Noisy Class 08?

[thx712517]

I've got a Hornby R3484 Class 08. Locomotive runs well, has an hour and a half of run-in time all told, in half hour increments going forward or reverse throughout the throttle range. Running in was spread out over a few days to avoid overheating anything and causing issues. However, it's still a noisy thing. Gear groan I would say, if that makes sense. Are they known to be noisy, are my ears too sensitive, or should I be looking for an issue? How long does it take for it to be considered run in, compared to the estimated 100 hour lifespan of the motor?

[SWT442]

Sounds like it could be dry bearings. I've had the same on one of mine when it was brand new (Modelzone exclusive of 09019), and traced it down to the small bearings that the worm gear shaft sits in. The shaft on the motor sits in one as well, so might be a culprit as well.

 

This link to a chassis on eBay shows what I mean. Motor shaft is protruding in the first picture, and in the last you can see the shaft of the worm gear, thought if I'm right there's another bearing on the driveshaft end of the worm which is under the DCC socket. It all comes apart easy. Just a small drop of a suitable model oil should cure it.

 

I've found some of Hornby's other diesel models suffer the same problem with dry bearings on the worm gear. I've personally had Class 50, 56 & 60 with the same issue. One of the Class 56's turned up seized and needed both gear towers stripping apart, as some awful grease had been used that had turned to the consistency of clay! Was all cleaned up and runs a treat now.

 

Andy.

[Pandora]

If the noise is screech, this was quite common on early Hornby  08 models

[dave56]

30 minutes ago, Pandora said:

If the noise is screech, this was quite common on early Hornby  08 models

 

I have had  09 "Dick Hardy" from new and the screech was awful until I managed to get lubricant to the right spot.

Edited October 16, 2019 by dave56

[MikeParkin65]

Only to add my experience  and not to gloat but my D3509 is silky smooth and quiet. This matches my experience of all recent Hornby models incl the main range 31 and the Railroad 40 and 47 (bought for their TTS chips then sold on).

[34theletterbetweenB&D]

Some diagnostic hints in your other thread on the subject

 

19 hours ago, thx712517 said:

 Gear groan I would say, if that makes sense. Are they known to be noisy, are my ears too sensitive, or should I be looking for an issue? How long does it take for it to be considered run in, compared to the estimated 100 hour lifespan of the motor?

It should be very quiet given the running it has had. Never seen hundred hour life quoted for the motor in this model. (That was the life estimate for the little Mabuchi open frame unit much used in a slew of Margate product.)

 

Gear noise/ groaning. May need grease softening or removal. Or could be a gear that is binding on the shaft or against the gear tower walls rather than turning freely. Those would be my top two suspects. Run the mechanism on the bench with some light oil worked down through the gear tower forward and reverse as a first step to see if that flushes out some hardened grease. Messy but simple, and may be all that is required.

[The Johnster]

18 hours ago, dave56 said:

 

I have had  09 "Dick Hardy" from new and the screech was awful until I managed to get lubricant to the right spot.

So you're saying you had a screech on your dick until you got lube on the right spot.

 

Sorry, someone was going to...

[SRman]

I found that the noise was emanating from the intermediate layshaft in the gear train on my 09 (also a 'Dick Hardy'!). This meant removing the top cover and oiling the ends of the layshaft, then reassembling it and running for a few minutes. It has never made any untoward noises since.

Edited October 18, 2019 by SRman

[thx712517]

On 17/10/2019 at 09:23, 34theletterbetweenB&D said:

Some diagnostic hints in your other thread on the subject

 

It should be very quiet given the running it has had. Never seen hundred hour life quoted for the motor in this model. (That was the life estimate for the little Mabuchi open frame unit much used in a slew of Margate product.)

 

Gear noise/ groaning. May need grease softening or removal. Or could be a gear that is binding on the shaft or against the gear tower walls rather than turning freely. Those would be my top two suspects. Run the mechanism on the bench with some light oil worked down through the gear tower forward and reverse as a first step to see if that flushes out some hardened grease. Messy but simple, and may be all that is required.

I don't have much in the way of a work bench, so I set up a loop of track, took off the shell, and removed the keeper plate from the bottom of the mechanism. Then I squirted in a liberal amount of light gear oil and ran it forward and back for some time. Used some canned air and shot it into the gear tower area as well. There was a bit of gel-like clear grease that I was able to remove with a bit of q-tip. 

 

Is there a way to get into the gear tower? It seems to be a cast metal block, with two screws on the top that hold the little circuit board that the DC/DCC chip sits in. There's a screw in the side of the gear tower block, but I'm not sure if that's holding a gear in place or not so I didn't try removing it. 

[34theletterbetweenB&D]

My recollection is that the intermediate gears are retained on push fit shafts within the solid cast block. Once you have the model dismantled enough you will need to inspect the shaft ends, and push the smaller diameter end to release the shaft. (I haven't gone this far on my one Hornby 08, as it ran beautifully once the overheating wormshaft bearings were eased, so don't have any experience on this part of this mechanism.)

[thx712517]

4 hours ago, 34theletterbetweenB&D said:

My recollection is that the intermediate gears are retained on push fit shafts within the solid cast block. Once you have the model dismantled enough you will need to inspect the shaft ends, and push the smaller diameter end to release the shaft. (I haven't gone this far on my one Hornby 08, as it ran beautifully once the overheating wormshaft bearings were eased, so don't have any experience on this part of this mechanism.)

 

The screw on the side of the cast tower allows the weight block to slide off, revealing a plastic clip that holds the worm gear down. The worm gear has a friction-fit cap on one end, made of plastic, that has the clip that connects it to the flywheel. So I pulled it all off, cleaned and oiled the worm gear, then slowly rotated the driving wheels so I could pull bits of grease off the plastic gear. All clean, oiled lightly, and put it all back together. 

 

No change in noise from the unit. To be fair, the grease remaining on the gear was very soft so I think the earlier oil treatment did what it needed to do. The gears rotated smoothly while everything was apart. So I think I've hit the limit on what can be done with this unit, and accept that it's just going to be, at least to me, a noisy runner.