slashdawg00110

I pulled the transmission to check out the troubling whirring sort of noise I was hearing. Before I pulled the tranny, I bought a release bearing, a pilot bearing, a pilot bearing seal and a clutch alignment tool.

Transmission is out. I pulled out the release bearing, and I think it was what I was hearing because when I spin it, I hear a noise very similar to what I heard in the car. Not as loud, but maybe when it's in the bellhousing it sounds louder.

My question is about wear on the nose of the input shaft and whether to replace the pilot bearing. The input shaft nose shows some wear. I saw a darkish ring where I figured it spun in the pilot bearing. Sorry, I was too tired to run in and get the camera to take a picture. I'm assuming I just clean the end off with some brake cleaner and then use some emery cloth on it. Yes?

I haven't removed the clutch, so I just stuck my finger into the pilot bearing to see how it felt. I could see some grease in there but not much. It didn't feel rough, though. I've read differing opinions on whether to just leave the pilot bearing alone if it's not trashed. But I have a new one sitting there, and I've removed most of what it takes to get at it? Is there really a consensus on whether to replace them if they're not bad? The clutch looks good, and I'm not planning to remove the flywheel for resurfacing. I'll take care of that another time.

I also noticed another thing. Behind the flywheel, there's a light coating of oil. Where would this come from?

nick812

I would go ahead and replace the pilot bearing but only if you have a mazda bearing. Dont use a cheaper bearing its not worth the time. As for oil behind the flywheel I whould say a tension bolt seal is leaking. A couple of engines I have pulled have had that problem. If you going all the way goahead and get new clutch kit and anything else that mihgt help you never have to remove it for a very long time.

Midwest 7's

iTrader: (4)

or the rear main seal...
i wouldnt replace the pilot bearing unless you suspect its bad, they are a bitch to get out and rarely go bad.

slashdawg00110

So there's no real consensus on the pilot bearing. I'll look more closely at it and see what kind of shape it's really in.

thanks

REVHED

I'd replace it while you have access to it. They're not hard to remove if you have the right tool or enough ingenuity to make your own. I'd replace the rear main seal as well while you're at it.

Midwest 7's

iTrader: (4)

they say a new pilot bearing is more likely to fail than one thats been going strong for 150k....
the rear seal would also require a lot of work, pulling clutch and flywheel.
might want to replace clutch as well, resurface flywheel, tranny mount.... it could go on and on and on.
just fix what you know is bad or think is about to go bad and call it good.

Mazdahead

I have always fixed what went bad in that area and have never had a problem which caused me to pull the tranny again. The shaft usually has a dark burned look from the pilot bearing, but I would take a good look at the bearing and re-grease it. The throw out bearings don't seem to last much more than the clutch, so if someone replaced the clutch and not the throw out bearing, that was your problem. If there are actual wear marks on the shaft, the bearing may be bad, darkness is ok, but not measurable marks.
The oil is as everyone says, the rear seal, it's not real hard to get at and is worth the effort depending on how long you intend to keep the car.

Good Luck

trochoid

iTrader: (6)

My guess is the marks on the input shaft are from an earlier pilot bearing failure. If the current one is good, changing it out is up to you. If you even remotely suspect the rear main seal is leaking, replace it.

Rx-7Doctor

iTrader: (13)

Well, in my own humble opinion. I've always been a preventive maintenance person. If you go thru all the trouble of pulling a trans I recommend that you replace ALL the parts including having the flywheel resurfaced. If the rear main is starting to leak and you ignore it there is a chance that it will get worse and destroy your clutch. The pilot bearing is not that big of a deal to get out with the right tool. You can either see if a place like Csk or autozone loans them out or your local renta yard or pick up an inexpensive one at Harbor freight. Who wants to go back in and do all that work over again if they dont have to?

REVHED

You must like doing things twice because you didn't do it right the first time. lol The only reason a new pilot bearing would be more likely to fail is if it's installed incorrectly in some way.

Pulling the clutch and flywheel is not a lot work. It's 2 or 3 hours work at the most inlcuding the rear seal, pilot bearing and reinstallation. It's a lot less work then having to pull the gearbox again. Besides, the clutch should be pulled for inspection anyway if it's condition is unknown.

Rx-7Doctor

iTrader: (13)

slashdawg, this should help ease the pain of the R&R process.

https://www.rx7club.com/1st-gen-archive-71/engine-flywheel-stopper-554738/

Midwest 7's

iTrader: (4)

how long does it take to pull the gearbox?
16 bolts if my count is correct.
im just saying if he goes through and replaces everything it could never end..
$1000+ easily.

Rx-7Doctor

iTrader: (13)

$1000.00? A clutch kit is around $180-$275 depending on the type of kit. A rear main seal is around $15.00. Hell, paying someone to do the whole job including parts is less then that.

slashdawg00110

I feel like I started a DoO thread in the first gen forum.

I'm going to take a closer look at the rear main seal. If that's clearly leaking, then I'll take this further. If not, then I'm putting in the new release bearing and putting things back together.

revhed, rx7doctor - i hear what you're saying, but I plan to replace the engine within a year and will have everything apart again. That's when I'll install a clutch kit, resurface the flywheel, etc

Midwest 7's

iTrader: (4)

im talking if he did all his "preventive maintenance".
the way i drive that $180 clutch kit wouldnt get me through a year...
oh wait i only drove the 7 like 10 times so far this year so i guess it would.

Rx-7Doctor

iTrader: (13)

Mkae sure you put some white grease on the input shaft splines and the end. Also put more grease in the pilot bearing to be safe.

jarath

The clutch and release bearing had been done in my RX at some time, and some time later the pilot bearing started making noise. Well... it finally siezed to the input shaft and the car ended up in the middle of an intersection. The pilot bearing welded itself to the input shaft and it was a bitch to fix it. Here is a link to the aftermath. If you have it out, I suggest you replace it because if it does go, it's not a happy encounter and will probably end up with a tow home for upwards of $150. Not to mention what it can do to your input shaft and what it takes to try and fix it. Just my opinion however.

https://www.rx7club.com/showthread.p...=pilot+bearing