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  #1  
Old 03-09-2004, 04:40 PM
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Grinds when shifting into reverse...

I searched with no luck...

When I shift my car (83 240D manual 4 speed), into reverse, it grinds slightly. (The car is stopped and my foot is off of the accelerator).

So, I can do one of three things to engage reverse:
1) Push it through the grind (I did this before, if I push the shifter very slowly into Reverse, I can ease through the grind.

2) Push the gear shifer into reverse just to the point it starts to grind, then I ease off and try to engage again. This works most of the time.

3) Fail safe method: I shift in to 3rd, then into reverse (clutch depressed the whole time).

The following were replaces 25K miles ago:
Clutch and Pressure Plate
Throw out Bearings
New Clutch Slave Cyl


Any ideas?

Is it possible that my idle is fast, therefore the revs are up and not allowing me to engage Reverse? I do not have a problem with 1st or any other forward gears. If I had a tach, I could check this easily. Would a fast idle cause the gind anyway?

AC

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  #2  
Old 03-09-2004, 04:45 PM
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More likely the clutch is dragging from air in the slave cylinder or the pilot shaft bearing is dragging.

The reverse gears are turning when they shouldn't, and there is no synchornizer on reverse as a general rule -- it's VERY unlikely you would want to engage reverse while moving!

Also possible the pressure plate spring is bad, causing the clutch to fail to release completely.

Peter
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  #3  
Old 03-09-2004, 04:45 PM
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did you replace the shift linkage bushings?
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  #4  
Old 03-09-2004, 05:25 PM
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As psfred said, there is no syncromesh on the reverse gear in this transmission. If it's already sitting still in neutral, press the clutch and shift into any forward gear. They all have syncros, so any will do to stop the transmission input shaft from spinning. Then shift into reverse. Nothing is spinning, so no grinding. For more detailed information about how it works, search for "syncromesh".
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  #5  
Old 03-09-2004, 07:18 PM
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Any fix?

Thanks for the reply(s)....

Rick, this is what I now do 100% of the time. I have no problems doing this as it only takes 1-2 seconds out of my life each time I shift into Reverse. That said:

1) Is there any negative effect from letting this conditon persist?

2) Am I hurting anything by using forward gears to stop the tranny to allow me to shift into Reverse?

If no negative effect other than the added steps for the driver, then I will scratch this one off the list

AC
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  #6  
Old 03-09-2004, 07:36 PM
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So long as you don't grind the gears, it's OK, but you are working the synchros pretty hard.

I'd bleed the clutch master cylinder again, it's difficult sometimes to get all the air out, and it's also possible the clutch master cylinder is bad -- after all, the slave was! If it won't hold pressure properly, the clutch isn't fully disengageing, and this will eat up the synchronizers eventually.

You should also check all the bushings in the shifter linkage, particularly the top set. If you are moving more than one lever at a time, it will grind.

Peter
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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!
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  #7  
Old 03-10-2004, 07:09 AM
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Remember to bleed clutch system backwards by running a line from a brake to the slave. Bubbles like to go up. At this age you should really consider changing the clutch master. If it's "loose" at all the new slave makes it worse.
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  #8  
Old 03-10-2004, 10:50 AM
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Acastell,

I think there is an adjustment screw on the slave cylinder so the clutch can be released further. Not sure though because its been a long time since I worked on manual transmission cars. But you might take a look.


One other thing, is the clutch resoirvoir full?


P E H
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  #9  
Old 03-10-2004, 10:59 AM
Jim B+
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ARRRGH! You may be doing it WRONG!

There's a special trick to engaging reverse on these cars...you grab the shift lever and LIFT IT UP and push it into where "first" should be.

Evidently a lot of people, even those who had these cars from new, never were informed they had to "lift", and a lot of trannys were worn out prematurely.

If you don't know this already, try it. Good luck!

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