rugrad02

I am getting back into RC after a few years. I have a Tower Hobbies Tower Power 12volt starter with the Hobbico PowerCore 12 volt Starter Power Pack. Every time I try to start my new .40 OS engine, the starter seems to not have enough juice to kick the engine over and sometimes the insert just rubs the nose cone leaving yellow rubber streaks over the nose cone. I have tested the battery with a tester and it shows that it is normal. Both battery and rubber insert are probably 7 years old. The rubber insert is well worn. Could it be the insert? Thanks. KB

siclick33

I'm guessing it is probably the battery. How did you test it?

With a weaker battery there are a couple of cheats to help turn the engine over. Take off the glow driver. Turn the engine in the wrong direction until you just feel the compression. Put the plug driver back on and start the engine. This allows the starter to produce a bit of momentum to get over the first compression stroke.

If this is still not enough then do the same again but start the starter motor away from the engine. when it is spinning then push it hard against the spinner. This helps the momentum thing again.

The only trouble with this is if you are using a power panel. Some (not all) will reduce the current going through the glow plug when the starter sucks the juice out of the battery. If this happens your engine will never start. (you could always start it by hand though!)

As I said my bet is on the battery. I would try a borrow a clubmates and see if that helps.

Good luck.

Phlip

I agree with all that siclick33 says, but the rubber insterts do wear out as well. If it's slipping and leaving marks on your spinner, I'd replace it, too.

Phil

Rodney

Almost certainly the battery. If it sat for some time and allowed to do a deep discharge, it is probably not salvageable. If, after a full charge, the voltage drops off as soon as a load is applied, it is past redemtion.

Geistware

My Feedback: (16)

Get a better battery.
You pack doesn't have enough power to torque the motor properly.

nitro bear

My Feedback: (12)

If your battery is 7 years old it's wasted. Most hobby shops carry the gel cell type replacement battery. The starter insert may have become brittle with age. I'd replace that as well.

John Murdoch

My Feedback: (11)

It may be the battery.

jettstarblue

Wal-Mart, 16.99 for a decent sized battery. (lawn tractor sized with a built in handle) Better than a little tiny gel cell.

Jetts

patternwannabee

My Feedback: (1)

The Hobbico PowerCore 12 volt Starter Power Pack that Rugrad is referring to is a small 12v 1.2 ah gel cell type battery which attaches directly to the starter. You can actually get a replacement battery although not the normal 7ah cell (too big for the power pack).

In my experience, these batteries have lasted only a season or two at best. And even so, they're not much good at engines much over 50 size. Also, when it's cold out, forget it.

Positioning the prop as far away from compression to get a momentum thing going is a good idea as siclick says, but I wouldn't start the starter away from the prop.

If you get the replacement battery, don't expect much more than a couple of seasons.

greenboot

My Feedback: (1)

Probably the battery, but check the connections too. If the wires are frayed or broken, that will be a problem. An easy way to check is to feel for warm spots. If it is getting hot, it is wasting lots of current.

Tom

siclick33

Why would you not start the starter away from the engine?

I am interested in case there is something I have missed.

greenboot

My Feedback: (1)

siclick33,
I've seen people use the "spin and ram" technique and it seems to help a little bit. But it can burn the spinner, putting unsightly rings in it. With a good battery, it isn't necessary.

Tom

patternwannabee

My Feedback: (1)

Siclick,

I've seen people do this at my field. Perhaps you don't do it quite this way.

The starter is started 3-4" inches in front of the spinner, then banged into the spinner in the hopes that the extra momentum from the starter will give enough torque to pull the engine past compression.

Seems to me engines aren't designed to withstand that type of impact. The backplate and conrod are pretty close inside your engine. Conceivably you could force one into the other and cause some scoring, metal flakes, etc. That would be bad for your engine.

It would be much better to 1) rotate the prop against compression on the other side as you had suggested, and 2)have a starter and battery that produce enough torque.

I haven't actually witnessed any damage from this, so it's just my opinion.

Oh, one other thing, when I was beginning, my engines would often not spin freely in between compression strokes. This was due to gummed up castor. This also didn't help especially in the cold weather and with a weak starter battery. Running my engines dry at the end of the day seems to help keep them free wheeling.

Jet Doctor

Hi KB

Probably both battery and insert need to be replaced.

The insert would have got hard and therefore lacks sufficient grip on the spinner.

The battery probably reads OK on the meter but cannot deliver sufficient current. Maybe you could try and use your auto battery just to confirm(no glow connected!)

Welcome back to the hobby!

DBCherry

My Feedback: (4)

Spinning up the starter and then jamming it into the spinner is definitely not good for the engine. It's bad for bushing and bearings, whichever your engine has.

I've saw a guy do that, only to have the starter slip off the spinner and he fell forward. He had his hand on the plane (a tail dragger) and crush the nose when his eight jammed it into the ground.
Dennis-

barkin_bob

I have a brand new Hobbico power core.... It's a piece of doo doo, barley enough torque to start my .46's and trying to start my .91 it just don't work. A friend of mine has a Sullivan power pac on his Hobbico stater that works great , turns over my .91 like it was hooked up to a car battery. So IMHO replace your power core with a Sullivan power pac, that's what I'm going to do soon....... anyone want to buy a used Hobbico power core CHEAP ..... Here's a link for the sullivan http://www2.towerhobbies.com/cgi-bin...?&I=LXFT85&P=0