Fatuba

My Feedback: (17)

Hello Fellow RC'ers.

I have a Sullivan Dynatron that I am going to be setting it up with a A123 6s1p thats 19.8v at2300mAh.

I would like to put some kind of relay switch tobe able to switch back and forth from19.8v to 12v and then 19.8v as needed.

Anyone have any kind of ideas or schematics.

Thanks,
Fatuba

airraptor

My Feedback: (66)

why?

DMcQuinn

My Feedback: (13)

Something like this will be close. With the switch in oine position you will be running from one battery (9.9 volts). Put the switch in the other position and you will have the full 19.8 Volts.

Fatuba

My Feedback: (17)

To be able to use the same starter on smallar engines that you use on bigger engines.

Fatuba

My Feedback: (17)

The a123 is one battery 6s1p producing 19.8v

Gray Beard

My Feedback: (-1)

I'm with AR, Why?? My starter is on 18 volts and fires up everything from a 50cc to a .25. It's not a problem at all, just an easier zing on the smaller engines.

Fatuba

My Feedback: (17)

R u saying that 19.8v in small burst (no more than 10-15 sec) on a 26cc gas engine won't harm the engine?

airraptor

My Feedback: (66)

yes dont worry about the extra rpm on smaller engines. if you flooded the engine it will breaksomething on 9 volts or 19 doesnt matter.

K.I.S.S = Keep It Simple Stupid

Not calling you stupid either lol just why add complexity to something so simple.

Gray Beard

My Feedback: (-1)

I'm saying a 19.8 volt on a starter won't hurt a .049 glow engine unless the engine is flooded and is vapor locked. I just put the 18 volt battery on my starter a couple weeks ago and have used it on a couple of .46 glow engines. Mine is used on .91 to 1.20 glows a couple times a week. I used it this week on a DA 50cc and a DLE 30cc then went back and fired up my 1.20s. IF by any chance a little glow engine is vapor locked then a big battery on a starter can break the rod or crank but I have never vapor locked a gas engine. I do roll them all over by hand before I ever touch a starter on any engine though. Unless a gas engine is having a starting problem I usually just hand start them though. If for any reason you think you need to lower the voltage then by all means do it but it isn't needed at all.

Fatuba

My Feedback: (17)

I usualy start my gas engines by hand also but this 26cc is breaking in andsometimes it does not want to start by hand.

I will first flip it a couple of times like I usually do and then if it does not start hit it with the Dynatron starter at 19.8v.

Thanks for all your input guys. Makes life easier.

KW_Counter

Why does it matter why he wants to do it?
It's what he wants to do so help him out if you can.
KW_Counter

Gray Beard

My Feedback: (-1)

Read the thread from the top, he has two show and tells, if he wants to do it he knows how. There just isn't any reason to bother with it except a just because he can. A 26cc engine isn't really a small engine either.