Tag motor slow cranking

Beamed03

Member
Looking for a little guidance on an issue I’m currently having with my Leopard tag motor. Since day one of installing my used leopard motor and wiring harness I’ve had a “slow cranking issue. On occasion it’ll crank just fast enough to start. Extremely frustrating!! New battery, new (eclipse) starter, no binding issue with the motor, flywheel teeth looks good, motor compression is 170psi, even bypassed the harness and went straight from a fully charged battery to the starter and still not fast enough!! Leads me to believe it’s a bad starter but I’m hoping I’m overlooking something as I just paid an arm and a leg for the new starter I have. And insight is greatly appreciated! Also, I have multiple grounds on clean bare metal surfaces.. thank you in advance!
 
I'd have to guess starter, since you eliminated the harness variable. That, or battery doesn't have enough CCA.
 
I'd have to guess starter, since you eliminated the harness variable. That, or battery doesn't have enough CCA.

thanks for the input Ted, I even tried the larger cca battery from my external starter and same result. Maybe this starter wasn’t happy from day one. I was only ruling it out because it was new, but then again I know all mechanical parts can have an issue even when new.
 
You changed starters and its the same as the old one ?
Connect a volt meter to the battery , hit the starter see what the volts drop down too . Better yet an amp gauge (external) starter draw gauge .
The teeth are not bottoming out on the ring gear ?
Ignition timing too far advanced ?
 
I know you said you had it running you might try pulling the plug out and try turning it over might have a internal issue. I know on our k30 at 190 to 200 psi it will make the external starter gurnt and mone Chuck.
 
You changed starters and its the same as the old one ?
Connect a volt meter to the battery , hit the starter see what the volts drop down too . Better yet an amp gauge (external) starter draw gauge .
The teeth are not bottoming out on the ring gear ?
Ignition timing too far advanced ?

the original starter would get hot and barely turn the motor over, took it apart and the brushes were gone. Just installed a new starter and fixed the old one as a backup. So yes, the old starter and new starter have the same poor results. Sometimes it’s easy to overlook the obvious when you give it to much focus haha. I’ll throw a voltmeter on and see what the voltage drops to when cranking. Is it safe to rule out a timing issue being that it cranks slow even with the ignition unhooked? Also to note, I can literally stop the motor from turning over by blocking the spark plug hole with my finger. I hadn’t thought about the teeth bottoming out, I’ll check the voltage and gear mesh hopefully tonight! Thank you:)
 
I know you said you had it running you might try pulling the plug out and try turning it over might have a internal issue. I know on our k30 at 190 to 200 psi it will make the external starter gurnt and mone Chuck.

hey chuck, I’ve actually logged a few hundred laps with the motor as is. I’m fairly confident the internal side of things are good, but it’s not to rule out. The 170 psi compression numbers are with the motor barely turning over. I’d assuming it would climb a solid 10-20psi more With some cranking speed. I don’t have the adapter to turn the motor over with my external starter or else I’d check the compression that way.
 
Bushings or needle bearings in starter ?
Dry bushings cause a big drag on starters .
Starter might need to go starter shop , or returned .
Old school mechanic with a growler to check armature .
Friction in engine or possible bent rod , unlikely if it runs out well .
The finger in plug hole points to something in the start circut .
 
Looking for a little guidance on an issue I’m currently having with my Leopard tag motor. Since day one of installing my used leopard motor and wiring harness I’ve had a “slow cranking issue. On occasion it’ll crank just fast enough to start. Extremely frustrating!! New battery, new (eclipse) starter, no binding issue with the motor, flywheel teeth looks good, motor compression is 170psi, even bypassed the harness and went straight from a fully charged battery to the starter and still not fast enough!! Leads me to believe it’s a bad starter but I’m hoping I’m overlooking something as I just paid an arm and a leg for the new starter I have. And insight is greatly appreciated! Also, I have multiple grounds on clean bare metal surfaces.. thank you in advance!
I build engines here in the Northeast, and have seen this on Leopards and x30s a lot of times. Your harness ground Wire should be hooked to the bolt on the front side ( bendix side) of the starter. We have had good luck with Mitsuba starters, the Eclipse have been hit or miss as far as quality goes. If you bypass the harness and go directly to the starter and it doesn't spin fast I would say you have a bad starter. Maybe reinstall your original rebuilt starter and see if that makes a difference.
 
Thank you all for the insight, it’s nice to get some other perspectives on things. Just to touch basis with some of my conclusions... I checked out the kart tonight, newer starter looks good inside (bearing style), reinstalled it and checked the mesh with flywheel. All is well there.. pulled the spark plug out and the motor turns over by hand very smooth, definitely no binding issues there. Also, double checked the bendix before reassembly and it is free and smooth. Ground wire from harness is attached to the starter mounting bolt (bendix side) as recommended. The motor barely turns over fast enough to engage the bendix so it was tricky to get an accurate voltage reading while cranking as it only engages for a brief time until the compression of the engine causes it to disengage.. battery was at 12.6v, while cranking the motor over with a plug in it I saw it drop to 10.5v.. in the automotive world that’s an acceptable voltage under load. Don’t have an amperage tester here so that’s as far as I got. My conclusion is still these two starters I have are weak and or unhappy. May look into a Mitsuba and cross my fingers that’ll resolve the issue. Thanks again everyone!!
 
Thank you all for the insight, it’s nice to get some other perspectives on things. Just to touch basis with some of my conclusions... I checked out the kart tonight, newer starter looks good inside (bearing style), reinstalled it and checked the mesh with flywheel. All is well there.. pulled the spark plug out and the motor turns over by hand very smooth, definitely no binding issues there. Also, double checked the bendix before reassembly and it is free and smooth. Ground wire from harness is attached to the starter mounting bolt (bendix side) as recommended. The motor barely turns over fast enough to engage the bendix so it was tricky to get an accurate voltage reading while cranking as it only engages for a brief time until the compression of the engine causes it to disengage.. battery was at 12.6v, while cranking the motor over with a plug in it I saw it drop to 10.5v.. in the automotive world that’s an acceptable voltage under load. Don’t have an amperage tester here so that’s as far as I got. My conclusion is still these two starters I have are weak and or unhappy. May look into a Mitsuba and cross my fingers that’ll resolve the issue. Thanks again everyone!!
Your voltage is too low, we charge our batteries to a minimum of 13.6, if they drop below 12.8 or do when cranking they turn slow and will not start. I bought 12v 1 amp power supply's off EBay with alligator clips , I use those to charge with instead of a standard charger.
 
Your voltage is too low, we charge our batteries to a minimum of 13.6, if they drop below 12.8 or do when cranking they turn slow and will not start. I bought 12v 1 amp power supply's off EBay with alligator clips , I use those to charge with instead of a standard charger.

interesting, i only know of automotive systems in which a fully charged battery is 12.6v. I’ll have to do some looking into this one! Thanks Dan
 
I was on the same page 10 volts is low.
Just for grins i just tested my lawn tractor 12.6 free volts 11 cranking .
Big old single techumseh .
Screenshot_20191204-123441_Chrome.jpg
 
interesting, i only know of automotive systems in which a fully charged battery is 12.6v. I’ll have to do some looking into this one! Thanks Dan
Our engines start best when the battery at rest is at 14.1 volts, and under a starter load at 13 volts or so. I know it sounds high, but the wiring harness on a leopard is poorly designed, and the line loss thru that small wiring is huge. Your lucky your kart even turned over, the ECM module ( the A box) on a leopard will often not engage the starter relay if the voltage drops below 12v. I have several stators here that will not fire the ignition when cranked by the onboard starter, it will not spin fast enough to send the signal to fire. If we use an external starter with the same stator it fires instantly. It is a poorly designed system. The new x30s in use in Europe have everything built into the coil and stator, and similar to a ROK setup all they have are 2 pushbuttons. I starts the engine, the other grounds the ignition and shuts it off. Much simpler and from the drivers I have spoke too, it works almost flawlessly.
 
Our engines start best when the battery at rest is at 14.1 volts, and under a starter load at 13 volts or so. I know it sounds high, but the wiring harness on a leopard is poorly designed, and the line loss thru that small wiring is huge. Your lucky your kart even turned over, the ECM module ( the A box) on a leopard will often not engage the starter relay if the voltage drops below 12v. I have several stators here that will not fire the ignition when cranked by the onboard starter, it will not spin fast enough to send the signal to fire. If we use an external starter with the same stator it fires instantly. It is a poorly designed system. The new x30s in use in Europe have everything built into the coil and stator, and similar to a ROK setup all they have are 2 pushbuttons. I starts the engine, the other grounds the ignition and shuts it off. Much simpler and from the drivers I have spoke too, it works almost flawlessly.
One reason why I start my wankel from the side instead of using the on board starter. Still love the old direct drive karts. Yes, more work, but when you were young and less mechanically smart I guess we could all start them and used to prefer simplicity even at the cost of working harder to start them. Besides less weight, no batteries to charge, etc. FIA/CIK caused the mess with all this TAG junk.
 
Our engines start best when the battery at rest is at 14.1 volts, and under a starter load at 13 volts or so. I know it sounds high, but the wiring harness on a leopard is poorly designed, and the line loss thru that small wiring is huge. Your lucky your kart even turned over, the ECM module ( the A box) on a leopard will often not engage the starter relay if the voltage drops below 12v. I have several stators here that will not fire the ignition when cranked by the onboard starter, it will not spin fast enough to send the signal to fire. If we use an external starter with the same stator it fires instantly. It is a poorly designed system. The new x30s in use in Europe have everything built into the coil and stator, and similar to a ROK setup all they have are 2 pushbuttons. I starts the engine, the other grounds the ignition and shuts it off. Much simpler and from the drivers I have spoke too, it works almost flawlessly.

I was able to do a little more testing over the weekend, I ran some leads off of one of my dirtbike batteries that at rest was 13.1 V. The kart cranked just as slow as usual, went ahead and started the motorcycle and The voltage went up to around 13.6v. Kart turned over like it should:). As you presumed it’s more of a voltage issue then an issue with the starter or wiring. Thank you again for leading me in this direction.
 
Not a p
I was able to do a little more testing over the weekend, I ran some leads off of one of my dirtbike batteries that at rest was 13.1 V. The kart cranked just as slow as usual, went ahead and started the motorcycle and The voltage went up to around 13.6v. Kart turned over like it should:). As you presumed it’s more of a voltage issue then an issue with the starter or wiring. Thank you again for leading me in this direction.
No problem . Go to EBay and search 12v power supply and get one with alligator clips for leads. 500ma up to 1 amp. That is what I use, works perfect.
 
I was able to do a little more testing over the weekend, I ran some leads off of one of my dirtbike batteries that at rest was 13.1 V. The kart cranked just as slow as usual, went ahead and started the motorcycle and The voltage went up to around 13.6v. Kart turned over like it should:). As you presumed it’s more of a voltage issue then an issue with the starter or wiring. Thank you again for leading me in this direction.
 
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