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 1987 MACK DUMP TRUCK CLUTCH ADJUSTMENT

CLUELESS

1987 MACK DUMP TRUCK CLUTCH ADJUSTMENT
Posted: Wed Jun 15, 2005 9:01:10 AM

IM LOOKING FOR HELP ON HOW YOU ADJUST A CLUTCH ON A 1987 MACK DUMP TRUCK.

Don

  

RE: 1987 MACK DUMP TRUCK CLUTCH ADJUSTMENT
Posted: Sat Aug 6, 2005 5:32:08 PM

  

I have a 1981 mack rd series and two socalled mechanics have tried in vain to do so. I used to know a guy who made it look easy. I have alot more respect for him now. good luck.

edparker04@yahoo.com
Joined: 2/8/2007
Location: Comanche, TX
Posts: 3

  

RE:1987 MACK DUMP TRUCK CLUTCH ADJUSTMENT
Posted: Thu Feb 8, 2007 10:19:44 AM

  

First you will nees an assistant, a 9/16 wrench and a clutch adjustment tool. If you do not have one you can use a large screwdriver. ( a little harder but it will work).

Have your assistant remove the keys and put them in your pocket. You do not want to take any chance of the engine turning over while you have your hand inside the bell housing removing the retaining bolt. Now while laying under the bell housing you will work through the access hole in the bottom of the bell housing. Using your screwdriver to turn the engine over untill the clutch adjustment retainer is at the 6:00 position. Once that is complete you will then remove the 9/16 bolt and install the adjusting tool. I always liked to have my pedal free travle about two inches from the top. That means when your helper starts pusing down the clutch pedal there will be no movement of the clutch release untill the pedal has traveled two inched from the top. If there is not enough travel have your helper push the clutch down and while he is holding it you can use the tool to screw the clutch plate clock wise to increase free travel and counter clockwise to decrease. Once you have your desired free travle you will reinstall the adjusting lock and start on the clutch brake.

The clutch brake adjustment is on the drivers side where the clutch fork pivot rod goes into the bell housing. You will see a square headed bold that I believe will take a 1/2" wrench to adjust. There is a lock down bolt that can be loosened by using a 3/4" wrench. You will either screw the square adjusting bolt in or out depending on the adjustment you need. I like to adjust the clutch brake to when the clutch pedal is about two inches off of the floor the brake makes contact. Whe the clutch is fully depressed it wil stop the trans from turning. To adjust the clutch brake the clutch pedal does not need to be depressed except for you to test your adjustments. Make sure your helper makes slow movements so you can observe every thing that is going on. Check for worn pins, loose cable or any slack in the clutch cable system. Make repairs accordingly. Some clutches had a built in adjustment cog or gear. I do not know aht chlutch you have but the adjustment procedures are the same reguardless the style of cluth you have. Once the clutch brake has been set you can then tighten the clamp bolt using the 3/4" wrench. Test the operation and readjust if necessary. Affter doing this a couple of times you will find is is not a difficult task. Best of luck and if I can be of any more assistance let me know. I hope this helped.



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