'84 electric Marathon rebuild question

[Gonkulor]

rlw welcome to BGW Marathon brother from a different mother

Originally Posted by rlw

I just picked up an '84 Marathon for $290. It's going to be a winter project. Amazingly, the thing runs, but not very well. I've been lurking on this forum for a couple of weeks, and it's been a treat reading the rebuild threads.

Is it possible to replace a resistor controller with a TXT controller and keep the stock Marathon DC motor? From perusing this forum I think the Marathon's motor is a "series" motor. Am I wrong?

I realize I'd have to also install a potentiometer-based accelerator to replace the wiper board.

RLW

I'm not entirely sure about the specific controller, but it's all very doable. It reads to me that you have all the "tools" available for accomplishing your winter project. Have fun with it and take lots of pictures

Originally Posted by JohnnieB

3. It's the Wullenweber (circularly disposed antenna array aka Elephant Cage) part of the AN/FLR-9V that used to be at RAF Chicksands, UK. To give you a size perspective, the visible array alone covered 37 acres. I didn't work on the physical antennae, instead I babysat a couple million transistors, a few ICs and Tubes in the round building in the middle and the OPS building about a mile away. (Yes, I can read a schematic )

JohnnieB, Sweet Avatar. I've wanted to comment on it since the day I saw your first response, but I'd never been in an active thread after one of your explanations. So.. Please don't take this wrongly or personal. From my first glimps of your avatar picture I thought "Electric Stonehenge". Then when you say Tubes? It's kinda true. You were a Geek before being a Geek was cool Only thing missing is a tesla coil. I have the utmost respect for your knowledge and wisdom so please don't take those comments wrong. I don't know, maybe I'm repeating stuff you have heard a hundred times?

Now that I got that out of my bucket Back to topic.

rlw does your carts throttle linkage already look like this?


If so I'm going to agree with JohnnieB that you wanna install the ITS assembly under the floor.


It is sounding as your close to leaping at teardown, if you haven't already. If your throttle linkage doesn't look like picture #1 how different is it?

Best Regards
Gonk

[JohnnieB]

Originally Posted by madoc1

johnie, i was ctm and worked at a ww site in winter harbor, me. in 68. b-4 that was in cuba.

cmt? You got me with that TLA (Three Letter Acronym), must be a swabby term.

I've been to Winter Harbor, and just about every FLR-9 and FRD-10 site, as well as many of the FRD-13/AX-16/Pusher sites. (USAF 63-75/USAFSS 69-73)
I wrote a paper (that I am no longer cleared to read) on DFI (Direction Finding Interferometer) and ended up on a team testing and tweaking DFG (Direction Finding Goniometer) beam forming networks, which is an entirely different animal than DFI, but I enjoyed the project and learned a lot.

I also passed through Gitmo a couple time on trips to and from South America while I was in 3MCG. Did stay long, only a few hours, but long enough to know why you used the

[scottyb]

You might be disappointed in the end results of installing a TXT stock drive system in the Marathon. It is quite easily doable with either throttle.
The problem being there is a considerable weight difference between the 2 carts.
When Ezgo engineers began designing a Solid State drive system they used 350 and 400 amp speed controls. Obviously peak would be higher and sustained output would be quite a bit lower than rated.
The lighter TXT carts were fitted with 275 amp controls.
The resistor coil cart has no limit on the amp draw. so you have to be careful not to choke it off too low. And end up with a gutless cart.
In my opinion stay away from stock controls and lightly built NPX controls, spend a little more to get something in the 400 -500 amp range. Increase the voltage to 48v if you can. Hope this helps & good luck with the project.

[madoc1]

johnnie, cmt= communication tech-maintence. basicly electronic tech with a clearance. haven't heard the word goniometer since i left the service. we just tracked russian subs up in maine. that was a beautiful spot. hdq bldg was the old roosevelt estate in the middle of acadia natl. park.

[JohnnieB]

Originally Posted by Gonkulor

...............JohnnieB, Sweet Avatar. I've wanted to comment on it since the day I saw your first response, but I'd never been in an active thread after one of your explanations. So.. Please don't take this wrongly or personal. From my first glimps of your avatar picture I thought "Electric Stonehenge". Then when you say Tubes? It's kinda true. You were a Geek before being a Geek was cool Only thing missing is a tesla coil. I have the utmost respect for your knowledge and wisdom so please don't take those comments wrong. I don't know, maybe I'm repeating stuff you have heard a hundred times?

Now that I got that out of my bucket Back to topic................

I've been a geek all my life and am not the least bit offended by the modern meaning of term. (Etymologically, it meant fool or freak before about 1952, when I was 9.)
In fact, I knew what a "Gonkulator" was without looking it up.
As a preteen, I drove my dad a little crazy every now and then by taking things apart, but he kept his cool most of the time since they worked when I put them back together. Usually worked that is.

There was something akin to a Tesla Coil a few miles down the road at Orforness in Sulffok, a FPS-95 (Over the Horizon Radar - part of Cobra Mist)
They switched 10 MegaWatts of RF at HF frequencies between antenna arrays and if the timing was off, the resultant noise and sparks were spectacular.
I got to visit the place because it was basically a DFI on steroids.

FWIW: I have an stereo preamp and a pair of power amps with tubes in them and I have a VTVM (Vacuum Tube Volt Meter). I don't use the TS-505 anymore since a dimestore DVM is more accurate and easier to use, not to mention, 10 pounds lighter, but I fire up the Dyna PAS-3 preamp and the McIntosh MK-30s when I want to listen to vinyl records the way they were meant to be heard.

[JohnnieB]

Back on topic

Scotty has probably forgotten more about carts than I'll ever know, so I defer to his sage advice. However, I would like to toss in a little food for thought.

Consider building a "Whimpmobile" at minimal cost to get the mechanical and electrical issues sorted out, keeping in mind that you will be upgrading to a 400-500A (or more) controller, solenoid and F/R Switch when the budget allows.

Example: The high current cables probably need to be replaced, so go with 4Ga (at least) and you'll be ready for a higher power system in the future.

Now I've gotta find my tinfoil hat to keep the lighten bolts from So. Cal. from scrambling the few working brains cells I have left.

[Gonkulor]

Originally Posted by JohnnieB

I've been a geek all my life and am not the least bit offended by the modern meaning of term. (Etymologically, it meant fool or freak before about 1952, when I was 9.)
In fact, I knew what a "Gonkulator" was without looking it up.
As a preteen, I drove my dad a little crazy every now and then by taking things apart, but he kept his cool most of the time since they worked when I put the back together. Usually worked that is.

Look up Gonk in the urban dictionary. The variation is not the intention with Gonkulator but moderatly hits closer to RL as l get older, and I as well not offended. Well not offended by most of the meanings someone invented. lol

Sorry rlw, back to topic

I'm going to make an assumption your going to be using your cart just to toodle around your property and visit the neighbors vs. getting in a car to drive a mile. Gotta love a carts ability for stuff like that, somewhat of a motorcycle experiance with the ability to bring along people. Ya get to smell the roses and feel the wind in your face.

We prolly all want more power and torque but is 10mph ok? if so then just above stock is likely fine. I understand now ScottyB's regards to stock and NPX equipment. Your first decision now should be Pot or ITS. I would go ITS because it is Solid State. That decision is going to make your future path. Divide and Conquer.

OK FINALLY; I'll stop today's rambling in this thread. Darn powder coating of my frame isn't done yet! Was supposed to be done last Friday!

[rlw]

Wow!

Great stories. @Gonk - haven't looked under the floorboard yet. Pushing the accelerator with the seat up, I can see the linkage that wipes the wiper board move. I haven't pulled up the mat to see if there's an access hatch there. I was diggin' around in the parts manual (89-91 Electric and 2 cycle... I think I downloaded it from this site) and looked at the exploded drawing of the solid-state controller - pot based, I think. That's kind of what I was leaning towards.

@ScottyB - thanks for the sage advice - I've seen quite a few posts of yours and know you know your stuff. Mainly, I want (like Gonk says) to toodle around my and my neighbor's property. Lift kits, high torque, etc., aren't really where I want to go with this. Mostly it's a cart for yard work, and driving over to my neighbor's pond house sober and back slightly buzzed (through fields and woods, no road driving ). I'm thinking that a controller retrofit would at least be better than the wiper/resistor setup it has now. Who knows? I might be able to increase the budget and go with a better controller, I was just looking for the cheapest way to make this a little better.

@JohnnieB - Point Pleasant!? Watch out for the Mothman and the ghost of Chief Logan! ...Or was it Cornstalk that died there - yeah, I think so, 'cuz Logan hightailed it to Circleville and negotiated the treaty under the Logan Elm.

I wasn't IN the military, but my first away-from-home job was as field service engineer on a room-filling Burroughs B3500 mainframe at an Air Force base in Ohio (that's how I temporarily ended up here). My future (at the time) wife was an E-1 computer operator on that machine. It had ALL kinds of electro-mechanical stuff in the card reader, printer, tape drives (big, refrigerator sized tape drives). That's why I'm comfortable with tearing down this Marathon.

The radio stuff you guys were kicking around also intrigues me - I was a ham radio operator as a high-school kid - build my own CW XMTRs (6L6 beam power tube, a whopping .000005 megaWatts!).

I'll try to take a look at under the mat and see if there's an access hatch there.

Thanks for all the replies!

RLW

[scottyb]

Whatever throttle position sending device you choose, remember none of them do well in wet conditions. Have fun with it... I know sometimes the fun is in see how little you can have into the thing .... but thru the woods requires more power than down the road assuming all inclines are the same and the footing is looser off roads.
I just saw a like new 700 series control sell for $325 in the sale section.... keep checking it for more bargains.
I have no doubt you will be successful in your project

[rlw]

@Scottieb,

There's a ravine with steep inclines (15-20%) on the path from my place to the pond house. With the batteries I have now (3 pretty good, 3 pretty bad), we managed to crawl up (both out and back) at about walking speed with the throttle fully depressed. We had my lovely wife (at a whopping 115 lbs), my goofy dog (at about 55 lbs), the charger (25 lbs - didn't know if I'd need to recharge before returning), and me at about 1/10 of a ton in the cart for a total of about 400 lbs of cargo. I'd like to be able to get up those hills at a little faster pace.

I *hope* I'm successful at this project. I certainly appreciate the ability to pick your guys' brains through this forum.

RLW