cammellostanco

Hey thank you everyone for the input, I did not set the topic to "follow", so I missed your msgs the first time. I will read through and let you know!! Would this give me the ability of decide the amount of power output?

Hi, I was using lithium before, the NiZn are stronger. Also, my Energizer lithium report 1.5v, while NiZn 1.6v

Hi all! So I decided to give to my 9398 crawler a new life, connecting to the v2 PF IR receiver a 3S lipo. I have used this approach. The battery I used is this, I soldered a balance plug to a PF extension cable so I could keep the IR receiver untouched. Now, the power is amazing, but I have now way of deciding it's speed. The motors are either ON or OFF. Is there a way, with my current setup, to regulate the speed? Let me give you an example: On my other crawler, the 42099 (Lego Powered UP) , when I use the Lego Control+ app, I can decide the speed of the truck depending on how much I push the trigger on the app, but it seems I cannot achieve the same on the old PF motors. Ideas are welcome!

While I wait for the new IR receiver, I went ahead and connected the old IR v2 receiver to a 3S LiPo: the thing is a monster I know I did not find the solution, but with the abundance of power, the truck is now as fast as the 42099 crawler on NiZn AA and increased reduction gearing. I have put back in the 9398 the modified gears in the hubs, that is I have used again the increased reduction gears of my previous post. Let's see what happens with a new controller

Just installed NiZn batteries on 42099, WOW, what a difference compared to NiMh. Let's see if the hold many recharge cycles and also let's hope I do not overstress the motors.

I have a V2, I purchased a new one on Aliexpress, we'll see.

Thank you for helping out. I have plugged both motors directly into the hub (brand new Energizer Lithium). Front Motor: very strong, no problem. If I hold the wheels very tight, there is no whining noise from the motor. Rear: seem to be ok as well, If I hold the wheels very tight, there is no whining noise from the motor. When I connect both motors, and I hold the FRONT wheels all 4 stop, with no whining. All 4 wheels start to spin again as soon as I let go. If I hold the REAR wheels, all 4 stop and do not re-start when I let go. Very weird: after taking apart the wheels hubs and the front/rear axles and lubricating them, the 9398, though still weak, improved a lot.... Who knows??!!! I do not think point 3 is indicative of anything though. I am waiting for a new battery pack and a 3S LiPo to see if the results are different. When I will have the $ I will try with Buwizz. On the same track the 42099 running on 1.2v NiCd greatly outperforms the 9398 on new Energizer Lithium , I point the issue to the battery pack. Will post updates as soon as I can do more testing.

OK, I replaced the gears as per the original manual. I am using brand new energizer lithium. I had to disconnect the front motor since I lost the original hub gears. It helped towards a solution, but it's not there yet The only change is that the truck now goes back and forth faster 4 or 5 times, before stopping as before.

This is a video of the noise that engines make. If I lift the truck the wheels spin again, as soon as I put it down, the whining starts again and the motors does not spin. The truck has the original open diffs, the only thing I changes is the reduction gears in the hubs. Here the pictures where I swapped the gears to get more torque, did I overdo it?

Thanks, I checked, the rims are fine, they are not slipping on the tire. I am going to make a video so the issue is clearer.

After just a few years....I revived my passion for Lego Technic. And yes... the problem with the poor output is still there. Let me recap: I removed both motors, checked the axles, etc. There is no excess friction and the motor look fin externally Both motors still have their original specs speed (400/420 rpm) measured with the yellow Lego speedometer tool I could not recover anymore the instructions to connect a 9V battery to the motor directly, any ideas?

Hello again guys, I did some testing, it appears that the issue is still there, I will be now going to test the other options you mentioned. Will update asap

hi guys, back again. I admit I was lazy and did not work at the lego for quite some time. Decided to revive it and troubleshoot the problem. I got a new battery charger and a battery tester, the 6 batteries work fine, BUT the 4x4 is still slugghish with almost no torque. More testing tomorrow

Ok, i still have the warranty. But before changing the 2 motors (looong wait) what can I try? I will try the motors connected directly to the battery box anyway. The 2 motors are hardy used (10 times or less)

Hi everybody! It seems that I just cannot get enough power out of the 2 std motors anymore. I tried with both alkaline batt as well as TOP enelopp rechargable, but no way, the crawler is not capable of pulling itself on the same slopes it used to when I tested it in the winter :( What can I try? Any ideas?