Ignition System Question

[thatguy]

OK - I am not a novice at rebuilding/redoing/upgrading automobiles of all shapes and sizes, but I have come across a problem that has totally stumped me as well as a few of my car repair friends.

The situation is as follows:

1966 Beetle w/1972 1600 Dual Port. Converted to 12v from 6v. Was running for well over a year after I purchased it. #4 piston rod and bearing shredded in the case. Pulled the motor, replaced the offending parts, reassembled the motor, and replaced it in the car. Now the difficulties begin...the motor will crank all day - but will not even cough like it wants to try to start. The fuel is flowing properly through the lines and into the carburetor so that is not the issue. When the key is in the "on" position, I am getting 12v into the coil as well as out of the coil into the distro cap. I get 12v in the center point of the underside of the cap, and 12v on the points. But here is the issue - I get NO spark anywhere!!!!!

I have tried getting a spark on the line coming from the coil into the distro and on the line on all 4 of the plugs with no results. I have used my coil on a separate vehicle and it starts just fine. I touched a "hot" lead to the center of the rotor cap and checked the flow of power through it and get a full 12v through it. I can hold a "hot" lead on the plug wires and get 12v through them. The ignition switch tests fine. All of the other electrical systems work( i.e. radio, lights, wipers, etc.). I have 2 manuals that I am going off of for schematics and can see nothing amiss there. Remember that this car was running at one time! I clearly labeled everything BEFORE I tore it all down.

I have done everything I can think of and am just plain stuck. I cannot see where the break is.

If anyone can help, PLEASE lemme know!!!! I don't mind calling long distance if it means I will get my Bug up and running again!

Please someone help!

[thatguy]

Forgot to mention that the timing is as spot on as I can figure out. TDC and the #1 piston is all the way up. The rotor is pointing dead at the #1 plug wire in the dizzy....

[rokemester]

I would cover all your bases and post this on Samba as well. I'm haven't gone through all of your pain but I'm struggling to getting Murray running as well. I'm hoping that I solved part of the problem by cleaning out the fuel line. The car had been sitting for 5 years and the old fuel was pee yellow and sitting in the carb bowl when I removed to rebuild. What is the best way to test for spark? John Muir says to hold the spark plug wire 1/8 inch from metal and watch for arc, but the spark plug insulator doesn't allow the metal end to get that close.

The distributor is installed correctly right? I've seen on other posts people have installed the distributors 180 degrees opposite of where it should be. I don't know if this would cause your issue though. Samba has many threads on ignition gremlins.

[thatguy]

The distro is on quite right...and if it it wasn't, I am fairly certain I should still get spark from the coil to the distro cap - but I am not! This is giving me all kinds of fits 'cause it doesn't make any sense!!!



As to your question about the spark testing...I use a known good plug in the wire and just check and see if there is spark jumping on the end of the plug. That works for me and is easier than trying to find a good ground and get the wire twisted to a point I can see, etc. That's what I do and it worked for over 20 years! Hope it helps!!

[Yuzee]

Check that the timing is not 180 degrees out and that condenser is correctly connected to the earth side of the coil.

[Blue Baron]

How old are the "new" points you're using? It's common for the tungsten surface to get an invisible coat of corrosion on them that stops spark cold. This can happen to new Bosch points that are still in the blister that have been stored for several years. Clean the surface of the points with a sharp blade.

You said you tested the power through the rotor, but I'd still replace it just to see what happens. I've had rotors go south on me before.

Do you have access to another distributor or can you borrow one? When I get stumped like this I start switching major components until I pinpoint the problem. You may also want to consider switching to a Pertronix module.

[scruffy]

have you switched your 180 degrees to see if it would fire that way? I had one that was off and it was not firing,of course i didn't pull my rocker cover off to check if both valves were closed.never did switch out the dist drive back to where it supose to be.

[JohnnyB]

check the ground wire on the inside of the distributor...Might of gotten disconnected which would adhere to your problem. Some distributors have a thin braided copper wire that is soldered to the distributor housing while others are a simple push on terminal. If this wire is unattatched, spark won't travel out of the plug wires. You will obviously still have power from the points because they get power from the coil/ign. switch and are grounded inside of the housing. Hope this helps!

[Kiwi66]

If you have electricity flowing to other points as as explained by you then it sounds like an earthing problem. Check that the dizzy earth wire is not broken and that the earth connection is clean & secure and making good contact. Also check that the chassis earth connection is clean and secure. I had the situation where the earthwire in the body of the dizzy had come just a little loose, but it was enough to stop the flow of electricity/current.

[Kiwi66]

Sorry, I was a bit quick in replying - thus this follow up. Remove your distributor. Remove the rotor, points etc then check the earth wire is secure and in tact. Look at both connection points of the wire. Install new points and condensor and rotor (the cost is very little). Set the points to the correct gap. Dizzys are very simple pieces of machinery but can cause real problems. My experience is to really understand how it works then work systematically through checking/replacing the key parts(earth, points, condensor, rotor) then you should be ok.
But if you dont want to do this remove the dizzy and take it into your local auto electrician and ask for it to be checked. Again, wont cost much. And Blue Baron's point of borrowing a dizzy and seeing if that works is a good one. My email is roso@clear.net.nz if you want to chat. Off to work now but will put a post on my Kiwi66 blog if you want me to post photos etc of what to do -over the weekend. Just let me know if you want that support. Must run. Cheers.

[fatalifeaten]

Holy 2 year old thread resurrection batman!

[Kiwi66]

Good catch. wouldnt it be great if the original author posted how he effected the repair.

[thatguy]

Sorry!

I just pulled every plug, plug wire, the points, coil, distro, ...you get the point... and started over; one piece at a time testing on a second engine in my garage until I found the culprit. Nothing was wrong w/any of the parts!!!! Everything worked on the new motor w/o fail. I then turned to the offending motor to dbbl check the actual hardware in the motor was set correctly and couldn't find an issue there.

I just began sloooowwwly to reinstall the parts and pieces one-at-a-time and still no joy.

I swapped motors with the good 1600dp and ran on down the road. I sold the bad motor to a guy w/a '71 Super Beetle and he has yet to finish.

Still bumfuzzeld about the whole thing!!!!

[Athen_TL]

Well, this might sound a bit stupid ... but it actually happened to me a couple of years ago.

I had the same situation as described above. Fuel OK, Coil giving spark (which means that the points are OK as well, since otherwise no spark would be attainable), but no spark at either plug.

I was totally stuck. The problem was in the distributor cap. There is a little contact that sits on top of the rotating part of the distributor and flows the current. Behind that thing is a little spring that keeps the contact. This little thing was stuck and even though the current went all the way to the distributor cap, there was no contact to actually distribute it.

Changed the cap and everything worked just fine.

It might be hard to spot this problem with a casual look, but it might be worth checking out.

[Blue Baron]

Also, the rotors can go bad. Always carry a spare.