It will be interesting to see how well this works next weekend at our maintenance day. Are you sure you don't want to drive to Charlotte next weekend?
Clutch actuator maintenance instructions
10
For preventative maintenance purposes, I decided to remove, clean, and lubricate my smart fortwo (model 451) clutch actuator. This may be desirable if you notice sluggish shifting, shifting noises, or other odd transmission behavior that suggests cleaning the actuator could help. Following are the steps I used to complete the process. If you have other tips/tricks or notice that I've missed something, please let me know so that these instructions can be updated accordingly.
Although I have provided some photos and step-by-step instructions, I want to acknowledge the many smart owners that led the way by being the first to remove, disassemble, and clean the clutch actuator and shared their experiences with owners like me.
1. Ensure that you have the correct tools and supplies. You will need an E10 external Torx (star) socket to fit the bolts used on the actuator, a 10mm socket for the battery terminal, a Torx T20 screw driver, cleaner to help remove old lubricant/debris, and white lithium grease in a spray can. If you do not have external Torx sockets (I didn't), you can find an inexpensive set that has common sizes at Harbor Freight for under $10 (Item # 67898).
NOTE: Previous versions of these instructions included a reference to using brake cleaner, but new information from zorrobyte suggests that brake cleaner may not be safe for plastic parts and that a safer alternative would be "QC Plastic Safe Electronics Cleaner".
As always, YMMV and perform any maintenance or modification at your own risk.
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2. Carefully back the smart onto vehicle ramps and set the parking brake so that you can access the area under the engine. The clutch actuator is behind the driver's seat underneath the engine. The following photo shows the front engine mount, clutch actuator, and starter when looking back toward the engine from underneath the car.
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3. To avoid potential electrical problems or causing error codes to be set, you should disconnect the negative battery terminal from the battery. You’ll need a regular 10mm socket to loosen the terminal. See the owner’s manual for instructions on accessing the battery compartment under the passenger floorboard if you are unfamiliar with the process.
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4. While underneath the car, remove the electrical connector from the clutch actuator by depressing the locking tabs on both sides of the connector and then pulling up.
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5. Use the E10 external Torx socket to remove the three bolts holding the clutch actuator in position. Using the markings on the actuator housing, be sure to note the precise location of the adjustment bolt so that you can reinstall the actuator in the exact same location. You may also want to mark the housing with a Sharpie. Once you remove the three bolts, the actuator will now be free.
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6. After the actuator is removed and while still under the car, you will be able to see the plate and small dimple where the actuator piston makes contact inside the transmission. You can take a rag and clean the old grease and debris that may be present.
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7. You can now take the actuator to a location where you can disassemble it. Using the Torx T20 screwdriver, you can remove the six screws holding the cover on the bottom of the clutch actuator housing.
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8. Now use the cleaner to clean the old grease and debris from the actuator housing. Because of the bits of debris on the inside of the cover, I also used a small paintbrush to clean the cover.
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9. Give the unit some time to dry and then coat the moving parts with the white lithium spray lubricant and then replace the cover on the actuator housing. Make sure the gasket on the cover is clean and that the mounting surface on the housing where the gasket will make contact is also clean to create a good seal. I added some regular white lithium grease to the tip of the actuator piston, but the spray lithium should also be fine. The unit can now be reinstalled on the car.
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10. Place the actuator into position and thread all three bolts into place without tightening them too much. Push the actuator until the adjustment bolt is in the original position noted earlier and tighten one of the bolts to hold it in place. Once the actuator is held in the correct position, you can now tighten the other two bolts.
11. Lastly, you need to reconnect the electrical connector. I chose to coat the contacts with dielectric grease to protect them from moisture before reinserting the plug.
12. You can now reconnect the battery terminal, close up the battery compartment, and take it for a test drive! Be sure to record the date and number of miles in your owner's documentation for future reference.
Although I have provided some photos and step-by-step instructions, I want to acknowledge the many smart owners that led the way by being the first to remove, disassemble, and clean the clutch actuator and shared their experiences with owners like me.
1. Ensure that you have the correct tools and supplies. You will need an E10 external Torx (star) socket to fit the bolts used on the actuator, a 10mm socket for the battery terminal, a Torx T20 screw driver, cleaner to help remove old lubricant/debris, and white lithium grease in a spray can. If you do not have external Torx sockets (I didn't), you can find an inexpensive set that has common sizes at Harbor Freight for under $10 (Item # 67898).
NOTE: Previous versions of these instructions included a reference to using brake cleaner, but new information from zorrobyte suggests that brake cleaner may not be safe for plastic parts and that a safer alternative would be "QC Plastic Safe Electronics Cleaner".
As always, YMMV and perform any maintenance or modification at your own risk.
2. Carefully back the smart onto vehicle ramps and set the parking brake so that you can access the area under the engine. The clutch actuator is behind the driver's seat underneath the engine. The following photo shows the front engine mount, clutch actuator, and starter when looking back toward the engine from underneath the car.
3. To avoid potential electrical problems or causing error codes to be set, you should disconnect the negative battery terminal from the battery. You’ll need a regular 10mm socket to loosen the terminal. See the owner’s manual for instructions on accessing the battery compartment under the passenger floorboard if you are unfamiliar with the process.
4. While underneath the car, remove the electrical connector from the clutch actuator by depressing the locking tabs on both sides of the connector and then pulling up.
5. Use the E10 external Torx socket to remove the three bolts holding the clutch actuator in position. Using the markings on the actuator housing, be sure to note the precise location of the adjustment bolt so that you can reinstall the actuator in the exact same location. You may also want to mark the housing with a Sharpie. Once you remove the three bolts, the actuator will now be free.
6. After the actuator is removed and while still under the car, you will be able to see the plate and small dimple where the actuator piston makes contact inside the transmission. You can take a rag and clean the old grease and debris that may be present.
7. You can now take the actuator to a location where you can disassemble it. Using the Torx T20 screwdriver, you can remove the six screws holding the cover on the bottom of the clutch actuator housing.
8. Now use the cleaner to clean the old grease and debris from the actuator housing. Because of the bits of debris on the inside of the cover, I also used a small paintbrush to clean the cover.
9. Give the unit some time to dry and then coat the moving parts with the white lithium spray lubricant and then replace the cover on the actuator housing. Make sure the gasket on the cover is clean and that the mounting surface on the housing where the gasket will make contact is also clean to create a good seal. I added some regular white lithium grease to the tip of the actuator piston, but the spray lithium should also be fine. The unit can now be reinstalled on the car.
10. Place the actuator into position and thread all three bolts into place without tightening them too much. Push the actuator until the adjustment bolt is in the original position noted earlier and tighten one of the bolts to hold it in place. Once the actuator is held in the correct position, you can now tighten the other two bolts.
11. Lastly, you need to reconnect the electrical connector. I chose to coat the contacts with dielectric grease to protect them from moisture before reinserting the plug.
12. You can now reconnect the battery terminal, close up the battery compartment, and take it for a test drive! Be sure to record the date and number of miles in your owner's documentation for future reference.
1 - 20 of 69 Posts
Tempting, but I'll actually be on my way to Delaware for a week's vacation at the beach.
That can't come soon enough...I've never really had any issues with gear engagement or shifting speed, but I figured a little preventative maintenance couldn't hurt. It was a brief test drive, but the shifting was smooth and fast including double up and downshifts.
I did use some regular white lithium grease on the tip of the actuator piston. Thanks for reminding me and I added that to the instructions.
I also use the regular white lithium grease on the door and hatch locks from time to time.
Just sitting on the toilet makes you tired old man. Who loves ya baby?
It'll be interesting to see how much dirt made it in mine when I do it tomorrow.....
I was wondering why....
This maintenance could not be performed with the device in place so to NOT disrupt the adjustments. It looks as if the cover plate will come off easily and all the cleaning and lubing can be done insitu.
Am I missing something?
Inquiring minds want to know...
John V.
This maintenance could not be performed with the device in place so to NOT disrupt the adjustments. It looks as if the cover plate will come off easily and all the cleaning and lubing can be done insitu.
Am I missing something?
Inquiring minds want to know...
John V.
The screws that hold the plastic plate on are on top. Not easy to get at with it in place.This maintenance could not be performed with the device in place so to NOT disrupt the adjustments. It looks as if the cover plate will come off easily and all the cleaning and lubing can be done insitu.
Am I missing something?
Inquiring minds want to know...
John V.
I DID MY OWN TODAY.
Wow! When going from P to D or R etc. you don't hear the click-click-click. Nice.
With the proper tools and chemicals/grease I would rate this at about a 4 or 4.5 on a scale of 1-10 for difficulty. It's a fairly simple thing to do....even for those who feel they aren't mechanically inclined. Follow the excellent directions and all is well.
After doing this a few times now I can do the whole procedure start to finish in around 5-7 minutes. That is crossing my t's and dotting my i's, checking and double checking not hurrying. First timers may take 40 minutes (assuming you aren't taking pictures along the way).
After doing this a few times now I can do the whole procedure start to finish in around 5-7 minutes.
That is crossing my t's and dotting my i's, checking and double checking not hurrying. First timers may take 40 minutes (assuming you aren't taking pictures along the way).
+1With the proper tools and chemicals/grease I would rate this at about a 4 or 4.5 on a scale of 1-10 for difficulty. It's a fairly simple thing to do....even for those who feel they aren't mechanically inclined. Follow the excellent directions and all is well.
After doing this a few times now I can do the whole procedure start to finish in around 5-7 minutes.
I cleaned and lubed my clutch actuator this morning. I followed the excellent directions and no problems. I'm an owner that's not mechanically inclined....
Mileage, 31,850. On very rare occasions, the car would not show "R" when shifting. That's why I decided to perform this preventive maintenance.
Thanks again to all at sCOA!
That's what I said until I found myself stuck downtown unable to drive home. It took a good 15mins of retrying.
Good Luck
1 - 20 of 69 Posts
