998cc no shift - not a worn gear on shift shaft, but internal - any ideas?

[GS1]

Good morning all, my 09 RS SE5 with 36817 miles on it got stuck in 2nd gear awhile back and I limped it home, been doing the research; oil level correct, shift actuator moves shift lever but no change in gear selector. I finally changed out the Angle Rotation Sensor, electrically I can change indicator on dash by rotating the switch, I have manually shifted the trans into neutral by rotating the Shift Drum, I can physically turn the Shift Drum into gear, but with the gear shift lever attached to the Clutch Shaft Ass'y no shift change even though the actuator moves. Any advice or help greatly appreciated.

 

[Snowbelt Spyder]

Can't really comment on the cause off the original problem yet, but when you put it all back together, take care to align the dot on the shaft with the slot in the shifter arm. Then we'll know that part is all good.

 

[stevencovert]

So you see the shaft rotate but no gear changes?

 

[GS1]

yes, that is lined up, thanks for the photo, and yes I see the shift linkage move when shifting into rev or 1st but not sound of engagement, shaft moves freely by hand running or not

 

[GS1]

also I hear a moaning sound some times when trying to shift

 

[Snowbelt Spyder]

The official name of that sensor is Gear Box Position Sensor - GBPS. The manual for later years of SE5’s specifies that it needs reset with BUDS after replacement. I don’t have an 09 manual so not sure it applies to you. I do know that some folks have replaced the thing and it worked out of the box, so they went on their merry way.

Low hydraulic oil pressure will cause the linkage to short stroke or not stroke at all. That’s why oil level is a thing. The hydraulic module oil filter is also a thing. You probably know it as the transmission filter, as I think that’s what is was called back in the day. Check it, if any question, replace it. And yes, you could have a bad solenoid / piston on the hydraulic module that needs replaced.

You can put your wrench on that shifter lever and sequence through the gears manually. Sounds like you’ve done some of that and your transmission itself can shift normally. But you can recheck that if you want. Just don’t do it with the motor running.

I’m leaning at something hydraulic.

Edit. Just saw your photo. Those are some ugly splines, unless it’s just the photo. Any slippage?

 

[GS1]

no worn splines on shaft or lever, I can shift the shift drum with the switch removed and it goes into gear, but nothing happens when moving the clutch shaft, I think it's internal to the shaft and mechanisms not ready to open it up, but I'm going to have to

 

[Snowbelt Spyder]

At this point, I’m not certain what parts you’re calling the shift drum and clutch shaft. The shaft that the lever and linkage is attached to in your picture is what shifts the transmission - sequentially. I’m at a loss as to what you are calling the clutch shaft. I don’t think I can be much help then.

 

[GS1]

yellow is shift drum which connects to the sensor. i turn that shaft and goes into gear

blue clutch shaft assy turning that either with shifter or by hand does nothing

 

[GS1]

im thinking that the end of the clutch shaft is not contacting part #16

 

[Snowbelt Spyder]

yellow is shift drum which connects to the sensor. i turn that shaft and goes into gear

blue clutch shaft assy turning that either with shifter or by hand does nothing

View attachment 170109

Oh. You're turning the end of that shaft that drives the sensor. First I ever heard of anyone doing that. The rest of my confusion is my fault. You're using the correct parts list nomenclature, although in my shop manual, it's called the shift shaft, not the clutch shaft. The OTHER clutch shaft is in the gearbox assembly. This area of the gearbox / shift mechanism is outside my lane. Sorry. Hope you have good luck with it. I trust that you have a shop manual because - as I look at this - you access this mechanism from the other side - removing the entire clutch assembly first. Really hope you eliminate any problem with the hydraulic control module before you have to tear into this.

 

[Chupaca]

Curious...

did you remove the shift arm off the shift shaft to inspect the splines...?? from the picture you attatched it sure looks like the splines are not in that good a shape. Check and see if the lining dot on the shift shaft moves with the lining split on the shift arm. :dontknow:

 

[GS1]

thanks, that's what I thought that I'd have to tear it down. no I have not gotten a manual yet been sourcing specs from the net.

 

[GS1]

yes I have removed and inspected the splines on the shaft and the lever, they are in good shape no wear, I was hoping it was that but it was not to be

 

[GS1]

Good day all sorry for taking so long to get you guys an update. after getting case apart found part of the shift shaft broken, now to get it replaced

 

[Snowbelt Spyder]

That's a first for me. NICE JOB! :bowdown:

 

[safecracker]

Great job in finding that broken shift shaft.

 

[GS1]

all back together short road test all is good, now to clean :spyder2: up and make :spyder2: shine for the weekend oh but wait it's going to rain drats :banghead::banghead: