All, I know this is a topic that comes up here from time to time. I did a search but I didn't really see a name for a person/company to check and rebuild my distributor. Here is why I am thinking distributor rebuild (advance mechanism)... When attempting to tune my car, I observed that I am not getting full advance out of the distributor. When setting the initial timing to 5 degrees, and checking again at 5000 RPM, I don't get near the 36 degrees total advance. When I rev the engine, I see a small retard of the timing before the advance kicks in. Doesn't seem normal. We see the mark on the flywheel drop "back", before going the other direction and it never gets to full advance. When I increase the initial timing, I get popping and spitting. Seem like I may be getting 22 degrees total advance when I check it at 5000 (really gets loud at 5000 RPM!). So, my question... Who can you guys recommend to check my distributor and repair if necessary? Thanks!
The weights are sticking. For a temporary fix, remove the cap and rotor, and with your hand turn the shaft in the advance direction to physically move the weights and allow them to free up a little bit. A better way is to remove the distributor, strip it down to the advance works, then clean and lubricate. Also look for worn parts that might make the advance/retard sticky. It's actually a simple job, and done with a few hand tools. If you can set the timing, you can do this job. John
I did what you are suggesting before starting. The advance seems to move freely, but it's hard to tell in the car however. It was gone through supposedly within about the last two years. I suspect it may not be correct.
as john mentioned it is not a big job. only thing you have to be careful: when you take out the weights there are pins inside, springs and washers. you have to put it together as you dismantle it, otherwise the advance will be not correct anymore. best would be to take it after cleaning and greasing on a test bench to check the complete advance
Call me at Ferrari of Atlanta. I have the machine to test it. Not all of the old Sun distributor machines can do electronic or magnetic pick-up, mine is modified to do that. I can fix it and retest it to verify it's function.
I'd likely rather have a professional look at it, as I have no way to bench test the advance, which I think is the problem... Wade: I'll give you a call. Thanks.
Norwoods also has a machine and did a great job rebuilding mine. money well spent since the sticky weights made the car run oddly
9 out of 10 times, actual issue is from carburetors and most unexperienced mechanics start changing ignition parts, so check you carburetors before ignition. But if issue is with ignition, sticky counterweights is most cause feom this type of distributor; here is pictures from my project and there you see what you have coming AND DO NOT MESS AROUND WITH THOSE COUNTEWEIGHT WASHERS AND SPRINGS! http://www.ferrarichat.com/forum/boxers-tr-m/451351-my-512bb-diy-thread.html
The carbs likely need some tuning on my car, but it wouldn't cause the timing not to advance of course, so I wanted to start there. Once its right, I was going to move to the carbs. Which will likely lead to more questions! Thanks.
