WD ballist resistor 12 volt system
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Topic: WD ballist resistor 12 volt system
Posted By: PatrickBeth
Subject: WD ballist resistor 12 volt system
Date Posted: 29 Dec 2015 at 10:58am
| I have a WD converted to a distributed, 12 volt battery, and coil. Do I still need to run a ballist resistor. I am going to install a electronic ignition as well. I guess I need to know the thoughts on the ballist resister, only for 6 volt systems? |
Replies:
Posted By: DougS
Date Posted: 29 Dec 2015 at 11:03am
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If you're switching to electronic ignition you may as well install a high performance 12 volt coil too. No ballast resistor needed then. |
Posted By: CAL(KS)
Date Posted: 29 Dec 2015 at 11:09am
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if your going with pertronix, just get a coil with the specified ohms mfg calls for and do away with external resistor. From pertronix website. 1. The Ignitor is designed for 12-Volt negative ground systems. 2. Leaving the ignition “ON” with the engine “OFF” for an extended period could result in permanent damage to the Ignitor. 3. See Chart on back page for coil recommendations. 4. Four and six cylinder engines require a minimum of 3.0 ohms of primary resistance and eight cylinder engines require a minimum of 1.5 ohms of primary resistance. Do not remove resistors if the coil primary resistance is less than specified. 5. If your Ignition coil has the recommended primary resistance, remove or bypass all external resistors. 6. The Ignitor is compatible as a trigger for most electronic boxes. ------------- Me -C,U,UC,WC,WD45,190XT,TL-12,145T,HD6G,HD16,HD20 Dad- WD, D17D, D19D, RT100A, 7020, 7080,7580, 2-8550's, 2-S77, HD15 |
Posted By: jaybmiller
Date Posted: 29 Dec 2015 at 12:02pm
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#2 is why I don't use them.... they should be designed and built better ! heck 40 years ago I was making my own and never ever had a problem.... Jay ------------- 3 D-14s,A-C forklift, B-112 Kubota BX23S lil' TOOT( The Other Orange Tractor) Never burn your bridges, unless you can walk on water |
Posted By: JimD
Date Posted: 29 Dec 2015 at 12:14pm
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The negative ground pertronix seem to hold up a lot better. The positive grounds, will not tollerate over voltage (jump starting from charger) or leaving on. Been there done that. Even though I sell them, I threw it in the trash on my D15 II with Postive ground. They are nice, but require a little different handling, and after 2, I decided reminding my sons was not working. To answer your question, go with a coil rated for the voltage you are using. Ballast resistors are a serious pain in the bohonkus and the 1st thing I replace when one comes in my shop for a tune up. ------------- Owner of http://www.OKtractor.com" rel="nofollow - OKtractor.com PM for an instant response on parts. Open M-F 9-6 Central. We have new and used parts. 877-378-6543 |
Posted By: Steve in NJ
Date Posted: 29 Dec 2015 at 12:43pm
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The Pertronix units are great units in general. But, like anything else, you need to know what your doing. The E.I.'s are designed to use with the stock OEM coil, which means whatever electrical system your running, whether 6VPG, 12VPG, or 12VNG, you need to use the correct coil and hook-ups differ. If you go by the instructions that come in with the E.I.'s you won't have any problems as long as you can read and look at the pictures provided. You do need to remember when you want to charge up the Battery, NOT JUMP START disconnect one of the Battery terminals from the Tractor while doing so, so you don't take the chance on throwing a spike to the E.I. module and blow the module out! This can be easily done by leaving the key ON when you went to start the Tractor and found the Battery was dead or low. Anytime you're running 12VPG or 12VNG with a 4 cylinder engine, you need to have 2.7-3.3 Ohms of resistance in the Ignition circuit. Using a 3.0 Ohm coil puts you right in the ballpark and a ballast resistor (which is a PIA anyway) can be eliminated so Mother Nature doesn't play havoc with it on hot humid or rainy days causing the engine to miss and run lousy. The high performance coil that Pertronix offers is strickly optional. You don't have to purchase it with the E.I. kit as long as you use the correct coil for your application. If you want a little more fire in the hole, that's your option. Its all about being careful and watching what your doing. Most of the issues with E.I.'s are self inflicted because of forgetfulness or improper install. The units themselves are pretty damn reliable. The 6VPG one that I have in my B is going on 16 years old! We sell a ton of em' and we always have repeat customer's coming back and purchasing them for their other Tractors or when I'm rebuilding their Distributor have me install one. One of lifes nice little upgrades for the Tractor owner.... Steve@B&B ------------- 39'RC, 43'WC, 48'B, 49'G, 50'WF, 65 Big 10, 67'B-110, 75'716H, 2-620's, & a Motorhead wife |
Posted By: rob(ont)
Date Posted: 29 Dec 2015 at 4:55pm
| Steve, been having issues with a D17IV. 12 V neg ground. Ran good for 15 years, started missing this summer, by fall would not pull itself across the yard. Replaced the broken but still working ballast with a 3 ohm resistor, had 12.6 V in and out. Replaced coil (tried 2 different ones) with one labeled as "does not need external resistor". 12.6 V in and out across the primary terminals with no ballast. Full voltage at the points. Tried a combination of ballast and coil, same results. Would run well for 10-15 minutes, then back to missing badly. Tried two different point and condenser sets. Currently running but seem to be having issues with condensors based on weak, yellow spark. Any idea why I am not seeing voltage reduction at the points. Got everyone around here baffled. Any ideas?? Rob. |
Posted By: Dnoym N. S. Can.
Date Posted: 29 Dec 2015 at 5:54pm
rob (Ont) you won`t see a voltage reduction at the points when the points are open it only happen if the power is being used :: if you want to test it u can used a ballast and a light hook up to a battery and with your dvom you can read what your voltage are clear as mud right ps did you change your rotor button B:-) Dnoym |
rob(ont) wrote:Posted By: Macon Rounds
Date Posted: 29 Dec 2015 at 6:03pm
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Rob Sounds like the charging system is not keeping up with the voltage usage of the tractor. ------------- The Allis "D" Series Tractors, Gravely Walk behind Tractors, Cowboy Action Shooting !!!!!!! And Checkmate |
Posted By: Steve in NJ
Date Posted: 29 Dec 2015 at 9:28pm
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Rob, Give me a call tomorrow or at your conveinence. I'll give you some idea's and I have a few questions to ask ya to get a little more backround on your delema.. Be happy to help ya out if I can... Sorry, forgot to post the number! Steve (973) 632-5596 ------------- 39'RC, 43'WC, 48'B, 49'G, 50'WF, 65 Big 10, 67'B-110, 75'716H, 2-620's, & a Motorhead wife |
Posted By: Gerald J.
Date Posted: 30 Dec 2015 at 8:25am
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There should be only two possibilities of voltage at the points. Full battery when open, and zero when closed. With the ballast resistor in the circuit, the battery post on the coil should show battery voltage when the points are open and half battery voltage if the points are closed AND the resistance of the ballast resistor and the coil are the same. In my experience, yellow spark shows the condenser is bad and the points won't last well. Other indications of condenser having the wrong value is metal migration between the points, one developing a divot and the other a peak. Gerald J. |
Posted By: Carl(NWWI)
Date Posted: 30 Dec 2015 at 9:46am
What the difference, leave the key one with a points system and the coil will blow... All my gas tractors have 12 volt electronic ignition and the pertronix 3.0 ohm coil. Absolutely no problems and it always starts, rain or shine. |
Posted By: Brian Jasper co. Ia
Date Posted: 30 Dec 2015 at 11:42am
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I have Ignitors in both of my gas tractors. Save yourself some hassle and get the matching Flamethrower coil from Pertronix. My CA has had the same coil and Ignitor in it for over 15 years now. I have found with the Ignitor, Flamethrower coil, and .045 plug gaps I never have fouled plug issues anymore. I'm going to have to agree with Carl on leaving the key on. That's not an Ignitor problem, that's an operator problem. Both the CA and Oliver 60 have never started as easily or idled so smoothly on points as they do with E.I. ------------- "Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford |
Posted By: jaybmiller
Date Posted: 30 Dec 2015 at 11:51am
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CArl , coil should never blow as it was designd to have 4 amps of current run through it and with the proper ballast resistor it will get 4 amps, Yup, be a tad warm but IF properley designed and installed correctly it should last for decades. probalm is nothing is designed and built properly these days.heck I've got a 67 mustang coil that fires up fine after 50 years..... My real problem with 'electronic ignition' systems is they are NOT designed properly. They should not self destruct when boosting. If they do mfr left out a 25 cent component....same thing about 'wrong polarity' hookup, costs less than a buck to protect for that.... Jay ------------- 3 D-14s,A-C forklift, B-112 Kubota BX23S lil' TOOT( The Other Orange Tractor) Never burn your bridges, unless you can walk on water |
Posted By: rob(ont)
Date Posted: 30 Dec 2015 at 12:27pm
Steve, thanks for the offer. I do have a petronix ordered through a local engine shop at a pre- CAN$ crash price. We will see if it comes through. What are the preferred plug wires to use? Have been told that the ignitor likes a resistor wire better? I was prepared to order from you, but the price they gave me was the same. Add 35% plus $30-40 shipping plus (plus 35%) and maybe duty makes buying ANYTHING out of the States very hard right now.  . Sure was nice when we was on even footing. Right now this is behind the 8010 cooling issue, just got a recore radiator back, combine maintainence, a leaky seal on a New Holland vineyard tractor, steam engine rebuild and certification, etc. |
Posted By: Steve in NJ
Date Posted: 30 Dec 2015 at 10:04pm
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I understand completely. Its a shame how they beat up our Canadian comrades with all this border duty BS and what not. Everytime I send something up to Canada, I have to make the paperwork out down here and present it to the PO clerk to process before they do their thing. Its rediculous sometimes. If you still have troubles Rob, give me a call. Sure would like to help ya out if I can... Steve@B&B ------------- 39'RC, 43'WC, 48'B, 49'G, 50'WF, 65 Big 10, 67'B-110, 75'716H, 2-620's, & a Motorhead wife |
Posted By: Brian Jasper co. Ia
Date Posted: 30 Dec 2015 at 11:45pm
------------- "Any man who thinks he can be happy and prosperous by letting the government take care of him better take a closer look at the American Indian." Henry Ford |
Posted By: DaveKamp
Date Posted: 31 Dec 2015 at 1:26am
Jay, the coil is designed to carry a certain amount of current, for a certain duty cycle... or as they used to call it... 'DWELL'. When the engine is running, the points are open for a large portion of the time, and closed for a small portion. Let's say that the engine is running 1000rpm... that's two cylinders firing every rotation, so 2000 times a minute, and let's be generous and say that the points are closed for 30 degrees of each firing event... that comes out to 60 out of every 360 degrees... or only 16.6% of the time. If the coil's RESISTANCE amounts to only 4A of flow, the net power flow through the coil primary is only the equivalent of 0.66A. Since the coil is a REACTIVE element, it's frequency dependant, so as the engine speeds up, coil IMPEDANCE starts restricting current flow MORE, so the actual power equivalent will FALL. This is why coils and points burn when the key is left on, but engine not running. Now here's a not-so-big secret... coils that are built with intention of using external ballast, are made to operate at LOWER SUPPLY VOLTAGE than a 'normal' coil. A coil intended for ballast resistance is typically wound to fire substantially well at about 25% LOWER voltage... a 12v coil will fire well at around 9v... and they do this very intentionally, because when the engine is CRANKING, the battery is pushing the starter hard enough so that there may be substantially less than 12v available to fire the coil. SO... they wind the coil primary for 9v, and when cranking, it hits hard... but once you release the starter, the coil gets it's current through a ballast resistor, which limits current flow through the coil, so effectively, a 9v coil will survive at 12v. Unfortunately, it's another point of complexity and failure, but it works very well on high-compression V8's in extreme temperatures. One could say that the 'ballast resistor bypass circuit' is the '70's era equivalent concept to the 'magneto impulser' of the brass era. And the Trebuchet is the 'atomic bomb' of the 14th century... And Audi is the Polaris of motorcars... and Polaris is the Cadillac of snowmobiles... Did I digress? Perhaps the end is near... oh yeah, that's right... it's tomorrow already... HAPPY NEW YEAR, Everybody!  ------------- Ten Amendments, Ten Commandments, and one Golden Rule solve most every problem. Citrus hand-cleaner with Pumice does the rest. |