Ok guys I have a 1991 Civic Ex Sedan. Since i bought it I've noticed a whinning noise when I start driving. It only does the noise when I let go off the clutch. When I push the clutch in it stops. I thought it was the clutch being that is was bad from day one. I replaced it with a stock clutch, flywheel and throw out bearing, but it still does the noise. Can it be the tranny? If it is are the Dx Ex and Si tranny's the same or would I have to get another Ex one. I have access to two Dx tranny's thats why I ask. Any info would help. Thanks guys.

 

maybe the bearing inside the tranny are shot. try replacing the fluid maybe it will help a lil. Honda MT oil of course. It won't necessarily cure you problem, but it might help reduce the noise. If it is your bearings.... than time to rebuilt or get another one.

 

Ok I'll change the fluid and see what happens. If it still does the noise and do have to replace the tranny are the Dx Ex and Si trannys all the same or no.

 

The DX and the SI are the same gears 1-5 but the final drive in the DX is 3.88 and the Si is 4.25. I think the Ex is the same as the SI, not 100% sure.
It sounds like your input shaft bearing is the problem.

 

EX also has a different FD.
It's a pretty rare tranny to come by.
I'd love to get my hands on the FD from an EX myself - a little mix and match with ZC and Si gears and viola!

Anyway, from how I'm reading it, this noise only happens when you are not pressing down on the clutch pedal. Do you get the noise even when you are in neutral? Did you change out the input shaft bearing?

 

Yeah tell about how rare it is to find one. I think im the only one in my area with an Ex Sedan. All I see are Dx's and Lx's.

No noise when its in neutral. Nice and quiet. With the clutch in no noise. When I first take off while being in 1st gear it does it. After I shift to second and have the clutch in no noise but after I release the clutch you hear the noise. 3rd gear does the same but not to loud and it starts getting quieter as I keep shifting. When I start to down shift and get to 3rd you start hearing it again. People have told me that they can hear it when I drive by. No I have not changed the imput shaft bearing. Is that a hard thing to change?

 

I had actually meant to write - pilot bearing, but input bearing was in my head (haven't quite woken up completely yet).
Your description sounds exactly like the symptoms of a bad input shaft bearing.

Here is a great write-up some guy did (different engine, but the steps are similar and the concept is all there)
http://www.d-series.org/forums/showt...ealant&t=14079

I've had my tranny opened a few times and it's not all that bad. If you can do all the labor to remove it from the car then I believe you can certainly handle what's inside of it.

Hardest part for me is getting that clip out shown in #26 on that write-up. You can spread the clip open with a couple flathead screwdrivers, but it take time. I eventually bought a set of snap ring pliers and it's a lot easier.

Tip - wedge something in between the case to keep constant pressure applied so when you do get the clip opened then the case will automatically push over. I use a couple screwdrivers and when I have the clip open I push on the driver handles to pop it apart.

Also be very careful that you don't chew up the threads in that hole while messing with the clip. I killed the treads after manhandling the c-clip out of frustration once and it cost me a tranny case =(

I would suggest you pick up a genuine Honda service manual or a Helms for this... not some cheap Haynes/Chilton undwear book. It costs some $, but is AWESOME to have! Maybe borrow it if you don't want to spend the $. The pdf of it is downloadable, but personally I'm not much of a fan of piracy.