Help - stuck on road 722.3 no 3rd/4th gear - Page 7 - PeachParts Mercedes-Benz Forum

ps2cho · #1 01-02-2012, 11:33 PM

Fixed parking pawl today -- The little ball that sits inside the yellow guiding unit fell out....

Drove the car and there is still the low level clicking noise

What the hell do I do now? Just drive it and see if it goes away? Very frustrated. Car shifts perfect again, I cannot see any reason for this noise. I don't get it.
Maybe it needs a good run on the freeway? I'm just not sure where to go from here.

Stretch · #2 01-03-2012, 04:38 AM

I haven't a clue - could it be the governor knocking on something?

How's the speedo drive?

ps2cho · #3 01-03-2012, 12:14 PM

I pulled the gov cover off and made sure it was pushed out as far as possible, so I know its not the cover, and I triple checked the gear. It looked fine, I spun the output shaft and the gear engaged and spun fine -- the axial support was locked in the correct place...

The speedo drive is wonky (it always has been), but maybe that is it when I put it back in. I'll disconnect it and see if that stops the noise.

ps2cho · #4 01-03-2012, 03:03 PM

Pulled speedo cable out....no change.

Ugh. Other ideas?
I really don't want to get a reman transmission because of this. I feel like I am so close here...

Clicking noise is road related, not engine speed related FYI.

Stretch · #5 01-03-2012, 03:15 PM

So if you drove down a hill in neutral you'd hear the clicking?

ps2cho · #6 01-03-2012, 11:14 PM

Haven't tried that to be honest...Guess I can see if it does it when switching into neutral although I am not sure if that really eliminates anything since the rear half of the transmission is still spinning right?

Is there a way I could safely jack up the rear end and have a helper accelerate a little so I could pinpoint the noise? Would that work?

Stretch · #7 01-04-2012, 04:51 AM

I was just thinking that if you coasted in neutral for long enough and you were still able to hear the clicking then that would indicate that there was something up with the tail cone section and the physical connection to the rear wheels.

No disrespect meant but my guess is that there is something up with the parts you've taken to bits.

If this clicking is related to the output shaft turning I'd jack up the back wheels and turn the propshaft by hand to see if the click can be reproduced that way. I'd then remove say the secondary pump - turn the propshaft again - see if it still clicks... If so then remove another bit - turn the propshaft again...

...keep on turning that propshaft until it don't click to more!

This plan of attach though is only appropriate if the click is indeed induced by the rear wheels turning the output shaft - i.e. at that end of the transmission.

ps2cho · #8 01-06-2012, 08:14 PM

Couldn't isolate it by spinning propshaft by hand so I disconnected the propshaft completely, car is up on all 4 jack points and I turned on the engine. With my stethoscope I hear the ticking. It sounds like its still coming from the governor. It's still very difficult to find it because its metallic in nature so it echos and vibrates, but its loudest near the middle, but more towards the rear on the governor side.

So could my replacement governor be bad? Still seems very weird though.

At least I know its not driveshaft related. I wanted to get that off the list immediately so there was no doubts going forward.

ps2cho · #9 01-06-2012, 09:16 PM

I think I just figured it out. This all adds up now. Ok. *thought process kick in*

1) This clicking makes no sense in regards to damage other than the governor + output gear.
2) Clicking makes no sense for bad governor. No shifting WOULD because it has a plunger in it. Clicking does not.
3) Clicking noise still SEEMS to be coming from rear end.
4) Car drives and shifts normal other than the noise.

So I went back to my spare transmission I took the GOOD governor out of and put my chewed parts governor + output gear back in it...

....I noticed though that where the output gear goes in, there is a small notch on the shaft that clicks and holds, but when I pressed harder, it POPPED into place. I can't be 100% sure, but I don't believe this happened when I put the good gear into my wagon. I'm very doubtful that I pressed it in this hard because everything else kind of just snugly fit in without much effort.

If that's what I did, then it explains it because its a couple millimeters out of place and the clicking could be the governor slipping.

If this fails I give up LOL. We'll find out early next week when I take the rear cover off for the third time now.

Third times the charm right?

You can see it in this photo I took previously. Right deep in the transmission you can see the notch: It fools you because it clicks first, then POPS with more pressure into the hole. Who would have known...I'm young and dumb

Stretch · #10 01-08-2012, 06:46 AM

I hope you're right - good luck and don't give up.

ps2cho · #11 01-10-2012, 09:47 PM

Got it all open again, and it won't pop in place like it will on my spare transmission. I just don't get it. I KNOW this is the issue because I can see wear markings on the gear showing that its obviously slipping or not quite in the right place, but I cannot for whatever reason get it to slot in. I tried both gears, neither will lock in the groove. I then tested both GEARS in the SPARE transmission and BOTH lock in

so its something with the output shaft apparently. I tried knocking it in with a screwdriver and hammer in case it needed some harder persuasion and it still won't do it.

It seems like there is a spring clip or something where the gear slots into it...maybe its damaged or something, who knows.

Here is the SPARE transmission. You can see it "pops" in...but my wagon's doesn't do this. It just kinda sits in as far as it can, but never pops into the groove like shown below:
http://www.youtube.com/watch?v=XZziX4_BzJM&list=UUVPng-6Ys8Gr9402CRgWiOg&index=1&feature=plcp

Stretch · #12 01-11-2012, 04:07 AM

All I can think of is that you've got some muck in there... but I guess you've cleaned it all out.

Am I right in thinking that there is a spring ring on the shaft that clips into the gear part? I haven't seen this part in the flesh so I need a bit of help understanding.

Do you have a depth gauge to measure the distances in the female end of the gear parts?

ps2cho · #13 01-12-2012, 10:52 PM

I think I got it guys

Yes the spring ring engages into the rear part of the output gear
Took that spring ring off, swapped it with the spare one, and NOW the gear engaged it.

Put everything back together and no noise

I am guessing what happened ORIGINALLY was that the governor without the axial support locked down could move around and it was forcing the output shaft gear backwards...After some wear, when I disengaged cruise control, it jerked it just enough that the gear disconnected from the spring clip and I immediately lost all gears. That was the key event. While I was driving at 5mph for a few miles to the nearest rest stop, it was making the same fast clicking noise (although louder) that I was having trouble with for the last few weeks. Now that the gear is back inside the spring ring, its back in the correct place and now there is no noise.

I put my stethoscope up to the transmission, and I hear some metallic "tinging" noises, but maybe thats just normal. Either way, its not doing the audible tick that I could hear at anywhere over 1500rpm. I revved to 3000rpm and heard nothing.

I wont say mission accomplished until I've driven it for a few weeks, but I am pretty confident I got it this time

engatwork · #14 01-12-2012, 11:35 PM

Good job

.

gerryvz · #15 01-13-2012, 12:13 AM

Good work.

Hoping you didn't use any Meyle or Üro parts in your work on this transmission