Author [expand]	[Modern View]
berney vonk 11-12-2009 14:56:27 12.180.53.130 740884 Report to Moderator	I have a 6volt 1949 8N. I don't have spark at the spark plugs. replaced the coil and condenser. points look good. 2.7 volts is getting to the coil. Is that right? help [Reply]   [Send Email]
John (TR) 11-12-2009 17:30:13 216.24.113.74 740903 Report to Moderator	Re: electrical problem 8N in reply to berney vonk, 11-12-2009 14:56:27   Here's a picture of a new replacement point plate. The insulator under the concave head screw is plastic, not brass crimed over paper. I've personally had problems with the 60 year old paper insulator under the concave screw no longer insulating. If you carefully drill out this insulator with a small drill you'll find a square hole. Then you take the plate to Autozone and pick up a pack of plastic insulators like what the ones that come in a new replacement plate. Anymore I automatically replace the fiber insulator with plastic if I have one apart. Its cheap insurance and I don't like removing distributors from front mounts with radiator shrouds.   [Reply]   [No Email]
JMOR 11-12-2009 15:05:21 72.181.156.161 740887 Report to Moderator	Re: electrical problem 8N in reply to gahorN, 11-12-2009 14:56:27   berney vonk said: (quoted from post at 18:56:27 11/12/09) I have a 6volt 1949 8N. I don't have spark at the spark plugs. replaced the coil and condenser. points look good. 2.7 volts is getting to the coil. Is that right? help That is a reasonable number with points closed. Should go up to battery voltage when points open, if stays at 2.7v with points open, look for short circuit in distributor at usual suspect places, such as coil pig tail, condenser, condenser lead, two insulated places on breaker plate where points and condenser and pig tail make contact, etc.   [Reply]   [No Email]
Bruce (VA) 11-12-2009 15:03:48 24.125.26.10 740886 Report to Moderator	Re: electrical problem 8N in reply to berney vonk, 11-12-2009 14:56:27   Assuming that the bushings & advance weights are ok, the most common electrical failure (no spark, weak spark) points on the frontmount are: 1. The insulator under the concave head screw. 2. The insulator at the end of the points where the copper strip attaches. 3. The copper strip grounded to the plate. 4. The condenser wire grounding. 5. The pigtail/tab not making contact. 6. Incorrect positioning of the spring clip on the plate causing the pigtail to ground. 7. Incorrect seating of the coil on the distributor. 8. Water/moisture inside the cap due to gasket failure or the absence of a gasket. I'd say you are having problems 1,6 or 7. To find out, you need to pull the distributor & do a continuity check. First, dress those new points w/ a piece of card stock or brown paper bag. (I don't care what they "look like"; while you can see pits & burning, you can't see corrosion or grease) Next, you need to do a continuity check on the distributor. Make sure your meter/light works (don't ask....) Now, follow these steps: 1. Coil off, cap off, points open. One probe on the brass screw & the other on both sides of the open points. On the side closest to the cam, you should have continuity. Not on the other side! If you do, you will also have continuity everywhere because the points are grounded. 2. Coil off, cap off, points open. One probe on the brass screw & the other anywhere on the body of the distributor. You should have no continuity! Now, rotate the tang on the distributor....as the points open & close, you have continuity (closed) and lose it when they open. 3. Coil on, cap off, points open. One probe on the lead on the top of the coil, the other on the cam side of the open points. You should have continuity! 4. Coil on, cap off, points open. One probe on the lead on the top of the coil, the other anywhere on the body of the distributor. You should have no continuity! At this point, I just put the distributor, coil & cap all back on the tractor as a unit (it’s easier to do this from the left side). The reason I do this is because it is real easy to get the cap or coil mis-aligned trying to put it back together one piece at a time & the result is something gets broken or you get a ‘no spark’ problem. Post back w/ results or more questions. 50 Tips   [Reply]   [Send Email]