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Ho 70 ton 3 truck climax motor ptoblems

Started by Gearedenginefreak, December 14, 2018, 02:03:44 AM

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Gearedenginefreak

Hi, I have a newish 70 ton 3 truck climax. It has less than 2 hours runtime. It suddenly stopped running. Motor not running... I have heard of the split gear problems and so trying to track it down. I have actually disconnected all 3 trucks from the main gearbox to see if the motor will run. The rods and pistons on the sides will run about 1/2 second and then seize up and not run. I removed the decoder and jumpered a 3 volt battery pack to the motor pins on the 8 pin socket. It will run for a while and seize up. Again, this is with no trucks or their associated gearing connected. So its just the motor to the siderods.  I began to think there might be an issue with the circuit board - newer style with mostly smd electronics. So I cut out the board and soldered in an 8 pin socket to eleminate board issues. This did not change anything. So I am now at a loss of what is next. Motor? Is there a capacitor directly on the motor itself that should be cut out? Is it possibly gearing in the main gearbox? How should I proceed and is the motor easy to get to without complete dis-assembly of all the bits and pieces?
Please help. Thank you.

WoundedBear

My experiences with the Climax models would have me looking for a split gear in the gear tower.

Problem is getting to the gear tower. The entire loco needs to be dismantled to gain access. Bachmann won't go into the gear tower either.

All I can say is good luck. If you are mechanically skilled, have a go at it yourself. If not, maybe Bachmann Service will replace it for you, for a nominal fee.

Sid

Gearedenginefreak

Sid, Thanks for that. I am mechanically inclined so will probably have a go at it.
More info, I discovered if I use just a 3 volt battery it will run the motor and side rods without the trucks for many minutes. Never actually got to a point where it would stop. Albeit slow.  But if I put a new 9 volt battery on it, it runs a few seconds (and faster) and then seizes up.
I suppose this could still be a gear that at slower revolutions does okay. But now I am also suspecting motor windings. I have read some accounts lately of motor windings causing issues as the motor heats up. It isnt running long enough to heat up per se, but more voltage is more heat, so considering that too.
If anyone can add their experience to this, I am all ears.
Thanks.

rich1998

I would agree with WoundedBear. I have belonged to a number of train forums for a few years and have seen many discussions about HO and On30 Bachmann geared locos like this developing cracked gears. Some right out of the box new.
One fellow in the MRH forums a couple years ago measured a few locos and found the metal shafts were just fine. The gears are formed in a plastic molding machine and there issue develops. The I.D.'s are apparently slightly different. Some a little too small. A fracture develops over time.
Look carefully at the gears. Bachmann motors are usually just fine unless abused.
Most locos, the plastic gears are made this way.
NWSL makes their plastic gears by machine. They also make steel gears. No idea if they still make gears for Bachmann locos but Bachmann has been making replacement gears.
Good luck.

Rich

Gearedenginefreak

Progress update on my 3 truck HO climax issues.
I disassembled the model to get to the motor and gear tower. I found an excellent blog site with great directions and photos on getting it apart.
Here is the link to that...
http://gearedsteam.blogspot.com/2017/12/bachmann-ho-scale-climax-disassembly.html?m=1

I took the gear tower apart and could not find any split gears. I examined all the gear assemblies in the trucks and the cylinder drive gears. No issues.
So I tested the motor with it completely disengaged from the gears, just free spinning. I jumpered a 3 volt battery pack (2 aa's) to the 8 pin decoder socket on the motor leads with no decoder.  It ran fine and continuously. I then changed to a 9 volt battery and within seconds of starting to run, it slowed and stopped. So, I either have a circuit board problem at the board that is mounted on top of the motor, or the motor is bad per my first assumption in my original post.
I have looked at the Bachmann parts pages trying to locate both the circuit board and the motor. No such luck. This loco is not very old. I don't understand why there would not be parts available.
In fact the parts for this loco are very few.
If anyone has any suggestions or thoughts on where I can obtain those items, it would be much appreciated.
Otherwise I have a very expensive shelf decoration. I have less than 2 hours run time in this locomotive.

Tom

rich1998

To my knowledge the motor are 12 volt motors with some caps and a couple inductors because of the decoders that use DCC. All my other Bachmann locos came like that. Those components did not affect the motor. Good chance the motor is bad. I would put the loco back together and contact the service department for possible repair.
I just looked at the photo of the motor and PC board but it did look different but could not pick out the components.
Did Geared Steam comment on your issue about the motor slowing down? That is strange.

Rich

Gearedenginefreak

Rich, it is a very small motor. I had no idea it was that small. The board on the motor gear cover has 2 big resistors, a couple of tiny smd items - maybe capacitors and what looked to be a disk capacitor. I briefly bypassed the circuit board and put the 9 volt transistor battery directly to the motor leads. It smoked from the motor. I mean it was maybe 2 seconds. So, I think the motor is not a 12 volt motor but rather maybe 6?  And the big resistors are functioning as drop down resistors. At least that is my theory with no facts to back it up. If the motor is 12 volt, I think the smoke may confirm bad windings in the motor.  Anyway, I really just want to replace the motor and that one circuit board.  If I could find the items needed..
But, as always, open to advice from anyone who has it to offer.

Thanks,
Tom

rich1998

What looks like resistors are usually 4.7 microhenry ferrite inductors. The caps are sometimes yellow blobs. I think 0.1 microfarad bypass caps. They form a tuned circuit. Required by the UK and EU because Bachmann sells a lot over the other side of the Pond. Many think those green things are resistors and replace them with a piece of wire. Check the color code. Google the color code. Easy.  I have also measured them with an inductance meter. I use to make tuned circuits many years ago making filter circuits for short wave. Inductors are zero resistance.
Some are wire wound inductors.
Some PC boards have surface mount caps. The components usually have an I.D. C, L, R. that shows what they are. Most never pay attention to the Prefix.

Rich

Gearedenginefreak

Rich,
when I was doing all that troubleshooting the other day, I actually clipped on leg of what I thought was the cap - the yellow blob. (Some of the recommended motor performance tips say to cut the cap that goes across the motor leads whether diirectly or in a circuit). I have done that succesfully with several other Bachmann locos . But in this case, it prevented the motor from working at all.  I will check those resistor looking things. I know about the inductors, but these did not look like the ones I have seen before.  The smd devices if my memory is correct had a 'C' by them.

By the way, when testing before I clipped that 'Cap',  testing with a 9 volt transistor radio battery to 8 pin plug on motor leads only.. that yellow blob got so hot to the touch it burned the tip of my finger when I touched it. This might be a clue as to what is wrong with the motor?

I will try to take a clear close up photo of that small citcuit board and motor and post it here. Hopefully tomorrow.

Thanks again for your input, Tom

rich1998

Well it sounds like you have some knowledge of electrical components. The photo of the motor and PC board assembly was not clear.
A clear photo of the PC board might help. It sure sounds different. Bachmann does change canoes in the middle of the stream at times with components.
IBachmann does replace defective locos. They did for me.

Rich

Gearedenginefreak

Rich,
In a previous life I repaired computerized cash register systems for a living. Replaced defective components  in a lot of NCR restaurant point of sale stuff.  That was a long time ago though and I certainly dont know everything I would like to. The micro components in our trains are a total wonder to me, but I sure love to figure out problems.
I wonder if Bachmann would even consider my unit. It is in many pieces now as I try to find parts for it. And I kind of cut up their circuitry a bit. But I may give them a call just to see what they say.

Gearedenginefreak

Rich,
I finally was able to get some photos of that motor and pcb attached to the motor. I just dont know how to attach them. I would be glad to send them to you offlist? 
The motor measures 10mm (flat side) × 12 mm (round side) × 15.5 mm length. Plus 1 mm diameter shafts out both ends at approx 8 mm length- 1 end has a flywheel and the other has the worm.

Thanks, Tom

Gearedenginefreak

Update... my good news of the day is that after having measured this motor, I have found a replacement of exactly the same size. Northwest Shortline has one and it is even 12 volt. (I think the Bachmann motor was probably less voltage and used circuitry to drop the voltage to their needs - there are markings on the motor that cause me to think it may be a 6 volt motor. At least that is my theory of why my motor failed). I am going to order it this week. Then when it comes in, I will move the worm and flywheel from the old motor to the new motor.
I am also going to remove the Bachmann circuit board that was on top of and only connected to the motor.
Then I will reassemble all the pieces. I think I will also replace as much of the plastic gearing as I can with metal gears.  Bachmann has some and Northwest Shortline has some. 
I will keep posting with updates as I can. I hope to have this fine looking locomotive back to running by the end of the month.

Tom

rich1998

Great troubleshooting.
Bachmann might have put in a lower voltage motor. No idea. From what you said, there are more components on the PC board than just caps and inductors, the two green things.

You have to use a photo hosting site like Photo Bucket. There are a couple other sites that do this.
You join the site, upload the photos. Then select the photo and link it to whatever forum you belong to. You might have to resize the photo a little smaller.
Look down to the General Questions forum for posting pictures with Photo Bucket. Most never look there.

NWSL has always been a great help for me.

I thought more would help here.
Good luck.

What you are doing might help some in the future. Try to document and keep good photos.

Rich

Gearedenginefreak

Rich,
I will look into photo bucket or something and let you know when photos are up. Not a priority for tonight.
I wish I had taken photos during dis assembly. Not only to help others but to remind myself.  I kind of kept stuff in groupings. That other site where I found some great tips will help me get it back together. I was just on a mission and should have slowed down to document.  Lesson learned.

Thanks for your encouragement.

Tom