Starter Current
 

I put my Sullivan Hi-Tork starter on a current meter.
No load running is around 3 amps.
When I put a load on it exceeded the 10 amp range of my meter.
Power is supplied by 12 2400 mAh NiCds.
Anyone have any idea what the current draw on these are under load.
Thanks,
KW_Counter

RE: Starter Current
 

As with anything powered, the load is variable. It depends on so many things such as the compression of the engine, if it's a four stroke or a two stroke A four stroke has one compression cycle per two revolutions where a two stroke has one compression cycle per revolution, so the load would be greater with the two stroke than a four stroke.

And of course, the load will vary with different engine displacement and manufacturers.

I hate to be so broad with the reply, but that's pretty much the best answer someone could come up without knowing more.

CGr.

RE: Starter Current
 

yea there are just way too many factors to even begin to consider what amps "you" should be pulling, no two starter setups are identical, meaning my setup will read different amps as compared to yours as compared to the next one, amps measures the flow of electrictiy through all the wiring, the connections, and circuity including that in the starter. more resistance = more amps needed. what, if any problems are you having?

RE: Starter Current
 

Are you just interested in the current figure, maybe load up the starter until it stalls and get the current value, or are you concerned about some kind of performance issue? The batteries you are using are sufficient to power the starter, you may find a limit to how much torque the starter has to turn over an engine, probably more of a limitation than electrical energy. Run time on the starter will vary according to the load, whether you can get 10 starts or 50 out of a fully charged battery pack.

RE: Starter Current
 

I understand there are to many unknown variables to calculate the load.
Has anyone put a meter on their starter while running it and measured the current draw?
Thanks,
KW_Counter

RE: Starter Current
 

Wellllll.... probably not. If it turns the engine, well, what's the point.

I have the same starter motor that turns engines ranging from .40's to 1.20's. And it turns them over and they start, so I don't care much what current they are drawing. My battery is one of those Sears emergency car booster starter thingies that I bought 10 years or more ago. It will start a car, so it is sufficient to start an engine that is a fraction of the displacement than my car engine is. I also use it to power my fuel supply pump and to charge my glow driver. So, I suspect that it is sufficient to do what I want it to do. I have an OS 1.60 that I am getting ready to install on a Seagull Super Star. I fully expect it to turn that engine over too.

I'm not trying to be sarcastic here, but what's the point, KW.

CGr.

RE: Starter Current
 

Hi-Tork Starter. The original standard Sullivan starter for many years. Features a plastic drive cone, 2.50" diameter steel body and yellow end caps. 12 VDC operation, maximum 80 amps. 210 in-oz (148 N-cm) of stall torque. 5500 no load RPM. For most engines up to 0.60 cubic inches (10 cc) and many to 1.20 cubic inches. No. S600.

From: http://www.sullivanproducts.com/StartersMainFrame.htm

I have no idea what mine runs when I am using it. The 80A figure for the Hi-Tork starter is impressive, though.

RE: Starter Current
 

I have put an ammeter on my starter. I have a Hangar 9 heavy duty(about 12 years old). With no load, the starter pulled about 5-6 amps.

When I stalled the cup with my hand, it pulled almost 30 amps. I have never tried it while starting an engine. I may do that someday.

RE: Starter Current
 

That's understandable. Given a certain load, the engine/motor will work harder or less. Grab the cup and try to hold it back, well, the motor will try to keep the same revolution so it will draw more current to try to do so.

I've seen gear reduced starters that don't turn as many RPM's but sure have a lot of torque and will turn a cement mixer over if needed... :D

CGr.

RE: Starter Current
 

Crossman,
Thanks for the info.
My NiCds are dying in my starter.
I am planning to switch to LiPos and wanted
some idea of usage to help choose some properly
sized batteries.
Have a great day,
KW_Counter

RE: Starter Current
 

I have had a Sullivan starter powered with a small lead/aid motorcycle battery for over 30 years. I always use an inline auto fuse on one wire, because my flight box is made out of sheet steel. I cannot recall the details of 30 years ago, but I imagine I started with a 10 AMP fuse and increased it as needed so it would not blow. My guess is I am using a 20 AMP fuse. I don't recall ever blowing a fuse after the initial testing.

RE: Starter Current
 

In their catalog, they have a pack designed for some sub-c batteries that attaches to the starter. The Sullivan website.

"PowerPac Battery Case. Holds 12 Sub-C NiCad batteries, providing 14.4V of high amperage power. The PowerPac will deliver as much torque as a motorcycle battery.

Fits all Sullivan Starters as well as most other brands (may require minor bracket modification). For 24V applications, two PowerPacs and be connected in series. For installation instructions on the Dynatron starter, click here.

The case features glass filled resin construction, cooling slots and bronze contacts (no soldering is required). Includes UL listed trickle charger. NiCad batteries and starter not included. Uses twelve 1200 mAH or higher Sub-C NiCad batteries. For installation instructions follow this link. No. S640."

http://www.sullivanproducts.com/Star...sMainFrame.htm

RE: Starter Current
 

That's why I measured mine, to see what kind of C rating I would need to use a lipo. For now, I am still using a gel-cell as long as it holds up.

RE: Starter Current
 

The stalled current of the starter is determined only by the total resistance of the battery, leads, brushes and windings. Because the starter isn't rotating, there's no back-EMF to reduce the current.
If you absolutely must know what the current might be, you can use a multimeter to measure the total resistance of the starter and leads. Current =12/(resistance). It will be a big number, but the actual current won't be more than that.
My starter set-up is limited by lead resistance rather than the battery performance and I start my big engines (1.20's) by hand. Once the knack is learned, I can get 'em to go, usually on the first flick.