I just bought an OS 75ax engine...1st I had a regular hobbico 90starter which wouldnt turn it, now I bought the heavy duty hobbico 180.....still doesnt turn it over, just sits on the hub and spins, the harder you press against it, it spins slower. Does anyone have any recommendations on a starter that should work? Btw I have two starters for sale!! Thanks

Get more voltage or at least higher cranking amps going to your starter. When it comes to dc motors voltage is power.

I have an 18v drill battery from harbor freight, on a cheap starter. http://www.harborfreight.com/18-volt-battery-67029.html I have yet to find a model engine it will not turn.

Another faster available answer may be a lawn n garden battery.

I have the same engine. What I do is rotate the prop in the opposite direction of normal rotation until it reaches the beginning of the compression stroke. Then, I start the starter, but not against the spinner so that it has some momentum, then quickly press it against the spinner. That usually gets the job done.

BUT... before you do this, remove the glow plug, turn the plane over so that the glow plug socket (without a glow plug) is pointed down and then rotate the prop to get out any excess fuel. You don't want to hydro-shock the engine.

If you flooded the engine, fuel will come out of that glow socket. When it turns without fuel, turn it back over and rotate the prop several times more. You can use the starter for both of these evolutions.

Put the plug back in the engine, then go to step one above and try it. Don't forget to tighten the glow plug and connect the glow driver.. [X(]

CGr.

One more thing.. clean the rubber grommet.. whatever it is called, that goes against the spinner, as well as the spinner. If there is any oil on it, well, you get the idea.

CGr.

Voltage. If your using one of the flight box batteries then voltage for sure. They loose it fast and require quite a bit of charging. I'm using a 12 volt car jump starter and it rolls over my 1.40 gas engine but when I get around to it I will be using one of the 18 volt drill pack batteries.

marshrabbitt there is likely nothing wrong with either of your starters but first You need to answer some questions. What are you powering those starters with? What voltage? what capacity?
Is this one of the commercial portable packs? If so agine what voltage and capacity? Are you using a very long cable through a power panel?

It difficult to help without these answers.

John

Using the hub of the starter, turn the prop clockwise till you hit the back side of the compression. That will give the starter a full revolution to get up to speed.

I use a car battery with a nice handle on it. LOTS of power! [8D]

As others have said, rotate the prop backward against the compression before applying the starter.

I use a jump starter for car batteries. It works great and you can keep it in the trunk in case you ever need to jump a car battery

http://www.sears.com/shc/s/p_10153_1...=1303556541603

I think that voltage must be the problem, listening to you guys.....I do have one of those flight boxes with the power panel and the little 12 volt battery in it. Maybe I should try it off my truck battery today, hopefully that will do the trick!! If not its off the harbor freight. Thanks for all your input, appreciate it.

I use my dynatron starter with a 6 cell lipo attached to the bottom. You can take lug nuts off your truck with it. I like it for the portability, sometimes I have to go out in the runway because my plane tipped over and I can start it out there.

Phoenixangel
good morning. 2 questions regarding harbor freight battery. 1) how are you charging it? 2) What kind of connectors are you using to go from the battery to the starter. and 3) I know I said I had 2 questions. can you post a picture of your starter with the battery installed. Thanks

Used mine twice now for jump starting cars out at the field.

I use the wall wart for an overnight charge. http://www.harborfreight.com/charger...ols-67031.html I carry an extra battery in case I need it at the field,but I have not had to use it yet.

If I need a quick charge I just use a triton2 charger. The pack is actually just sub-c ni-cd cells. The rated capacity is 1.3 amps. The triton does a good job of peak charging them.

The battery has blade connectors. I just crimped some slide connectors on the starter wire. It allows me to just plug/unplug.

*edit* the battery in the pic is one from wal-mart, I grabbed the wrong one for the pic, all the same info applies however..... oops

In the interest of giving credit where credit is due, I got the idea here. http://www.rcuniverse.com/forum/m_10...m.htm#10155651 the rig shown from John is more elaborate then mine.

Still it was his post/idea, or at least that is where I got it. Thanks John

marshrabbitt,

InitiallyI had the same problem you are having. It is not a starter problem but a user problem. Though these starters are high torque, they will not be able to turn over a primed or over primed engine from the point of compression.

1) Take the glow plug off as CGR said and turn over the engine with the starter. This will expell all excess fuel. Then install the glow plug carefully again being careful not to cross thread

2) Clean the rubber insert of the starter and the spinner

3) With the booster connected, turn the prop backward by hand (or tip of the starter motor) till it hits compression. Then apply the starter. This way some amount of momentum is builtup before the engine hits compression. This will surely start the engine.

If this doesnt turn over your starter battery is low. If it turns over but the engine doesnt start there is a tuning problem

Even your 90 starter will turn over the engine if you know what you are doing. The 120 size HD starter can turn over even a 20cc gas engine
Ameyam

Thanks for the advice ameyam, I dont think there is any fuel in it yet...haven't spun over enough to draw any in there yet...took the plug out to make sure, no fuel, also took my bigger starter and cut the banana plugs off them....installed some alligator clips to use the truck battery. Gonna try the turning it backwards into the compression stroke and trying that. When I was breaking in the motor on the bench it started fine...seems I had to keep bumping it over to get it to go. This is the biggest engine I have owned, these little boogers have alot of compression! Hopefully what I have done will work.... waiting on some stuff to dry and will try it soon.

Hot Dog it worked like a charm...turned the prop backwards into the compression stroke and hit the starter and spun it over like a charm!!! Ok...no starters for sale now, Lol!!

Yeah I run at least 14v through my starter and even more helps.

Do as already stated and crank the engine back to the stop point.

I do not do what C.G.retired mentioned ( bumping the starter against the spinner ) except on much larger engines ( 50cc up ).

However you may want to consider switching to the large starter cone available for your starter ( Tower Carries some ).

This larger cone permits the starter to impart more leverage, making it much easier to turn the engines over.

With the higher voltage and the larger cone I use that same Hobbico to turn over 50cc'ers and my 1.80 four strokers with ease.

It laughs at .75's... it does..

When you rotate the prop backwards to the compression, If you leave the glow driver on, use the spinner not the blade. If your engine happens to have some fuel in it, there is a chance it will fire the fuel.

If that happens and your hand is in the way, it can hurt. Just thought I would mention it.

Pheonixangel...thanks for the tip...a little late for that, already learned that lesson earlier today, the hard way!! Still have all fingers left ..lol!

marshrabbit,

One more tip. Pick up a silicon insert to replace the one that comes with the Hobbico starters. It's crap. The rubber is harder than the silicon ones and tends to get smooth at the contact area. Thats why some people have suggested roughing up the original one. The silicon inserts really grab the spinners.

I had the same issue and bought a motorcycle battery. it works great.

Joe

Well I purchased the Harbor Freight 18v battery and have it hooked up to my spare dynatron. It certainly spins it faster than the 12v battery. I have a miller 3" starter cone on this one with a gear drive.

Gene, how did you attach it to the starter?? A photo would do. I really have to get my butt over to HF soon. Maybe Monday, I have a DR. appointment in the area of a HF store. Also in the area of three hobby shops so I guess I can count this as a road trip day.

I am more old school(or hardheaded). I have had good luck using a chicken stick. I cut off an umbrella and put a piece of air hose over the shaft to make it. My GMS 75 starts with a couple of flips. Electric starters are more of a convenience than a requirement. They work well with an enclosed motor though. The jump starters are the ticket if you get one with a lot of amp-hour capacity. Have their own handle, etc.