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Old 12-29-2012, 09:23 PM   #31 (permalink)
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Yeah I didn't do very well with my instructions.

Engine off
Clutch disengaged

Start in 5th and downshift thought the gears to 1st and you slow down, 5,4,3,2,1.

Engine off eliminates the clutch since it is stationary, also the throwout bearing which is stationary when the engine is not rotating.

The transmission has three operational sections. Imput, gear selection. and output-final drive.

Coast down in neutral to test the final drive, noise should become less linerarly and consistently (thats differential output shaft)-carrier bearings.

If the noise becomes much greater as you downshift then it's most likely the input shaft bearing. The highest bearings in the case as well as the one subjected to the greatest sustained loads are your prime suspects unless the test shows differently.

We always replaced all the bearings, and shaft seals, when we went into a transmission. You can check OE prices versus aftermarket, but I would never put cheap Chinese junk in something that was that labor intensive. NSK is a good brand of quality bearing and you may save a good amount of money if you have a locally owned bearing supplier who is reasonable for prices.

Don't let it go too far, I had one transmission come apart 50 feet from the shop on the diagnostic test drive. Fortunately we had plenty of scrap transmissions for parts.

MY doctor was a customer when he was in medical school, he came in one day in his hardbody truck and it would only move in 4th gear. We pulled the transmission down and it looked perfect. After some more checking we found out the input shaft gear had sheared the key off, which meant only foruth gear worked because that gear was actually when the input shaft was directly connected to the output shaft. Of course that RWD Nissan transmission is very different from Honda FWD transmission.

regards
Mech


Last edited by Old Mechanic; 12-29-2012 at 09:27 PM.. Reason: been sick-cant type worth a darn
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Old 12-30-2012, 11:53 AM   #32 (permalink)
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Did this test again, as described in your last post, Old Mech. The main, lower sound does not change, though it does disappear under a 5 or 10 MPH. There is a second sound that appears slightly in second and then louder in first, and that's the one I have heard for years and described yesterday. But the lower sound, the one that has had my concern does in fact reduce in intensity at a regular pace as the wheel RPM reduces, which if I understand your excellent directions, suggests the carrier bearing.

I keep hearing from other guys that it could still be the hub bearing units (too or instead) because despite the honda manual's test recommendations, sometimes the bearings make such noises as they begin to fail even when they offer no measurable play. I suspect that the only way I will find out will be through changing-out parts. But if you have an opinion about the wheel bearing units, I'd love to hear it too.

james
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See my MODDING THREAD for ongoing projects. Black and Green's garage entry has more details. I plan to DIY rebuild this car over decades as parts die--replacing or modding small and major parts until it becomes a different car of roughly the same shape. My fuel economy goal is 60+ mpg while averaging posted speed limits.
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Old 12-30-2012, 01:52 PM   #33 (permalink)
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Since you have an input shaft bearing issue on a transmission you do not want to loose when it comes apart, disassembly is your obvious choice, especially if you have another transmission to use in the interim.

With your stated goal of driving this car for a long time, if you do not have a spare transmission, get one, maybe you will get lucky and it will be a good one. Then you will have no pressure to make hasty repair decisions and the luxury of time to learn to do the job yourself if you wish, or to find a tech who is conscientous and not too greedy to do the presswork to get the bearings on right. If you do it yourself just make sure you avoid pressing on anything but the part of the race that is actually friction fit to the shaft or the outer race if it is friction fit to the housing (very rare).

Doing the job properly and using the proper lubricants as well as your driving techniques will make the repair last a very long time, possibly until the rest of the car falls apart.

If there is still noise from the wheel bearings, then you will know that you wasted nothing taking care of the obvious transmission issues first. I never enjoyed listening to stories about techs who used customers precious financial resources in a "fishing expedition" of repairs, when a more thorough investigation would have saved a large amount of the repair cost. Of course if the tech is just dumb, then he can plead ignorance and keep on wasting money that lines his pockets.

regards
Mech
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Old 12-30-2012, 02:01 PM   #34 (permalink)
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The wheel bearing units will just get gradually worse until they reach a point where it is painfully obvious. Even if they started to come apart the disc brake rotor will not let everything come apart where you would lose control of your car. Long before that point they would really be raising H$%^&*, and the steering would be lousy.

In the old days of drum front brakes the whole hub assembly would come off leaving the driver with a 3 wheeled car. I saw a Rambler wagon loose the right front wheel once. Since it had dual brake circuits the driver still had two wheel brakes. She stopped fro a light and the car tipped over on the backing plate for the right front brake, which was all that was left as the wheel, tire, and drum were gone.

regards
Mech
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Old 01-03-2013, 08:18 PM   #35 (permalink)
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Meet the "new" transmission

It's from a 1993 Civic CX with 90,135 miles on it. I paid $300 and picked it up locally myself. It should have the same gearing as the VX. The number stamped on the case matches the CX/VX/DX/LX trans code: P20/A000. But I could not test the gearing because I did not have a clutch plate. I have 90 days to install and test and return for an exchange if necessary.
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GOALS FOR THE SUMMER POSTED HERE

See my MODDING THREAD for ongoing projects. Black and Green's garage entry has more details. I plan to DIY rebuild this car over decades as parts die--replacing or modding small and major parts until it becomes a different car of roughly the same shape. My fuel economy goal is 60+ mpg while averaging posted speed limits.
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Old 01-03-2013, 08:44 PM   #36 (permalink)
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GEEZEE - '04 Suzuki GZ250
90 day: 79.35 mpg (US)

Sinatra - '92 Nissan Sentra XE
90 day: 37.98 mpg (US)

Super Cub - '65 honda 50
90 day: 170.73 mpg (US)
Thanks: 530
Thanked 1,292 Times in 839 Posts
Sounds like the perfect replacement.

regards
Mech
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Old 01-03-2013, 09:55 PM   #37 (permalink)
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How To: Determine your gear ratios. - Honda-Tech

Do it right and good luck replace everything you dOnt want to pull that thing out more than you have to.
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Old 01-03-2013, 10:45 PM   #38 (permalink)
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Quote:
Originally Posted by Rusty94cx View Post
How To: Determine your gear ratios. - Honda-Tech

Do it right and good luck replace everything you dOnt want to pull that thing out more than you have to.
Thanks! I was thinking of identifying the ratios this way (method from Old Mech, IIRC): "Test to confirm identification of a CX/VX tranny: get an old clutch and mark it at 12 o' clock before pushing the shift rod into the trans, putting it in 4th gear (0.853). Mark the differential. The final drive is 3.25 and 4th gear is 0.853, so 3.25 * 0.853 = 2.77225. Therefore it should take 2.77225 full revolutions of the clutch to make one full revolution of the differential. It should turn 2.77 times and end up pointing a little after 9'o clock to make one full revolution."
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GOALS FOR THE SUMMER POSTED HERE

See my MODDING THREAD for ongoing projects. Black and Green's garage entry has more details. I plan to DIY rebuild this car over decades as parts die--replacing or modding small and major parts until it becomes a different car of roughly the same shape. My fuel economy goal is 60+ mpg while averaging posted speed limits.
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Old 03-19-2013, 09:52 PM   #39 (permalink)
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Thanked 698 Times in 460 Posts
Update: I am finally doing the transmission swap (my 98 DX with 204,000 miles for a 93 CX tranny with 93,000 miles). Have the starter disconnected, the splash guard off, the drive axles disconnected from hubs. Next the clutch cover... it's up on jack stands and I plan to use my shop jack to lower the tranny out, supporting the engine block with a friends shop jack once the transmission mount is disconnected. I'm thinking that while in there I should at least inspect the clutch plate and replace if to my advantage. More later...
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GOALS FOR THE SUMMER POSTED HERE

See my MODDING THREAD for ongoing projects. Black and Green's garage entry has more details. I plan to DIY rebuild this car over decades as parts die--replacing or modding small and major parts until it becomes a different car of roughly the same shape. My fuel economy goal is 60+ mpg while averaging posted speed limits.
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Old 03-20-2013, 08:53 AM   #40 (permalink)
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oooh! Watching with anticipation.

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11-mile commute: 100 mpg - - - Tank: 90.2 mpg / 1191 miles
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