WBB Steamer slows down over time, motor overheats

You either have bad rev unit or bad motor. I would remove the motor run it by itself on DC current see if it gets hot if it does then motor bad probably has shorted windings. I don't know if you can test the rev. unit or not but somebody else may chim in to help to.    

Having the same issue (and a few other issues) on a new J class WBB loco. Will have to call my dealer but would like to know if there are any fixes...motor gets so hot you can't touch it without burning yourself. 

The reverse unit works fine, not sure how that would affect the motor's heat. 

The motor overheating in this manner is a sure sign AC is getting to the motor from the E unit. This happens when the bridge rectifier on the E unit is not heat sinked or under rated for the current required. The fix is an E unit that can handle the load.  These locomotives have a low gear ratio and as such the motor has to "work hard" thus require lots of current. 

What type of failure in a bridge rectifier would cause this? If any one of the four diodes shorted it would look like a diode directly across the track and I suspect that the transformer, or any other load on the same transformer would be affected. I suppose it could be an open diode, but that is not the standard failure mode for semiconductors of this size. I do have another WBB steamer that works just fine, so I sort of doubt a design issue.

I will put a scope on the motor leads and see what it shows. Is this a known issue with the WBB e-unit? 

Which WBB loco do you have?  Yes they have been known to use some poor gear ratios, especially the scale Hudson and repro 726 Berkshire.  The 4-6-0 old timer is geared "right."  Now they need to go back and retool the rest of their product line.

There's an old saying, you can't make a silk purse out of a sow's ear.  So trade in that sow and get yourself some silk!

If you still have the shell off, you could take the motor out, and spin the drivers to see if there is a bind in them. I have run across a couple newer locos that have zinc pest in the drivers, which either tightens up the mechanism or throws the drivers out of quarter, making the motor work harder. Check to see if any drivers are loose on their axles, that would also throw the drivers' quartering off. If it were mine, and I could get a new motor, I would invest in a Dallee reverse unit, a proven product with a company that stands behind their items. Keep us posted. 

Thanks all for the input - this seems like a common Williams Steam issue. I've had this issue before,  friend has and I've seen lots of posts regarding this over the years. 

I've got another issue with my J binding on occasion. I will talk to my dealer tomorrow. This is a good reference. 

PLCProf posted:

What type of failure in a bridge rectifier would cause this? If any one of the four diodes shorted it would look like a diode directly across the track and I suspect that the transformer, or any other load on the same transformer would be affected. I suppose it could be an open diode, but that is not the standard failure mode for semiconductors of this size. I do have another WBB steamer that works just fine, so I sort of doubt a design issue.

I will put a scope on the motor leads and see what it shows. Is this a known issue with the WBB e-unit? 

The Bridge when it overheats will breakdown and pass a low value reverse voltage.  I have seen this first hand, and it is very real and typical of a bridge rectifier.

I have had overheated motors in my Williams PA-1.   Roof got so hot, I'm was concerned it would damage the plastic.   Does this problem and solution apply to Williams diesels as well?  Is the rectifier separte from the e unit or are they one component?  

Is the J a low gear ration or high gear ratio.  While a motor will need to turn faster to attain a set speed when gear ratio is low, I thought less motor torque is required to move the train.  Therefore a High gear ratio causes motor to work harder.  OF course reference matters, and I would call an engine that needs 40 revolutions of the flywheel for one driver revolution a low gear ratio, while one that only needs 20 fw revolutions to 1 driver revolution a high gear ratio.

Not sure if the newer WbB have a different E-unit, but they normally have 2 bridge rectifiers on them rated at 8amps, one is usually heat sinked to the chassis.

Interesting issue.   G

Just spoke to the dealer I bought it from. I will give it back to him and he will send it to a friend of his that used to work for Jerry Williams doing repairs.

I'm having the overheating issues, both on the motor and, what feels like the reverse board (middle of boiler area).

I'm also having issues with the engine occasionally binding up but have not been able to find the source of the actual binding.

I've been 0/4 with Williams steam engines. Hoping this doesn't bump the score to 0/5! FWIW, I'm 2/2 on diesels! Will also print out this thread to include.

Doesn't Williams (old and new?) have lifetime warranties?

Alan

SJC posted:

Just spoke to the dealer I bought it from. I will give it back to him and he will send it to a friend of his that used to work for Jerry Williams doing repairs.

I'm having the overheating issues, both on the motor and, what feels like the reverse board (middle of boiler area).

I'm also having issues with the engine occasionally binding up but have not been able to find the source of the actual binding.

I've been 0/4 with Williams steam engines. Hoping this doesn't bump the score to 0/5! FWIW, I'm 2/2 on diesels! Will also print out this thread to include.

Hi SJC-

Did you ever get this resolved? Did you get a report on the cause? I have one with the identical problems myself.

ajzend posted:

Doesn't Williams (old and new?) have lifetime warranties?

Alan

No.

I always thought that, too, but was surprised when I had some work done on my scale Hudson 9 years ago.

A simple and inexpensive cure to see if the motors are good is to use a bridge rectifier rated at 6 amps 50 volts.

When Bachmann first took over the Williams line they had a batch of bad circuit boards that shipped out in the Williams engines. If you have an older WBB engine see if Bachmann will replace the circuit board for you at no cost, remember the defect is theirs.

Lee Fritz

Yes, it is mostly about getting up the gumption to get started. It's not like I don't have another loco..... 

I have about 12 Williams engines in my collection. So far no circuit boards have failed on me. I have modified a pair of Williams powered F-7 A units(both A units powered) to run on bridge rectifiers, one in forward and one in reverse, they did not start the way I wanted them to so I got rid of the circuit boards.

Lee Fritz

PLCProf posted:

SJC posted:

Just spoke to the dealer I bought it from. I will give it back to him and he will send it to a friend of his that used to work for Jerry Williams doing repairs.

I'm having the overheating issues, both on the motor and, what feels like the reverse board (middle of boiler area).

I'm also having issues with the engine occasionally binding up but have not been able to find the source of the actual binding.

I've been 0/4 with Williams steam engines. Hoping this doesn't bump the score to 0/5! FWIW, I'm 2/2 on diesels! Will also print out this thread to include.

Hi SJC-

Did you ever get this resolved? Did you get a report on the cause? I have one with the identical problems myself.

No, no news yet. Hopefully within the next few weeks.

I'm back....and I got the J back.

Not sure what the tech did to it but it runs great - no binding, smooth, etc.

HOWEVER - the motor still gets blistering hot! The cab roof area, sides, as well as the motor itself get too hot to touch after just a short period of operation. I've lubed it up, no binding confirmed, etc. Granted I'm running on 031 and 042 curves, tight for a big loco but that is what it was designed for.

I'm once again going to send it back to my tech. Any idea on what makes the motor so hot? It doesn't slow down or stop but boy does it get HOT! What is the fix? New motor and/or reverse board? EDIT - I see an older post from Jon at Lionel - sounds like a new reverse board is in order?

Find out what the tech did, but no way the motor should get hot like that.  G

Let's end some of the speculation from earlier in this thread.   I believe this loco has a flywheel visible/accessible in the cab.  Can you please twirl the flywheel with your finger, note the position of the drive rods, and count the number of turns it takes for one revolution of the wheels.

If it's around 12:1 or 13:1 yes it will run hot under load.  It's under-designed and there's nothing you can do except lighten the load.  If it's around 18:1 that's acceptable although I still wouldn't run it slow on a chopped-wave supply for long periods.  Please do this test- it takes 5 min and won't hurt the loco- and report your results here.  Thanks for sharing!

Ted Sowirka posted:

Let's end some of the speculation from earlier in this thread.   I believe this loco has a flywheel visible/accessible in the cab.  Can you please twirl the flywheel with your finger, note the position of the drive rods, and count the number of turns it takes for one revolution of the wheels.

If it's around 12:1 or 13:1 yes it will run hot under load.  It's under-designed and there's nothing you can do except lighten the load.  If it's around 18:1 that's acceptable although I still wouldn't run it slow on a chopped-wave supply for long periods.  Please do this test- it takes 5 min and won't hurt the loco- and report your results here.  Thanks for sharing!

Ted,

Thank you. I will do this later tonight and report back. Thank you.

Well, I started this thread, so I will comment! I sent the loco back to Bachmann, and just got it back today. Mine is the 40505 Berkshire. Report says they lubed the chassis, repaired loose screws and connections on control board and loose screws on motor. Put it on the layout about 20 minutes ago pulling a light load, about 8 PW cars on a level loop. So far, so good.

1. This unit has a ratio of not even 12:1. maybe 10.5 :1 or so between the motor and drivers.

2. The extreme motor heating I was experiencing was not a load issue, part of my original troubleshooting was to run just the loco and tender, and even that caused it to jam, stall and get scorchingly hot.

3. It seems to me that, since it has been returned, the driver axles have much less axial play; the whole driver wheel assembly seems much tighter. It also appears that either the leading or trailing truck or pickup rollers may have been replaced, I see that the drivers are very well oiled, but the first time I ran it I heard the squeal of un-lubed Williams trucks and rollers. Haven't oiled anything yet, want to see how long it will run. Before the return to the shop it would run not more than 5 minutes before it got hot and virtually stopped, if it didn't jam first.

I am not sure exactly what they what they did with this loco, but I am not going to argue with success.

PLCPROF: Thanks for the follow up. Glad your engine seems to be running well. I assume Bachmann didn't give you a breakdown on what was done or go into much detail?

All - Just spun the wheels on my J. Looks like 12 revolutions of the flywheel to get the drivers to spin one revolution (12:1). I should note mine overheats running solo, without train or tender even. 

chessie1971 posted:

You either have bad rev unit or bad motor. I would remove the motor run it by itself on DC current see if it gets hot if it does then motor bad probably has shorted windings. I don't know if you can test the rev. unit or not but somebody else may chim in to help to.    

Hello PLCPROF..........

This is a good advice, I would try that and if the motor is fine then problem is the E-unit. I had one older Williams GP-9 and it had a bad e-unit then was replaced and everything is fine.  Try disconnect the motor from the E-unit and run it on (DC) power such as DC pack for H.O or N scale trains or 9 volt DC battery if the motor runs fine without getting hot then its the e-unit.  If the motor runs hot again on DC power then motor is bad.

Tiffany

And don't forget to lube as part of your investigations!

Just a followup, for those with similar issues.

I have been running this unit for a few days now with no trouble; have had no mechanical jams and the motor heating is within reason. I will agree with Ted Sowirka, however, that the gear ratio is far from optimum, when I run at reasonable track speeds the motor is far, far below its "happy range."

I also have a WBB S-2 turbine somewhere, that seemed to run a lot better, maybe I will dig that out and see what its gear ratio is. It also has much smaller drivers than the Berkshire, so even with the same gearing it should give a better result.