So my daughter hit a stump tearing around in the back yard the other day, and afterward her truck was making an awful noise and putting down power intermittently. Time to put it up in the air and see what was wrong. First I needed some sort of makeshift lift for such an unusually-sized vehicle...
An old folding side table works nicely. There’s a nice lip between the “transmission tunnel” and “firewall” that I was able to wedge it into so that everything stayed put. With that, I could access the gearboxes, and immediately see what I thought was the problem.
The left-side gearbox was cracked open. Seemed like a simple enough fix if the gears themselves weren’t stripped - I would just take it apart, epoxy use some epoxy and filler and slap it back on. To get to it, though, you need to do a bit of disassembly. First, the seats come out. They are held on with 4 screws that are clearly visible from above the truck.
Next, two screws under the bed come out.
Then there are two more on the other side of the axle - these required some crawling to get to.
Finally, the there are two screws in the fenders - one in each. After I spent half an hour searching for my short screwdriver, I realized just taking the wheels off would make accessing this easier.
The “SVT” logo center caps come off just by squeezing them to open the plastic tabs.
Underneath is a simple cotter pin.
With the wheels off, the screws in the fender are easy access. After that, I had to cut the graphic stickers with a razor blade along the bed seam to free the bed. My kiddo was not amused.
Behold the power of two-motor-two-wheel drive. Now we can pull the bad gearbox... Oh wait, what’s this?
One of the tabs had actually sheared off of the motor. That explains the intermittent power. Interestingly, the way this thing is wired up the right motor still spun in “2nd” gear (high-speed), but there was nothing in reverse or 1st. Both motors run in R, 1, and 2 when they are both actually hooked up.
At this point, repair wasn’t really an option. I went to ML-Toys and resisted the urge to buy an 18V conversion kit. Since the other motor was likely close to a similar fate, I decided to pick up 2 OEM motor/gearbox combos. The owner of ML Toys doesn’t screw around. They shipped same day and were at my door 2 days later. I’ll definitely be heading back to upgrade to 18 or 24V later on when my son gets this thing in a year or two. My daughter is big enough that a 50cc quad is the next step for her.
Interestingly, these have white hubs and the originals are orange. Supposedly, this is an updated, more durable design from Fisher-Price. AS long as it works for a few months until she hits something again, I’m happy. Next step was to try to de-solder the spade connectors
Unfortunately, my crappy soldering iron didn’t have the balls to melt whatever solder the factory used to put secure it in the first place. So I just cut them off.
The smart thing to do at this point would have been to solder on new spade connectors. But I was doing this after a long day at work and not thinking straight (more on that later). So I just stripped the wires and proceeded to just attach the wires to the tabs with a small mountain of solder. Hopefully it stays on and if it breaks it will just break the solder joint, not the motor tab.
At some point while doing the other side, I dropped my soldering iron and instinctively reached out to grab it with my left hand. That didn’t end well for me. I did remember to disconnect the battery at least, so I managed to not shock myself.
The cool thing about burns like this is that they pretty much destroy the nerve endings and really don’t hurt that bad. So I just pushed through and got the other motor attached.
Reverse the disassembly steps, and it goes back together in 5 minutes.
Before I put the seats back in I gave it a test. The battery was nearly flat, but both motors ran in R, 1, and 2. Success! Time to wrap it up.
And now the battery doesn’t want to charge. Not sure if it is the battery or my rapid charger that has crapped out. I have it on the trickle charger with fingers crossed. But overall, I’ll call this a success. At some point down the line I’ll post again when we go 18V or 24V.
PS - Just after writing this, I took the dogs for a walk and my neighbor two houses down is in the process of replacing the clutch on his Ranger in the middle of the road using a floor jack, 2 jack stands, some 2x4's and a few hand tools. At night. My little success seems positively insignificant in comparison.