I have a athearn sd7, With the shell off it runs quiet as a mouse. Put the shell on and it "rumbles"loud as can be. I put quarter inch [about] strips [3 layers]of the rubber gloves you can “snatch” from the exam room at the doctors’ office on the chassis where the shell meets the frame. On the sides and inside the top of the shell I put pieces of the foam material I got from Prego sub-flooring cushioning material. Wow! What a difference. I just spot tacked the material in place. Any other ideas. Joe happy jose
This is caused by the body shell being loose. I have an Athearn SD9 (widebody) that does the same thing. I glued a piece of a wide rubber band to each side of the chassis and it cut the noise level down quite a bit.
Well those methods seem a good idea for a noisy shell-----however, I have an old Athearn FM H16-66 (very old, I think) that sounds like Fibber McGee’s closet (me old too) going down the track.
In my case it is both shell and some incredibly floppy all metal axles and metal truck side frames. What was Athearn thinking? So I run it slowly as a big switcher.
You might want to recheck that they don’t have plastic axles. Nearly all blue box engines had wheels with stub axles pressed in to an axle with the final drive gear molded onto it. Reason is they pick up from both sides of the truck and the truck transfers power to the chassis through the mounting point and the over head bracket that the phos bronze strip of metal attached to the top of the motor contacts.
Thanks Brakie, but are the plastic axles and side frames available for such an old Athearn and if so, are they just snap in replacement or is some modification needed to the truck? See, I was thinking I would need to replace the whole truck and gear set if newer ones were available, and then, that the new set might not fit the old Athearn frame at all.
What more can you tell me. Would it help if I put up a picture of my old Athearn’s trucks and frame?
First I had a senior moment…As Jeffery pointed out the axles are metal these slide into the PLASTIC axle housing on the drive axle gear-I haven’t had a Athearn locomotive apart in the last 5 years.
Ok then.
Thankfully Athearn used the standard 14-1 gear ratio which means all gears are interchangeable.So you can use these gears.
The biggest problem you will face is locating the side frames since Athearn has discontinue the TM and don’t list any parts…I am not sure when Athearn made the last production run.E-bay may be a good bet-even a dummy locomotive will yield the side frames,spare handrails etc.
Vibration = noise, and old Athearns had that in spades. Metal sideframes also means that the loco probably has the cast metal flywheels instead of machined brass. The cast metal flywheels could be out of round and may not be evenly weighted throughout. Machined brass flywheels are much better balanced with less vibration, therefore less noise.
The old gray motors are not as smooth as the newer gold motors. I’d replace that ASAP w/ the brass flywheels. Then there’s the “Jim Six Fix” where one cuts 1/3rd of each motor brush off from the rear of each brush. This eases spring tension on the commutator, reducing the “clogging” noise of the brushes. I’d also apply some 2-26 electrical lubricant (available at Lowe’s) to the commutator with a Q-tip. This will also help smooth out the brush vibration/noise.
Next is the drive shafts. These old Athearns had a sliding sleave with a single key on it. These were also made sloppy. Which means that the single key added an eccentric wiggle to the shaft, and the floppy connections made it worse. Replace these with a “dogbone” style drive shaft.
The other noise maker is the brass worm gear. This should be changed to plastic, hopefully to a nice slippery-type plastic that Kato and Atlas uses.
The gears should also be that nice slippery engineering plastic, but beggars can’t be choosers. The styrene Athearn gears can be out of round. The best way to make the gears quieter without replacing them is to polish them with an abrasive. Clean off all the gears and the gear boxes so they are dry of lubricant. Then apply powdered toothpolish (Pearl Drops) to the gears and reassemble. Run them for a while, then take them apart and clean them off, then re-lube and reassemble. The powdered toothpolish should smooth out the worst of the vibration. Another abrasive option is lapping compou
Paul,As I have mention before a lot of Athearn noise was shell chatter from vibration caused by the way the shell was attached to the frame.Adding stick on weight would cut this chatter way down.
As far as the drive…The biggest problem was the lack of weight like you find in Atlas,Kato and P2K.This is why the “Super Powered” F7 was noticeable quieter then its counter part.
I have removed the shells and have the drive to run quite smooth and quiet.I found the drive shafts was never a real issue as many claim…
There is no real need to upgrade the drive or use the items you listed when stick on weight will do the same.
I am not all that sure that the Six Fix is really needed in some cases…I don’t recommended it for those that may lack the needed skills.
As far as 2-26 elixir approach…I dunno…It does work though…
As rough as they was those old gray jet motors was tough and many can be seen in operation at both clubs still chalking up the miles.