Metal shavings in a manual trans

[AussieinNC]

Copied from website list of parts

9. Ring, clip, input shaft to mainshaft pilot rollers *‡
10. Bearings, needle rollers *‡
11. Ring, synchronizer, 3rd to 4th gear *
12. Slider, clutch, 3rd / 4th gear
13. Ring, clip, input shaft to mainshaft pilot rollers *‡

Yes, item 13 is the snap ring that retains the pressed on hub, however, it also forms the support for the roller bearings as well, hence the reference Ring Clip input shaft to mainshaft pilot rollers....

Both these clips are in the small parts kit, according to the site.

Without the ring next to the pressed on hub, the rollers could move back and possibly dislodge or fail.

[79vette]

That was my impression from the website description, but I don't understand how it's possible. This image shows where the main shaft snap ring goes. It's clearly impossible for the roller bearings to ever come into contact with that snap ring, so I don't see what it has to do with keeping them in place.

The smallest diameter at the front of the shaft engages the pilot rollers in the main shaft, so they don't ever get anywhere close to the mainshaft snap ring. And the input shaft snap ring is much larger diameter than the bore in the input shaft that holds the bearings, so it doesn't seem like it does anything either...

[79vette]

Deleted double post

[AussieinNC]

I have looked more closely at the illustration and the item descriptions...

I believe item 13 description is incorrect.

It should say something like Ring, clip retains 3/4 synchronizer hub to output shaft.

The rear end of the rollers will mate against the hardened step on the output shaft where they cant fall out unless the front or rear bearings totally collapse.

[79vette]

Originally Posted by AussieinNC

I have looked more closely at the illustration and the item descriptions...

I believe item 13 description is incorrect.

It should say something like Ring, clip retains 3/4 synchronizer hub to output shaft.

The rear end of the rollers will mate against the hardened step on the output shaft where they cant fall out unless the front or rear bearings totally collapse.

I came to the same conclusion, and reassembled the unit. If it blows up I'll post back with what I find, but I think that's very unlikely. There's only one obvious way to install these rollers and snap rings, so I think the description must just be wrong.

Thanks again for taking the time to look at this!

[70STOVEBOLT]

The wear pattern you are seeing on the OD unit gears is from lack of lubrication, aka “burnt up”. They will probably whine if you reuse them.

[79vette]

Originally Posted by 70STOVEBOLT

The wear pattern you are seeing on the OD unit gears is from lack of lubrication, aka “burnt up”. They will probably whine if you reuse them.

I'm trying to get a new set of gears to replace the damaged ones. We'll see if they are available...


Meanwhile, does anyone know where I can find a spec for clutch disk thickness for an SM465/6.2 diesel?

I pulled the clutch disk while I am waiting for gears and other parts to fix the Ranger overdrive trans, and I dont remember how thick it was when I installed it. I dont want to waste money on a clutch kit and flywheel resurfacing if this the existing one is in spec, but I also don't want to pull the drivetrain again in 10,000 miles for a clutch job... There's only 20k miles on this clutch, but I do beat on it pretty hard and the clutch has been dragging slightly due to a bent throwout fork which may have caused some accelerated wear.

The remaining friction material thickness is 0.3055" +/- 0.0015 around the outer edge of the clutch disk. There is ~0.055" of material above the rivets. Would you run it, or spend ~$200 for flywheel resurfacing and a new clutch?

[AussieinNC]

If it was mine it would be getting a new clutch kit and remember the pilot bearing / bush in end of crank.

Machine flywheel is a mandatory process to ensure clutch works well after all the work.

Also check the pivot ball and release fork for wear...

[79vette]

Originally Posted by AussieinNC

If it was mine it would be getting a new clutch kit and remember the pilot bearing / bush in end of crank.

Machine flywheel is a mandatory process to ensure clutch works well after all the work.

Also check the pivot ball and release fork for wear...

I replaced the fork and ball yesterday. Both were worn when I installed the trans originally and I didn't have time to get new ones, but they are good now.

Turns out Orielly has a "lifetime warranty" on the clutch and flywheel I bought. Took them both into the store intending to match them up with a replacement and walked out with new parts for free, no questions asked. Lol. I specifically asked the guy "you know this is a wear part that requires periodic replacement? It's not broken, just worn out".

And he replied "yup. We also have lifetime warranty brake pads available". I've never heard of anything like it...

[79vette]

Well, here's the latest update on this evolving dumpster fire of a project.

Apparently the bellhousing is 0.010" out of parallel and 0.040" out of concentricity with the engine block. I don't understand how that is even possible. This is the 5th GM bellhousing I've swapped onto a different engine, and I've never found one that wasn't in spec before. I spent 4 hours measuring this tonight and got the same numbers, 5 different times. Has anyone ever heard of a factory bellhousing being off this far? Could a previous owner have smashed the trans on a rock hard enough to bend it or something? I don't see any cracks or obvious deformation, but I don't know...

I drove the truck like this for almost 3 years. It was a little hard to shift, but it definitely ran and drove and until just recently didn't make any objectionable noises. Is that possible with the bellhousing that far out? If not I must be measuring it wrong.

Red numbers are radial misalignment (concentricity) to the crankshaft centerline in thousandths of an inch, and black numbers are out of plane misalignment to the flywheel face in thousandths of an inch.

Also in the process of removing the glow plugs so I could spin the engine, it turns out 7 of the 8 are swollen and cannot be removed. They came out far enough to release the compression and let the engine spin but they definitely don't come all the way out... At this rate sometime in 2023 I'll get my daily driver running again...

[AussieinNC]

IMHO, 0.010 out of parallel is fine, assuming the mounting surfaces of the bellhousing to the block were perfectly clean when assembled. I always use an emery stone on mounting surfaces to ensure they are clean and have no lips or paint buildup.

The 0.040 out of concentricity of the mount hole seems to perhaps point to a pilot bush or bearing being worn, or the hole in the bellhousing is out of round and has probably been out of round from the time it was first machined.

Remember these were mass produced items often from multiple vendors.

If you have another bellhousing, I would replace this one and remeasure.

re glowplugs....dont want to jinx you but I really hope you can get them to seal up again after trying to get them out.

[79vette]

I did clean up the block and bellhousing surfaces before assembling them.

Unfortunately I don't have another 168 tooth bellhousing to use, but I'm going to install the 153 tooth one from my Corvette tonight and check that just to verify I know how to measure. I'll also measure the bore in the bellhousing to see if it is out of round as you suspect; that's a good suggestion. 0.040" should be easy to see if it is out.

I think pilot bushing wear would be a consequence of the bellhousing index being non-concentric with the crank, not the other way around? Unless I misunderstood what you mean. Also 0.010 out of parallel seems like it could cause the input shaft to bind in the pilot bushing and cause hard shifts and premature input bearing wear. Am I just used to modern transmissions with taper roller input bearings and this much misalignment is fine on an old school transmission?

As for the glow plugs, I was getting pretty frustrated after everything last night when I wrote that. They are all definitely stuck, but I didn't try to get them out very hard. Just unscrewed them out of the block and tugged gently with 2 fingers. The first one came out easy, but when I saw the other 7 would spin free but not pull out I assumed they had swollen and didn't fight them. I think it'll go back together (hopefully), and when I get some time I'll make a glow plug extractor like Leroy Diesel sells and change them.

[79vette]

Well, I am now a believer in dialing in bellhousings, even when using original GM parts. I've never found one that was bad before and didn't bother to check this one when I installed it. It's definitely pretty badly off center, and the pilot bushing is completely done after 20,000 miles. It's wallered out over .100" oversize...

I'm going to try to dial this bellhousing back in with shims and offset pins, but might be too far gone...

Edit: The bellhousing is now shimmed parallel to within 0.002" now, except one area about 20 degrees across which is not flat. That area is as far as 0.005" out, but there's no fixing it without having someone grind the trans mount surface on the bellhousing to get it properly flat again. Fixing the parallel alignment brought the bellhousing index to within 0.020" to the crank centerline (was 0.039"), and offset dowels are in the mail to get this lined up.
Again, to reiterate, I've installed 5 of these and I thought bellhousing alignment was fake news until today. I'd never seen one that was bad so I gave up on checking them, but I'll never install another one again without adjusting it for both parallel and concentric alignment.

[AussieinNC]

Try the pilot bush on the input shaft snout, especially after looking at the wallowed out old bush.

I am OCD when it comes to alignment issues, but we need to remember these are mass produced items and are subject to tolerances and "fudging" sometimes.

Also check end float of the crank mount flange...dont be surprised if it is sloppy.

[79vette]

Originally Posted by AussieinNC

Try the pilot bush on the input shaft snout, especially after looking at the wallowed out old bush.

I am OCD when it comes to alignment issues, but we need to remember these are mass produced items and are subject to tolerances and "fudging" sometimes.

Also check end float of the crank mount flange...dont be surprised if it is sloppy.

The new pilot bushing is a good fit on the input shaft. That's one thing I do always check.

What do you mean by "end float of the crank mount flange"? I'm not sure what that is...

[AussieinNC]

Crank end float is the amount the crank can move back and forth along its centerline.

To measure, place a dial indicator in line with the crank centerline , push the crank forward with a bar and zero the dial indicator.

Now push the crank backwards and take the dial indicator measurement.

Standard measurement should be around 0.002 to 0.006...seeing this is a manual trans combo, dont be surprised if you see 0.030 and above.

Let me know what yours measures.

[67 twins]

Around here that's called end play.

[ky-donzi]

I had nearly the exact same thing happen with an advanced adapters ranger a few years back, I had a growling noise and metal shaving. I had mine between a 4bt Cummins and a sm465. The flywheel had a bearing not bushing in it. I attributed the issue to a bearing failure, but after this thread I wonder if it was a alinement issue that caused the bearing to fail. The interior of the ranger looked very similar. Lots of metal in the oil also.

[AussieinNC]

Originally Posted by 67 twins

Around here that's called end play.

And here I was thinking all this time an end play was a Bridge move....

hahahahahaha

[79vette]

Crankshaft end play (or "end float" I guess lol) is 0.0075". If it was over .030" I think I would be pulling the motor to replace the thrust bearings...

The offset dowel pins arrived and I now have the bellhousing concentric to within 0.002". It's shimmed parallel within .005", but the face of the bellhousing isn't flat so that's as good as it's going to get unless I pay someone with a blanchard grinder to true it up. And I don't have time for that.

New clutch, fork, pivot stud and throw out bearing went in tonight. All the glow plugs threaded back in easy and the motor fires right up and idles nice. The plugs are definitely swollen, but I'm not messing with them until I buy/make an extractor tool.

I'm waiting on another UPS box and then the ranger, sm465 and np205 are going in tomorrow. Between the extensive trans rebuild (main shaft, forks, synchros, bearings, bushings, etc) transfer case seal kit, clutch kit and fork/stud, offset dowel pins and shims, oil for all the gearboxes and both axles I'm into this $1500+ on what I thought was going to be a $200 bearing job in the SM465. And honestly the trans was probably fine all along and the messed up pilot bushing/bellhousing alignment was the cause of the noise.

Hopefully this new crap all works...

[79vette]

I also pulled the support rods connecting the clutch master cylinder to the pedal box out of my 88 R30 and built a jig to copy them. I never had these when I installed the hydraulic clutch into the K5, so the master rcylinder is bolted straight to the firewall and it's getting some stress cracks from the repeated flexing. I ground out and welded the cracks and got the new rods installed, so hopefully it doesn't crack again.

I can't try the clutch until I get the ranger installed because there's nothing to keep the disk centered, but I hope the support rods will significantly improve the pedal feel.

[79vette]

Sorry, but I need some more help. I just can't seem to get this right...

I have everything back in th truck. Bellhousing aligned, new flywheel and clutch, new pilot bushing, rebuilt ranger and SM465, new sm465 to np205 coupler and shafts.

The transmission has always sounded like the trans to transfer case coupler is knocking around, and I assumed it was due to worn splines. But now with new shafts and a new coupler and it still does it...

The video starts with everything in neutral and there is no noise. So this seems to rule out anything to do with the clutch. At 0:09 I put the Ranger in gear and let out the clutch, and I get a low growling noise. Up to 0:15 I put the clutch in and out a few times and you can hear the noise start and stop as the clutch disengages. Then I put the trans into second, then third, then the Ranger into overdrive and the rattle gets louder with increasing output shaft RPM. Revving the engine slightly causes the noise to stop.

This drivetrain has always done this since I first installed it, and I assumed it was worn bearings or bushings in the sm465 or a worn coupler but that's all new now. What else could possibly make this noise? I'm out of ideas and don't know where to look next.

Video:
https://photos.app.goo.gl/UtPfchjxWSWfKy169

Edit: does anyone else have a 465/205 behind a diesel? Is this just engine vibration causing the gears to bounce off each other when the transfer case is in neutral? Driving the truck (transfer case engaged and drivetrain under load) it does not make these noises, and my 2wd sm465 gas truck is always dead quiet. I've heard of clutches with a nylon damper in it to reduce vibrations, but mine is allegedly a "diesel" clutch and does not have anything like that.