Weird Accelerator Issue

[TomBuggy]

Just floor it, right?

You'd hope. The thing is, if you push the accelerator all the way to the floor on my cart, it barely moves. Or, this morning, just doesn't move.

Here's the weird part: if you push really hard on the (already floored) accelerator pedal, it gets more power and starts moving fast. Press even harder and it will still get up to its top speed of about 35 mph. At that point, if you quit pressing hard and just hold the pedal to the floor, it continues speeding along.

The cart is a 20 year old six seater but it has been modified by the previous owner and by me. It looks like this:

That pic is from April and the back seat is off because I had just installed a 48 volt lithium battery. It was at about that time that the accelerator started acting weird.

The accelerator sensor box under the pedal looks like this:

And has wires coming out the back that look like this:

I can't see a label anywhere on it. The cart has a motor and controller package from Hi Performance Electric Vehicle Systems, installed by the previous owner. The controller is a Curtis model 1238-5601.

This is the battery that I got from Lithium Battery Power in St. Pete, FL

It has been working fine for me. Yesterday the cart seemed weak and it was down to 50.5 volts but I charged it back up to 57.9.

This morning it's still at 55.4 volts so should have plenty of power but even if I floor it really hard it just lurches a bit but doesn't move. I got it started rolling by kicking with my foot but I'm not Fred Flintstone!

Do I need to replace that little black box under the accelerator pedal? If so, what would I order? If not, what should I do?

 

[Zman]

What does it do if you just drive it normal? I mean don't punch it just accelerate normally?

 

[TomBuggy]

What does it do if you just drive it normal? I mean don't punch it just accelerate normally?

It doesn't generally move unless the pedal is all the way to the floor. Sometimes it will go with less, mostly in reverse. The problem is kind of intermittent but getting worse.

It has been usable just because I can press harder and get more power but that trick seems to be needed more often and now isn't working reliably.

 

[Tom47]

That's definitely a speed control and it, the linkage, or the wiring is definitely your problem.

What is the serial number of the cart? It is difficult to narrow the part down without more information.

 

[TomBuggy]

That's definitely a speed control and it, the linkage, or the wiring is definitely your problem.

What is the serial number of the cart? It is difficult to narrow the part down without more information.

I took a picture of the serial number plate. It's K0111 - 996948.

The thing is, I know the motor and the Curtis controller are not original and I really don't think this cart has a lot of original parts other than the frame and fiberglass. I'm not sure if the part in question is original, came with the speed package, or is just something someone else put on over the years.

 

[Tom47]

Your cart is a 2001 made in the 11th week. It is one of the last ones made that use that speed control.

That speed control is called a Pot-Box. It is original for that cart, but is no longer available. You will need to replace it which involves removing the foot pedal linkage and the old pot-box. Reinstall the pedal linkage and use this kit to replace it with a new MCOR4:

AM293201 - DS Pre-MCOR to MCOR4 Conversion Kit | Revolution Golf Cars

www.revolutiongolfcars.com

This kit is available for less money if you search around the internet. I'm not sure if any sponsors carry them.

 

[Diode]

Holy crap that's expensive I would look at a pb6 made by Curtis and see if you can get a cable to run off of your throttle to the pb6 probably less than $100. Or pull that throttle box off let's see what's inside of it maybe we can rebuild it

 

[Tom47]

Holy crap that's expensive I would look at a pb6 made by Curtis and see if you can get a cable to run off of your throttle to the pb6 probably less than $100. Or pull that throttle box off let's see what's inside of it maybe we can rebuild it

You got that right! And the replacement MCORs are just as unreliable as the old pot-box.

If you had a V-Glide, a PB6 can use the same linkage with some modification. But the pot-box is a different animal. It take a half hour just to remove it.

 

[TomBuggy]

Thanks for your attempts to help me.

Holy crap that's expensive I would look at a pb6 made by Curtis and see if you can get a cable to run off of your throttle to the pb6 probably less than $100. Or pull that throttle box off let's see what's inside of it maybe we can rebuild it

The problem is that I'm so unfamiliar that I don't know what a PB6 is nor whether you're talking about a mechanical cable or an electrical one.

The other problem is that I looked at the linkage and can't figure out how to remove it. There's a part that appears to me to be a flattened rivet that would need to be drilled out, if I could fit a drill in there. I must be wrong. Right? Please tell me there's no drilling out of flattened rivets involved.

I'll spend a few hundred bucks without blinking. This cart went into the five figure price range when I added the lithium battery. Having spent that much already, I'll spend/do whatever to make the accelerator pedal work. I'd rather spend under a hundred but "install this kit" sounds easier than "see if you can get some kind of cable to work." Doesn't sound easy. Sounds easier. I'm not a mechanic. When I open up Tom's Metal Shop, I usually wind up frustrated and bleeding. I just don't want to wait in line at the cart shop or I'd happily pay them to do it.

 

[TomBuggy]

You got that right! And the replacement MCORs are just as unreliable as the old pot-box.

It seems to have lasted 21 years. That's longer than I'm likely to be around, or at least longer than I'm likely to be interested in this cart.

 

[Diode]

You have had that cart for 21 years you bought it brand new

 

[TomBuggy]

Your cart is a 2001 made in the 11th week.

You have had that cart for 21 years you bought it brand new

No, I just bought it last year. Tom47 says the part that failed is that old.

And it isn't really done failing. Yesterday I had it out doing chores and after a while of stop/go and low speed use, it just wouldn't move. Recalling that it seemed awfully peppy when I started out, I just got out and let it rest a while. Sure enough, got back in and got it to move.

Got it to move by almost reopening a hernia that a surgeon closed earlier this year. I'm too old to have to put all my weight and strength into bending an accelerator pedal so my cart will move. Whether with a Pot Box kit or a PB6 or whatever other solution may exist, I've got to get this thing acting normal again.

 

[Tom47]

Unfortunately, I have never removed a pot box nor installed a PB6 on the pedal linkage. I won't be much further help with this.

Possibly a sponsor here can help you with the particular details of doing this repair.

Wishing you the best on finding a solution.

 

[TomBuggy]

Thanks for your input. I think I'll give the local shop a crack at this problem. I'm not at all confident I can get the pedal linkages apart and back together.

 

[Tom47]

That's probably your best option at this point. I hope they don't overcharge you for this. If they can adapt a PB6 or an electronic foot pedal, it shouldn't break the bank!

 

[TomBuggy]

Well, that plan failed. The cart shop said they'd seen something like this before and the conversion kit was slow and hard to find and then required major disassembly and drilling/cutting of frame parts to fit. They said the labor part of the bill quickly ran to $1,000 and the customer wasn't happy. They refused to work on my cart. I asked if anyone else might work on it and they mentioned a shop an hour away. So maybe I'll call them or maybe I'll just figure out how to do whatever they did that cost a grand before. I'd happily pay if someone would take my money. If no one will, I can't just throw this cart away and I can't sell it if it doesn't work, so I guess I have to learn to fix it.

 

[Tom47]

You are going to need help from an authorized Club Car Dealer for this and it won't be cheap. Here is a link to help you find one: Find an Authorized Dealer | Golf Carts and UTVs | Club Car

That won't be cheap as they will use the high priced MCOR4 kit to repair it. But your exceptional cart with the lithium battery is worth a lot. If you have $5000 invested at this point, adding another $1000 will be well within reason and value. You will have a cart worth $8000 around here.

I have over $5000 invested in mine as shown, and although I couldn't get more than $3000 for it as is, it is priceless to me.

 

[TomBuggy]

I wish I only had $5k in this one. Actually, I wish I only had $10k in it. But it's more.

I've already done that math and the most it makes sense to me to spend on this issue is about $8k.

If someone would take my money. There is a dealer about an hour away. I used to work at a dealership. Different industry, but I bet the lines are the same. "Sure, we'll work on the Club Car parts. Wait, you want us to connect them to that weird controller and motor? Nope. Buy a Club Car controller and motor."

And that might be how the price gets up near my limit. I'll call them when businesses open and ask but I expect to have it pretty well disassembled by then anyway. I'm used to this. I live in the sticks and manufacturers quit making whatever I like, so I learn to fabricate it myself. I'm not good at it, but I'm my only available choice.

 

[cartmaster]

Wait a minute. I just saw this thread. I looked at this picture and have a question. The bolt head I can see bang in the middle of the image looks to be contacting on top of the damper/spring arm. If it is, it would restrict movement of the operating cam for the pot box. Can you confirm if this passes the damper or comes up against it. I wonder what it does? is it a throttle pedal limiter and has it slipped down to the bottom of the slot?

 

[TomBuggy]

Wait a minute. I just saw this thread. I looked at this picture and have a question.View attachment 10263 The bolt head I can see bang in the middle of the image looks to be contacting on top of the damper/spring arm. If it is, it would restrict movement of the operating cam for the pot box. Can you confirm if this passes the damper or comes up against it. I wonder what it does? is it a throttle pedal limiter and has it slipped down to the bottom of the slot?

That bolt moves away from the spring/plastic damper when you accelerate. It's as close as it gets in the pic.

As for what it does, it's one of three that attach the pedal and its bracket/linkage to the Pot Box. I think. I'll know more when I get it apart.