Ahh yes i had this problem in my corolla.
Pretty sure box out is the only way to fix it permanantly!
Hey everyone, you may have noticed my earlier posts regarding speedo sensors. Well i have just realized that the sensor is the least of my problems. I removed the drive gear tonight and checked it out, it was spinning freely and all the teeth looked good. I looked inside the box to find that it looked like the worm gear on the shaft that drives the speedo is in the wrong place on the shaft, and is not meshing with the speedo drive. See pic below (sorry about dodgey pic had to use my phone).
As you can see the worm gear (gold on the right) is sitting to the right of where it should be, so is not contacting the speedo drive gear. The other thing is that there is a clip or wire of some sort (black bit left of worm gear) that is stopping the worm gear moving to the left where it needs to go. I can wiggle the worm gear a little bit, but it wont move past the wire/clip thing. I have no idea how i am going to fix this and i imagine that having a working speedo is required for rego, which is in a couple of months.
I may be totally wrong, maybe the gear is in the correct place, but im pretty sure its not. I cant see any keyway or anything on the worm gear through the hole so im not sure how it is connected to the shaft. I was think maybe i could whack on bit of the clip (im pretty sure its like a wire that hooks into 2 holes in the shaft) break one end and pull it out, but im sure thats not really a good idea. I tried making a tool with a flattened wire to try and remove the clip hoping to be able to slide the worm gear past and then replace it, but no luck. I dont really want to just try and force the worm gear past it, i think its going to make a mess of things if i do.
Any suggestions anyone? I reeeeaaaaalllyyyy dont want to pull the box out and pull it to bits, i need to drive to work!
Pull the box out, pull the box apart, or get a GPS
Peewee
1985 MZ12 Soarer - 1UZ Powered
2013 86 GTS
Haha yes i have a GPS, but i was thinking mr rego inspector wouldnt like that idea much! Maybe i'll just have to go pinkslip shopping.
Cuzzo do you know what caused the issue? Is it that the worm gear has moved over that wire thing somehow?
I haven't got any experience with this sort of thing, but is it possible that the shaft itself has moved?
Looking at the service manual for the W58 it looks like somehow my speedo gear is on the wrong side of the clip!!! How the hell that happened i do not know!? In the manual they just pry the clip out with a screw driver, maybe i will try and make up a more sturdy tool and try it again...
The below pic found on the internet shows how the clips works...
From: http://www.aeu86.org/viewtopic/ae86/p/128100
What I have seen once in the past was that somehow (I suspect jammed cable) the clip managed to 'jump' out of both its holes and allow the gear to move across.
I wonder if in your case that perhaps the clip has moved across a set of holes...? I'd be having a look, and if that's the case hopefully you can 'unhook' the clip and move it back across If you turn the output shaft you might get be able to see the other hole for the clip more rearward...
Cheers
Wilbo
Wilbo you ledgend! This makes total sense now that i can see an actual pic of the clip! I remember when looking in there i saw a hole in the output shaft further up that i thought was some kind of oil hole or something but this makes sense, it does look like the clip has popped out and moved back and popped into the other one! I made up a more sturdy hook out of an old screw driver...hopefully i can pop the end of the clip out and slid it up! Cheers all, stay posted!
Well here's an update - i used my awesome homemade hook tool and i got the bastard spring out of where it was and got the gear drive back in to position! Yeah! But unfortunately after putting the speedo drive back in and turning it over a few times it just popped out again. Either the spring is stuffed and lost all its tension, or the drive gear on the speedo drive is not the right size and its pushing the worm gear off where its supposed to be. Unfortunatley i dont think there is any other way i can fix it without pulling the bastard apart. I tried...thanks for the help fellas!
Have you checked to make sure that the cable and the driven gear aren't stuck?
Also there are different sized gears which is a bit of a PITA!
Cheers
Wilbo
Yeah i pulled the speedo drive out so i could get to the worm gear on the output shaft. It spins freely and its an electronic sender so there is no resistance on that end. It was quite hard to push the speedo drive back into the gearbox when the worm gear was in the correct position however, so it may be that the drive gear is too large! Oh and i just looked over the rebuild and engineering certificated i got with the car. Seems like the speedo never worked lol.....
Hmm it does sound like it might be the gear size difference problem....
I'd be doing a few things...
1) Count the number of teeth on the gear inside the gearbox
2) Measure the OD of the gear on the speed sensor
3) Read what is stamped on the gear that is connected to the speed sensor (It'll have 10:33 or something like that on it)
4) Try and get someone to measure a normal cable driven gear OD
I can't find where I wrote down the different sizes of the speedo gears, but there is a fair difference in size, see below pic... it sounds to me like you have the large internal gear with the large speedo gear...
Do you have an alloy plate gearbox? If so this would have the large internal gear (and would have come with a mechanical cable)... I think that when Toyota changed to the "steel plate" W5x boxes and digital senders they made the internal gear smaller and the external larger...
PS, I have a matched digital set if you get stuck and want to pull the gearbox :S
Cheers
Wilbo
Ok here's what i found:
Drive gear has 10 36 stamped on it
OD of drive gear is 31.37mm
Inner worm gear has 5 whole teeth when counted across
Can anyone confirm if these are matching?
What is the metal gear stamped with?
If its right it will be sometihng like "(34-36) x 10"
Peewee
1985 MZ12 Soarer - 1UZ Powered
2013 86 GTS
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