Is my 722.6 F*!%ed?
Is my 722.6 F*!%ed?
Hi Lads,
I've got a very bad vibration in 5th gear on lift off. It's only in 5th gear and only when I let the throttle off, under load its fine, and if I let the throttle off slowly it doesn't happen. I've checked the nut on the output flange, but its tight. Any other ideas? I'm stumped at this one!
Thanks
Mat
when have you set the lockup clutch to engage/disengage?
i had a rumble once when my lockup clutch solenoid was giving me problems.
like not disengaging and it felt like driving with a solid flywheel until it disengaged.
Are all your drivline joints solid or are there any rubber flex joints.
The converter is set to engage at 90kph, and does so normally, with a noticeable drop in revs, but the noise is the same, locked or not. It happens at all speeds in 5th, but is worse at higher speeds, and is worse at part throttle. Fully off the throttle it is noticeable, but is very bad at that point in the throttle when power is just taken up by the gearbox.
There are no rubber flex joints.
Here's a short video to give an idea:
https://www.youtube.com/watch?v=N0xFJEhRKBk
Mat
My bet would also be the planetary gears, both are engaged for overdrive.
"Expanded Summary: The turbine shaft drives the front planetary ring gear. The K1 clutch is
turned off and the B1 brake is turned on. This locks the K1 drum, which is connected to the
front planetary assembly's sun gear (this prevents the F1 freewheel from overrunning). This
forces the front planetary carrier to rotate around the held front sun gear. The front
planetary ring gear is linked to the rear planetary ring gear, (thru the rotating front planetary
carrier). The K2 clutch, which is connected to the rear carrier, is on. The K3 clutch , which is
connected to the rear planetary's stationary sun gear, is on. This forces the center planetary
assembly to rotate the output shaft in an overdrive ratio.
SIMPLIFIED
FRONT PLANETARY ASSY. IN REDUCTION DRIVING
THE REAR INTERNAL RING GEAR IN REDUCTION
REAR CARRIER DRIVEN AT INPUT SPEED
REAR AND CENTER SUN GEAR DRIVING
CENTER CARRIER IN OVERDRIVE"
Seanyt:
I didn't drive the car before I bought it, as I got it from a wreckers, I basically bought a half cut, fuel tank, prop shaft, exhaust and rear doors were gone, but I got all I needed, being engine gbox and loom, but didn't get to drive it... you pay a price for cheap!
Just to be clear, it makes the noise in 5th gear, and overdrive.
Sultzi:
So from what you're saying, the overdrive is effectively a 6th gear? does anyone know the final drive ratio of the gearbox when overdrive is engaged?
If it were the planetary gears, would the be heard in other gears where the planetary gears are engaged? or are the planetary gears only engaged in 5th? Like Seanyt said, I don't have a manual to hand, and don't really know enough about Autoboxes to make much sense of it.
4th is 1:1
5th is overdrive 0.83:1 there is no 6th gear.
Exactly as Sultzi said K2 and K3 planetary gears are engaged and if they have wear on there gears youll have excessive play.
Have you tried locking it in 1,2,3 and accelerating up and down, i know my autobox was in 4th before i knew it so would barely get much in the first 3 gears.
Some early 722.6 also have some common faulty like a bushing that wears excessively or needle bearing replacement, overall id suggest getting a 270 or 320 cdi gearbox it will be newer and stronger and have some common problems ironed out.
and will also give you a spare valve body and other bits.
ok... sorry 5th IS overdrive. Now it makes sense.
I have driven in manual shift mode, and it shifts fine, but the noise is still there on lift off. I think I'm going to have to just get a 270cdi, as new as possible.
Can anyone confirm that the 270cdi version has the same bellhousing pattern as the 606 version?
Thanks
Mat