Postwar Buzz Kill

It is an overpriced Full Bridge Rectifier. Running your e-unit solenoid on DC will have the ill effect of magnetizing it.

If your e-unit is very noisy, there are some service tricks you can use to quiet it down (not fully eliminate the noise). You can also replace with an electronic e-unit, but that would be a non starter in my pre/postwar collection.

@bmoran4, what's your personal experience?  I've heard different things about whether operating an e-unit on DC will magnetize it (and how that would affect further operation of the plunger.)  The effect might be worse on straight line (battery) DC, vs. rectified AC as would result from inserting this type of bridge.  And since most demagnetizers work by passing AC current through the ferrous metal, I would think that removing the rectifier should quickly reverse any damage.

For a while in the early 1980s when Lionel was selling all-DC train sets, they offered an accessory to convert existing layouts to DC.  At the time they claimed it would not harm traditional locos, except that the whistles had to be disconnected or they would blow continuously.   Would like to know for sure one way or the other.

I've never had an e-unit that I needed to power with DC. In maintaining my fleet of 100+ locomotives, I've always been able to rebuild them and get them to operate satisfactory on AC.

Here is a video showing the difference in just shaving a bit off of the top of the pawl so it seats properly. Others have reported adjusting the pawl arm achieves the same:

It is theoretically sound that you can demagnetize a magnetized e-unit buy running it on AC again. The coil does run hotter on DC and could potentially be an issue, but I've found no substantiated reports of true damage.

In my opinion, running on DC masks the symptom and doesn't address the cause (something dirty/worn/degraded out of spec) which then magnified by the AC pulses.

 

I like the buzz, and the smell of ozone. I don't like sticky magnetized E-units...

Adjust the angle of the pawl where it contacts the gear and you'll reduce or eliminate the buzz.  Use a pair of needle nose pliers and very slowly readjust.  A teeny-tiny change in the pawl angle is all that's needed - don't overdo it.

Dale

 

@dkdkrd,

Start by familiarizing yourself with the e-unit operation and construction here:

http://olsenstoy.com/searchcd31.htm?itm=1070

 

The pawl is the silver piece moving up and down. On the backside is a hook that catches the E unit drum. You can see at the top on the upstroke it contacts the top of the E unit housing. That's where you would file some material off.

 

Sometimes the directions on here amuse me...generalities, with no specifics, diagrams, or pictures: like getting directions in a rural, and not necessarily rural, area:   "oh, ya wanted get to Boondock?...keep goin' northeast  ninety furlongs, turn right at Herman's,  in fifteen minutes, more or less, ya will come to a fork in the road with two creeks, along roads..follow the creek road to the old Heimerdinger place and turn left just past the barn...another fifteen minutes and you are there" 

 

 

Guys, I cannot begin to thank you all enough...

I had inquired about this here a while back, and out of a reluctance to open up the pride & joy of my meager collection, I was living with the buzz.  Truth be told, I do find it somewhat pleasantly nostalgic in a PW kind of way. 

BMORAN4, after watching your video of the significant change achieved by such an easy fix, I realize it’s time to put on my big boy pants and try this.  It’s also great to see the Olsens site is back up... I need to save these pages tonight. 

PENNSYLOVER- is the best angle for the pawl to contact the gear dead center in the “V” of the gear?  I imagine the minuscule adjustment is to be towards the gear, and not away, which in my mind’s eye could create a buzzing. 

TRAIN NUT- Thanks for your video! This simple video really put a face to the name... Since I’m a first time E unit hack, it’s fantastic to know exactly what I’m after, and where it is. The pictures in the manual got me half way there, but your video drove it home.

 

Tom

 

 

I kill the buzz by locking the engine into forward.  I don't do any switching with my postwar locos, so I don't need neutral or reverse.

Just to straghten some term specifics; the pawl is only the hook portion of the ratchet mech., the moving part within the coil is a plunger. A "bumper" will ease vibration noise on ac and mostly prevent sticking DC because it may eliminate the plunger metal to metal contact to the coil frame. I'd go with a dense rubber dot over foam (inner tube, or countertop anti-slip "legs"(rubber dots) The foam will wear down much faster. (the plunger still vibrates, but not metal against metal). It will also be less likely to foul the the coil guide tube (inner liner) with debris, and less likely to react chemically with a guide tube too. My experinces are more from chasing coil vibrations in pinball flippers, but the basics still apply.

I like the buzz, how can I get my Legacy engines to buzz?

Chris S.

The pawl is connected to a metal rod/plunger which is in a solenoid and when the solenoid is activated it moves the rod up and down when the solenoid is activated / deactivated, in turn pulling the pawl up and down. You can see from the picture there's a rod going through the bottom of the plunger. That rod rides in slots on the side of the E unit casing,  and that's what limits the travel if not making contact with the top.  It also keeps the pawl from dropping too low.

 

Found this ad for Super Unit! Probably early 80s. I still like the old buzz though.

This is what I come to this forum for!!! Thanks all who offered the great tips.

franktrain posted:

Found this ad for Super Unit! Probably early 80s. I still like the old buzz though.

What a great name for a product...

Thanks franktrain for the cheap and easy trestle solution as well!

FlyPlanes-PlayTrains posted:

Thanks franktrain for the cheap and easy trestle solution as well!

Fly-Planes Play-Trains,

That looks good. I took my elevated dual track down and want replace it with single track like yours.

franktrain 

FireOne posted:

I like the buzz, how can I get my Legacy engines to buzz?

Chris S.

I'm not sure if this is a joke or not. Folks tend to lean one way or another and mostly Legacy and mods don't appear on the same pages together..be it price or nature of the beast I've no clue, but....

   Wire one to the rollers. It doesn't really have to do anything but click and or buzz.  In fact, you might find a cheaper relay since it is really just a post war sound effect here.

   LOL, do you think in twenty years the new Legacy Post War Classic sound file might contain a buzzy e-unit clicking away? 🤣

 It would make for great Easter Egg gag anyhow. (a hidden file or feature)

If you wanted to increase the buzz of a quite one ad a single diode. It will result in a pulsed dc at 60hz.

  Adding a cap might keep one from dropping out on bumps,etc. too; but also causes a need to wait a second at 0v for the click of the drop out to happen as the cap still delays it there too.)

Adriatic, if you're adding a single diode and then perhaps a cap, you're on your way to giving pulsed DC to the e-unit.  I don't know if that setup will magnetize the plunger and pawl as quickly as pure DC, but you're headed in that general direction.

Dale

Yea, I know. I was more addressing the offshoot of adding an e unit to legacy and just thought it funny...and do-able, lol. It slipped my mind while typing. Good call.

Adriatic posted:

FireOne posted:

I like the buzz, how can I get my Legacy engines to buzz?

Chris S.

I'm not sure if this is a joke or not. Folks tend to lean one way or another and mostly Legacy and mods don't appear on the same pages together..be it price or nature of the beast I've no clue, but....

   Wire one to the rollers. It doesn't really have to do anything but click and or buzz.  In fact, you might find a cheaper relay since it is really just a post war sound effect here.

   LOL, do you think in twenty years the new Legacy Post War Classic sound file might contain a buzzy e-unit clicking away? 🤣

 It would make for great Easter Egg gag anyhow. (a hidden file or feature)

Adriatic, I posted that in jest, I do like the buzz though. Fun to see others thoughts on it though.

Chris S.

I figured The answer was just so simple; the thoughts so funny... I had to answer.

Very interesting discussion and solution for the e-unit buzz. I'll have to give it a try on some of the loudest buzzers in my fleet.  On a related matter, E-units will magnetize even when run only on ac. I had a couple that did that and there is a simple fix for that too. My in-law who repairs trains for a living, said to just get some extra plungers and swap the plunger in the e-unit that is sticking (magnetized). I did that and it appears to solve the problem. If you go this route, make sure you use the correct plunger. There are a couple of different types. One has a dimple on top, and the other doesn't. So make sure your replacement plunger is exactly the same as the one originally in the E-unit.

Ken