do business with Phil you probably won't want to do business with anybody else. Buying parts from here also keeps this "free" web site going. Phil and this site has done a good job of keeping old cars running, too. That CD has instructions for adjusting the working end of the idle speed (hint hint). If you want the paper manuals then perhaps Phil can locate them for you - he's that good.

It's your car and your money, but I can't see the point of changing socks to fix an untied shoelace. The new sock will make you feel better but the shoe will continue to fall off until you fix the shoelace.

Now for the schoolhouse:

Reverse gear doesn't have a synchro, which is why you want a low engine speed when you shift into reverse. The gears in the transmission won't immediately stop when you push on the clutch pedal, in other words, and the lower the engine speed is when you do push in the clutch pedal means the less time you need to wait for the gears to stop. Semi-trucks have big transmissions that take a long time to wind down - that's why they have something called a clutch brake so you can get it into gear when the truck isn't moving. These benz's don't have a clutch brake. Keeping the idle speed low helps. So does a good clutch actuator bleed - the pads will pull completely away from the friction disc. A poor bleed means the gears will never stop - and you have to grind it into reverse. Kind of make sense?

Transmissions have lubricants for a reason. Clean transmission fluid will help the sychros and seals. Won't affect reverse gear, so to speak, but it will help the forward gears, which is where dpl was struggling at the beginning of his job. Transmission fluid is cheap and it's probably time.

Motor mount? Maybe, but at this point my money's on 1) learning how the car wants to operate 2) a good clutch actuator bleed and 3) dirty and perhaps worn shift linkage parts external to the transmission. What's the point of changing the motor mounts if the problem is an easy-to-fix shift linkage? Socks or shoelaces.

t walgamuth · #18 08-16-2008, 11:13 PM

The key is that he says it won't go into reverse no matter how hard he tries. That is not going to be solved by changing the tranny lube or oiling the shift linkage rods.

His clutch is clearly not disengaging.

That can be a bleed problem, or a hanging pilot bearing, or a pressure plate that has a broken finger or two or three.

Yeah, it probably would not drop enough with a bad mount to foul the shifter rods but if its vibrating a lot because of that its not something to put off.

Tom W

bauchty · #19 08-17-2008, 12:24 AM

First time posting and not sure if i should start a new thread on this, but since it's regarding the clutch on a 220... The other night I picked up a '71 220 gasser. in pretty good shape. Although there may be a clutch issue, and I'm wondering where I should start. Fixing up this car is going to be a bit of a learning experience for me, the shop service manuals are already on order.

The issue: When shifting, I must let the rpms go way down or else the gears will grind. Basically this means pushing the clutch in and waiting two seconds or so, then slowly shift. 1st is the worst gear, at a dead stop it's tricky. The issue hasn't occured going from 3rd to 4th. The clutch pedal also feels very low.... it feels like I could push the pedal farther down, the friction point is very near the pedal to the floor. Any thoughts what to look at first. Possibly bleed the hydraulics?? I appreciate any suggestions...

t walgamuth · #20 08-17-2008, 06:43 AM

Yes. Start with a bleeding of the clutch hydraulics....assuming you have checked the brake fluid level. If not then start by looking at the level, since the clutch is fed from the res.

Its good in a way. If the clutch were worn out the friction point would be very high!

Tom W

bauchty · #21 08-18-2008, 01:30 PM

Thanks Tom,

Ah, glad to hear the clutch is likely ok, I wasn't looking forward to prospect digging into that right of the bat.

The brake fluid level is right at the min line. I'll top off and see if that improves shifting. If not I'll bleed the system. I'm actually considering changing out the old brake hoses and flushing the system. ...need to research that a bit more.

appreciate the response...
Bill

t walgamuth · #22 08-18-2008, 07:29 PM

That test only lets off the friction disc, the pressure plate, and pilot bearing could still be causing trouble and they would involve removing the tranny as a minimum.

Tom W

Graminal95 · #23 08-18-2008, 10:17 PM

I've just done a clutch job and did not allow any air to get into the clutch hydraulic system but the clutch still felt really low. I tried bleeding the system and it just made it worse. It looks like you have to reverse bleed the system, at least for the the w123 series, and yours might be the same.

The book says to use a hose to connect the right hand brake caliper bleeder to the clutch slave bleeder. First attach the hose to the caliper bleeder, crack the bleeder open and pump the brake pedal till all air is out of the hose, then attach it to the clutch slave, then open the clutch slave bleeder and pump the brake pedal till all the air bubbles stop coming out of the brake fluid.

I hope this works for you, but I just don't know about the older clutch systems.

t walgamuth · #24 08-19-2008, 12:07 AM

its the same.

Tom W

Cervan · #25 08-19-2008, 04:50 AM

im having this issue as well, im not 100% on what it is either. im having issues with putting the car into gear, at times its easy as pie and works as it should, and others it will not go into gear and if i leave it in gear at a stoplight or something, and have the clutch in it will make a chattering noise and sometimes lurch forward as if something were getting stuck inside there.

t walgamuth · #26 08-19-2008, 05:48 AM

Quote:

Originally Posted by Cervan

im having this issue as well, im not 100% on what it is either. im having issues with putting the car into gear, at times its easy as pie and works as it should, and others it will not go into gear and if i leave it in gear at a stoplight or something, and have the clutch in it will make a chattering noise and sometimes lurch forward as if something were getting stuck inside there.

It sounds like you have a finger broken on the pressure plate and the pressure plate is dragging and not fully disengaging. It should do it every time the car is not moving, though. If you happen to hit it right, and you will if you are very familiar with the car, it won't drag, but it will act up any time the car is dead still. If it gets too bad you might have to shut the car off at each dead stop and engage first or reverse before starting up the car.

Tom

Graminal95 · #27 08-19-2008, 07:34 AM

I wonder if it could be a bad pilot shaft bearing, only allowing the shaft to turn sometime and binding other times.

If it were my car I would disconnect the drive shaft, put the transmission in gear and have someone push the clutch in. Then I would turn the transmission output flange by hand, if it take no effort to turn then the clutch is totally disengaging, if there is resistance then a good bleed might be in order.

t walgamuth · #28 08-19-2008, 10:21 PM

the pilot bearing could cause such problems, theoretically, but I have never seen it personally.

Tom W