(450/452) Unable to shift gears with engine on, clutch actuator?

[SkyVelleity]

Hi all,

I’ve just got my hands on a Roadster that’s been sitting for a bit over three years, I’ve got the engine running smoothly, and with the engine off it will happily switch into reverse and first gear, however with the engine on, if I try placing it in reverse, or drive, I simply hear a loud, repeated clicking sound, quite a hefty one, as well as the revs dying down in line with the clicking, almost thumping, and it will simply refuse to go into gear (although I suspect not for a lack of trying)

I’m not sure about other models, but it will also refuse to start in reverse or drive, asking me to shift into neutral fast. Understandable.

Thanks to the transmission being constant mash, rather than synchromesh, I suspected the clutch was at fault, as this somewhat remind me of what I would expect to happen if you tried changing gears in a constant mesh transmission, without the clutch properly pressed in. I may be mistaken, as I only have a little experience with them. 

Throwing a camera under my car, I saw that the clutch actuator was incredibly slow, and didn’t sound all that happy at all.

For reference, I also looked at the clutch actuator for my happy, healthy, fortwo (450), and saw that the clutch actuator slammed forwards and backwards like you would not believe.

As such, I grabbed a spare clutch actuator from a wrecked 450 I had lying around, however it would not move at all in the roadster.

Not surprising, given the wreck was in rather bad shape.

I then grabbed the clutch actuator off my healthy fortwo, tested it in the roadster, and while it seemed faster at times, still, on occasion, it would actuate rather slowly.

Some contact cleaner on the plugs did not seem to affect this.

I installed it in the roadster, jamming that dam thing against the clutch as hard as I could with one hand, and while it worked once or twice, activating swiftly, and once, when the car was still on jack stands, it even shifted into reverse, upon lowering the car down and trying again, all I heard was that dreaded clicking sound.

From this point onwards, the clutch actuator no longer move forwards particularly fast, nowhere near as fast as it did in the fortwo.

 

Before I forget, I have followed evilution’s guide on servicing clutch actuators on the original roadster actuator, and the one from the scrap fortwo, however have left the one from my working fortwo mostly as is, spare some desperately sprayed in white lithium grease post installation.

Additionally, I have done most of this testing with and without the roadster  connected directly to the aux battery on my Toyota hybrid, and that thing can jumpstart a freight train, so I am not at all concerned about low-voltage issues. 
 

I am wondering if this is an issue with either the power being delivered to the clutch actuator, the clutch actuator, or, perhaps, issues with the clutch itself?

The actuator is behaving slowly when not installed against the clutch suggests the issue lies somewhere in between the ignition key and the clutch actuator, but, as this car rested in a rather humid climate for three years, I would not discount the possibility that the clutch is possibly the main problem here.

 

Any and all suggestions are warmly welcomed, short of getting the thing toes to my local smart specialist I am somewhat lost for ideas. 
 

Thank you kindly for all of your help, I appreciate it more than I can express in words. 

[Wild!]

When you put the actuator on, Did you adjust it with the bolts just loose enough as to just touch the the clutch  lever by feel and then push it in about an 1/8 of an inch further then tighten the bolts. If not, this might be your problem. If it is, you may have to adjust it back and forth ever so slightly to get it to shift properly.   

[SkyVelleity]

1 hour ago, Wild! said:

When you put the actuator on, Did you adjust it with the bolts just loose enough as to just touch the the clutch  lever by feel and then push it in about an 1/8 of an inch further then tighten the bolts. If not, this might be your problem. If it is, you may have to adjust it back and forth ever so slightly to get it to shift properly.   

Hi Wild, thanks for your reply!

I pushed it in with what I felt was around 5KG of force, but I'm not sure it would have moved 1/8th of an inch.

I'll try again and aim for 1/8th, and report back.

Thanks again, I really appreciate it.

[Nigel]

Also inspect the clutch fork when you have the actuator out.  Many 450s have been known to wear a hole through.

[Wild!]

As Nigel says above look at that too, he's right on that. 

[SkyVelleity]

Thanks everyone for the advise, and sorry for the late reply.

Just thought I'd update everyone on how things have gone:

While the clutch fork on the Roadster was fine, I did notice it was pretty much worn through on one of my ForTwo's, so that's rather interesting to note.

 

While I said earlier that I pushed in the clutch actuator as hard as I could, I tried again, and managed to get it quite a bit further, to the point at which it totally bottoms out. 

This allowed the car to switch between gears like desired, however when the clutch is pushed in, and the car is moving, I hear something of a scraping sound.

I am guessing this is because the actuator is now horribly miscalibrated.

I will now see if I can find someone with the clutch actuator tensioning jig and an MB-Star, have them tension it properly, and then have them re-teach the clutch actuator.

Again, thank you kindly for all your help, it was greatly appreciated!