Converting to lipos

[BHChieftain]

Hi,
I'm finally converting my fastech to run on Lipos. I've rewired the ESC-to-Battery connectors with 6mm bullets to fit my lipos packs. I reset the ESC, and took her out for 1 run, but the boat stopped dead after about 4 minutes-- one of the ESC-To-Motor connectors got so hot that the solder melted and the wire became disconnected (note, the temps on the motor/ESC/Battery were good).

Question-- do I chalk that up to just a poor solder job on the existing ESC-To-Motor connector and I should just re-solder the existing smaller ESC-To-Motor connectors, or should I replace the smaller connectors with some 6mm bullets I have lying around...

Seems like the 6mm bullets would be overkill since the wires are so small... I'd rather stick with the existing smaller connectors.

Let me know what you think,

Chief

[Darin Jordan]

Hi,
I'm finally converting my fastech to run on Lipos. I've rewired the ESC-to-Battery connectors with 6mm bullets to fit my lipos packs. I reset the ESC, and took her out for 1 run, but the boat stopped dead after about 4 minutes-- one of the ESC-To-Motor connectors got so hot that the solder melted and the wire became disconnected (note, the temps on the motor/ESC/Battery were good).

Question-- do I chalk that up to just a poor solder job on the existing ESC-To-Motor connector and I should just re-solder the existing smaller ESC-To-Motor connectors, or should I replace the smaller connectors with some 6mm bullets I have lying around...

Seems like the 6mm bullets would be overkill since the wires are so small... I'd rather stick with the existing smaller connectors.

Let me know what you think,

Chief

3.5mm contacts are NOT big enough to handle the power being passed through them. They can handle the current, but there is nowhere for the heat to go. Plus, the factory soldering on the SV27 and ProBoat RTRs can be questionable.

This is a common problem.

On our P-Limited boats, we replace these with 5.5mm contacts, and the problem goes away.

However, if things are getting THAT hot, you might want to review your setup. You might want to prop down a tab, or loosen up the boat a little.

[xxxrems38xxx]

pk 4mm are great!! i use 4s lipo 2x 2s 5000mah 20c and no problem of temp.

[BHChieftain]

3.5mm contacts are NOT big enough to handle the power being passed through them. They can handle the current, but there is nowhere for the heat to go. Plus, the factory soldering on the SV27 and ProBoat RTRs can be questionable.

This is a common problem.

On our P-Limited boats, we replace these with 5.5mm contacts, and the problem goes away.

However, if things are getting THAT hot, you might want to review your setup. You might want to prop down a tab, or loosen up the boat a little.

Thanks Darin. I'll throw in the 6mm,

Chief

[Unsullied_Spy]

Yeah, if you still have the stock ESC-to-Motor connectors those must go. I run CC 5.5mm bullets on everything now and they work great.

[BHChieftain]

I've convered to the 6mm, but the connectors are still getting really hot-- but the motor and esc and batteries are cool...

I checked the drive line, seems ok.

I'm running an Octura x442 and also x642 prop, both with similar heat in the connectors (but rest of the temps ok).

I wouldn't be so concerned about it, but twice the boat just stopped dead in the middle of the lake after about 3 and 1/2 minutes-- not due to LVC... after about 10min the boat comes back to life. I'm thinking I'm hitting a temp limiter in the ESC that is shutting it down.

I'm thinking at this point maybe I have a cold solder joint in the esc-to-motor connectors-- I'll resolder them and see how it goes...

Chief