Just a word of warning if purchasing from AMS do your homework first especially with hard to get parts. I have just waited 3 months for a couple of pinion gears which they said were in stock with a 3 day dispatch. After 5 updates for extended deliveries I rang their supplier and was informed parts NLA and that they had no orders for those parts. I have now after showing them that the parts are NLA they changed their listing to discontinued, and I have received a refund but wasted 3 months. mich
AMS deserve a bad review for messing you around Mitch.
Originally Posted by vint_mow
Max, I will give your suggestion a try if ever I come across an external coil. .
Originally Posted by NormK
Max, are you saying that if I use a PT coil, from running on the outside of the flywheel I should turn it over to run it on the inside of the F/C flywheel?
Yes Norm ,you must flip the coil over so it goes onto the core the opposite way.
The reason for this is, Magnetic field lines are continuous, forming closed loops without beginning or end. They go from the north pole to the south pole.
The early Victa motors ( with the coil inside the flywheel ) the flywheel leads with the North Pole magnet but the Powertorque and Full crank side pull both lead with the South Pole magnet so the Magnetic field lines are reversed if you swap one coil from one motor to the other without installing the coil backwards.
Below I have drawn a Full crank side pull coil even though it looks like a powertorque under the drawings.
The next drawing is comparing the Powertorque to the early Victa.
I have one Victa 18 that has a big hole (in the alloy coil plate) where the coil goes so you can install a bigger coil, so yes you can adapt a bigger coil to work.
It is all a moot point now Max because the PT coil is too thick and the edges are square compared to the domed early coils. This puts the whole idea in the bin
I would have to say that in my experience AMS are not the most "customer friendly". I purchased a part from them and wondered why it had not arrived. I later logged back in and found out my order had been cancelled soon after I had placed it. It took them 3 weeks to get around to sending me an email to say the order had been cancelled. Yet to this day they still have the same part listed as "available" on their website.
Max, I was having trouble understanding the whole polarity thing, but your photos really help to explain the difference between those external and internal coils. Thanks for posting the information. I recently added some extra rare earth magnets in behind an old Pope flywheel which boosted it back to normal. Took me a while to work out the whole N/S thing, and to get the magnets so they were all facing the right direction and not repelling. I must have it right as I used a compass and the needle rotates N to S as I pass it across the face of the magnets, just as I would expect.
It is all a moot point now Max because the PT coil is too thick and the edges are square compared to the domed early coils. This puts the whole idea in the bin
Thanks for testing these coils and for the information, Norm. I have contacted numerous auto electricians and coil companies about the possibility of rewiring old Victa coils and only one was interested. One company says on their website that they can rewire coils and make custom coils, but after contacting them I got this in reply: "Sorry, we do not have this coil." Well of course not. Their answer had nothing to do with the question I asked. There are lots of big glossy websites out there making huge statements, but you contact them and they can't actually do any of the things that they claim they can do. I find this all the time. Our nearest city once had a company that had a great reputation for their ability to quickly and cheaply rewire coils of any kind. I contacted that same company recently and the person on the phone asked what I meant by "rewire a coil?". It was very clear he had never heard of such a thing. I guess this is just a sign of our throwaway mentality, which may in fact be rapidly coming to an end as a result of scarcity of resources and unstable supplies of stock parts. People may once again resort to repairing things rather than simply throwing them to the bin and buying a new one. I live in hope.
Yes Norm ,you must flip the coil over so it goes onto the core the opposite way.
The reason for this is, Magnetic field lines are continuous, forming closed loops without beginning or end. They go from the north pole to the south pole.
Cheers Max.
Max, It has suddenly dawned on me that the aftermarket coil I purchased is just as you describe. I think that is why it is labelled as suiting both external and internal setups, that being MA05183 and MA05529. The problem was this information about flipping the coil for the different setups has not been relayed to the companies that are selling the coils. I emailed one seller and it was obvious to me that he was not certain but said he thought it should in theory work. I even emailed the company responsible for introducing these Taiwanese coils to the Australian market and they failed to reply with any information. It is obvious to me now, based on what you have told us, that I will have to flip the coil the opposite way on the core to get it to work on my older internal setup. I will test this today and let everyone know if successful. I have a feeling that this is what the problem is. Kicking myself for not thinking of this sooner!
vint-mow, I even ground the edges off the coil to see if I could get enough clearance (not sure if it damaged the coil but that doesn't matter as I have buckets of them) Problem is the PT coil is about 28mm thick and the F/C one is about 21mm so I am looking at a 7mm problem. Not sure what would happen if I ground the leg to allow the coil to sit back further
vint-mow, I even ground the edges off the coil to see if I could get enough clearance (not sure if it damaged the coil but that doesn't matter as I have buckets of them) Problem is the PT coil is about 28mm thick and the F/C one is about 21mm so I am looking at a 7mm problem. Not sure what would happen if I ground the leg to allow the coil to sit back further
Sounds like more trouble than it is worth Norm. I am about to try Max's suggestion of reversing the aftermarket coil on the core. I am now convinced that this is the problem. They have made these coils to suit both internal and external flywheel setups, so for older coils you have to flip them.
A word of warning on these new aftermarket coils. The wiring is VERY fine compared to the originals and they have no large blobs of solder anymore to support the wires. I completely severed the connection between the coil and the spark plug lead screw on my coil by applying too much pressure when screwing in the lead wire. I've never seen or heard of this happening on the old coils. I had to grind down the plastic on top of the screw and rejoin it to the wire with a blob of solder. So you obviously have to be very careful not to screw the lead wire in too tight on these new aftermarket coils. Also the positive and earth wires coming from the coil are very fine and not soldered, so if you bend them back and forth a few times they will break off level with the coil. The very first thing I do on receiving these new coils is get the hot glue gun and add some big supporting blobs of hot glue around the connection points on the coil. It is not hot enough to damage the wiring. This will stop the wires from breaking off and totally ruining your day. I would think that just the vibration of the mower over time will cause many of these new coils to fail. But that seems to be the modern trend with mass production.
Well reversing the coil did the trick. The only problem is the lead wire is poking out the top and on the opposite side, so you will need an extra long spark plug lead and find a way to prevent it getting caught up on the shaft and flywheel.
I have converted a Victa points mower to pointless ignition (coil from a side pull full crank) Today just to show how easily it can be done.
This hasn't been explained before doing the conversion this way ,but is simple enough.
Originally Posted by vint_mow
Well reversing the coil did the trick. The only problem is the lead wire is poking out the top and on the opposite side, so you will need an extra long spark plug lead and find a way to prevent it getting caught up on the shaft and flywheel.
Vm ,that is why the lead wire for the spark plug goes to the bottom of the coil if possible with your coil.
Just out of interest vint_mower is the Stens Module wired for negative or positive earth ?, now it's working.
The edges of the coil needs some filing so the flywheel doesn't rub after reversing the coil.
I have installed a Powertorque module instead of the full crank module.
As far as I know if you don't reverse the coil and use a Victa module the motor has to spin a lot faster than normal to get a spark.
Also leaving the points in and connecting up a Victa module with the coil not turned around (standard points coil) will work but uses the old points as a switching mechanism.
From what Norm has said about the size of the Powertorque Coil ,I haven't bothered trying that coil.
Video below showing start up with pointless ignition.
Thanks Max, great to see a successful test. That is what I did with the aftermarket coil. Turned it backwards. Seems really odd placing it this way and looks entirely wrong, but the results speak for themselves. I just left the STENS on Negative Earth. How about you, did you wire it to neg or pos? When I spoke to an auto-electrician a while back he said it won't matter which way I wire it.
Just a question, have you actually turned the coil right around, or just on its side, or doesn't it matter? It's just that I notice the brass keeper is not matching with the slot on the coil in your photo.
I've been collecting side pull mowers for years as I wanted to convert all my older mowers to pointless ignition Norm but possibly reversing a points coil may work with a Powertorque module ,when a tried a Powertorque module on a standard points coil I had to spin the motor a lot quicker to get a spark.
From what I've read Vm on the Stens Module ,the coil will only work one way but not the other ,so if you don't have a spark with negative earth you change to positive earth on the module to get a spark.
I was thinking the Stens module would work with a negative earth with this coil setup ,must be the same way the Victa modules work .
The Victa module just has one wire connection so I have installed it as standard with negative earth.
The coil can't be turned on it's side as the coil hole is rectangular and not square ,what is difficult to see in my previous images is a side keeper that locks the coil tight on the core ,one image below shows the tab of the keeper at the back of the coil and as it goes side ways I didn't want the tab on the flywheel side.
I didn't take a lot of notice when flipping the coil over on the core but the brass keeper worked with the plug wire up or down.
Thanks Max, That explains it well. Looks like your Victa has the orientation horizontal on the core compared to mine which is vertical. Also, in my case, the arm on the core is forming an almost perfect square in the centre of the coil, not rectangular. That is what was throwing me off.
Incidentally, I've just been told that BSA Bantam coils will work on early Victa and are interchangeable as both used Wipac ignition systems, but I guess the only way to prove this would be to test one. They are Made in India and very expensive imports from UK and US, but I might be able to obtain one for a reasonable price direct from India.
I was thinking the Tecumseh pointless coil may work on the Victa laminated steel core ,the only problem is the steel core would have to be filed down slightly to fit the Tecumseh coil.
With the Tecumseh coil it would not need to be installed backwards.
Hi Max, How thick is that coil it looks fairly wide and not having a curved face makes it stick out further. I have a few Tecumesh motors here so I could pull the coil off one and give it a try
Hi Norm/Max, I was wondering about Tecumseh coils too.
Max, this is probably the dumb question of the day, but instead of reversing the coil, why not simply reverse the wiring? So use the earth wire for the positive and the positive wire for the earth? The reason I ask is that if I test an external Victa flywheel coil with the multimeter, I get the same reading in KOhms through the earth wire as the positive wire. Wouldn't reversing the wiring be the same as reversing the coil and using the same wiring?
