Diesel 7720 train questions

[jimim]

I pulled out my old train the other day so my son and I can add it to his small setup. 

 

I have a few issues. 

 

1.  The rubber around the wheels which are attached to the motor are all dry rotted.  So I have no grab. 

Is it possible to add a new motor or base setup so I can build the engine that it came with still?   I will buy whatever I need. 

2.  The other problem is I have zero magnets that Acted as the couplers for each piece  I still have the actual black pieces they attach to though.  So can I replace this whole piece with new ones  if so can I buy these easily.

 

sorry if these r pretty rookie questions  I'm just trying to wrap my head around all of this.

 

thanks a lot,

jim

 

 

[Heppeng]

1. Replacement rubber is easily available on ebay or bricklink. If you are struggling you can also use bicycle inner tube - get the thinnest racing bike type and slice them up. One tube will give you a lifetime supply!

It is possible to use any motor in this train, they are all backwards compatible. However the newer battery powered ones use a different voltage and will need a different wagon for the batteries.

2. Magnets - replacement again best bet is bricklink or ebay.

[Dan-147]

7720 was my favorite train from the 80's.  Of course, the fact that LEGO did not sell 12-volt trains in North America at the time limited the choice of trains.  I still have mine in all it's 4,5-volt glory, including the original motor.

As it is, it works directly with the newer trains as the track gauge is the same and the magnetic couplers are functionally the same (the separate magnets were eliminated and integrated into the buffer beam following an issue with a child swallowing magnets from a different toy company).  The separate magnets are now rarer and therefore pricier but the newer buffer beam is a direct swap for the your buffer beam, magnet holder and magnet and it might actually be cheaper.  As for the motor, that old clunker actually has more torque than recent train motors and there's more capacity (for longer running) in those old C-cells than in AA or AAA cells.  I've been told that the 9-volt Power-Functions IR receiver that drives recent trains might actually work at 4,5-volts if you want remote control; although I haven't gotten around to trying it for myself.

Whatever you decide, 7720 is a great set and I hope you have fun with it.

Dan-147

 

 

Edited October 29, 2016 by Dan-147

[patje]

I have this for sale
for a reasonable price

they are not the real

http://users.telenet.be/Patricks-legotreinensite/treinbandjes.htm

[jimim]

2 hours ago, Dan-147 said:

7720 was my favorite train from the 80's.  Of course, the fact that LEGO did not sell 12-volt trains in North America at the time limited the choice of trains.  I still have mine in all it's 4,5-volt glory, including the original motor.

As it is, it works directly with the newer trains as the track gauge is the same and the magnetic couplers are functionally the same (the separate magnets were eliminated and integrated into the buffer beam following an issue with a child swallowing magnets from a different toy company).  The separate magnets are now rarer and therefore pricier but the newer buffer beam is a direct swap for the your buffer beam, magnet holder and magnet and it might actually be cheaper.  As for the motor, that old clunker actually has more torque than recent train motors and there's more capacity (for longer running) in those old C-cells than in AA or AAA cells.  I've been told that the 9-volt Power-Functions IR receiver that drives recent trains might actually work at 4,5-volts if you want remote control; although I haven't gotten around to trying it for myself.

Whatever you decide, 7720 is a great set and I hope you have fun with it.

Dan-147

 

Thanks guys.

So I can take the couplers from the new trains and just use them on the old train.  We didn't start the train yet.  He is "earning it" but doing work each day with my mom after pre school. If so that would make the most sense for me then cause I can get those easily and I can use my old cars on a new engine.

 

Regarding the motor.  SO lets say I don't want to use the c battery train tender.  Can I build the engine out and ad in a new motor that is from today.  The IR one.  Is there anywhere on the net I can look to pretty much make a new base with wheels and build the engine onto that? That way I can just loose the old motor and wheels and start fresh with updated pieces.

 

Ya it would be nice to have the whole set intact but if I can remote control it that would be even better

Thanks again,

jim

I just look at the pieces and manual for the blue train we bought. It has the rear 4 wheel motor.  can i build that along with the ir emitter into the red diesel train I have.  seems to be similar size.  Then maybe build the battery pack into the tender or make a new tender for it? would this newer motor size up well with the old motor?

 

jim

[Dan-147]

The old train motor is actually bigger than the newer one (height mostly) so it is rather easy to swap in the newer motor.  It might be harder to put the IR receiver in the loco without changing it's look.  However, if you're going to make a tender car for the battery pack, you could install the IR receiver there, next to the batteries.  The wire from the motor is long enough to reach the IR receiver even if it is in the next car.

Dan-147

[jimim]

19 hours ago, Dan-147 said:

The old train motor is actually bigger than the newer one (height mostly) so it is rather easy to swap in the newer motor.  It might be harder to put the IR receiver in the loco without changing it's look.  However, if you're going to make a tender car for the battery pack, you could install the IR receiver there, next to the batteries.  The wire from the motor is long enough to reach the IR receiver even if it is in the next car.

Dan-147

hey dan.  totally fits!  yes i have to put the IR and the battery pack in the rear.  I'm going to make a tender for them.  I just have to find something easy online. :)

 

my mother, out of nowhere, found 6 of the 8 magnets for my couplers!  how wacky is that.  they were in a sewing box of hers.  no idea.  so i found a set of old one s on eBay.

oh and my old motor actually works, but i think i would rather have it remote controlled for him so i'm going that route.  

 

so now all i need, and maybe you can help me out, is what the namer part number for the old base with the couplers or even the version without couplers so i can build him 2 other engines from old parts. i'm going to build the other black one that was in the instruction manual for the set.

 

here is a pic of the part. oh and of the train together.  i wish i could put together 1 or 2 more of the passenger cars, but finding the doors would prob be really hard.

Untitled by Jim, on Flickr

 

Untitled by Jim, on Flickr

 

was fun bringing the set back to life.  its in great shape.  grey bricks are kinda worn, but not bad at all!

thanks for all the help!

jim