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A little ignition help needed

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Hi Doug, The "normal" Lucas ballast ignition and what is showing in the 1980 diagram both accomplish the same thing. Just wired differently.
Since we don't have all the necessary info on what rcufley has had done to his ignition. It's hard to fix it. Maybe when he returns we can help him.
 
I really appreciate all your input for my problem.
I am starting to think that the problem just might be a wiring issue (a little shorting out someplace). I have moved the timing mark to about 10 degrees BTDC and both the intake and exhaust valves for No. 1 cyl. appear to be closed with the rotor pointing to No. 1 plug wire on the dist. cap. So I assume the timing is close enough to correct where I do not have to worry about the timing chain and gears. Fuel appears to be flowing into the carb through the jets and the spark is strong at the coil all the way through the plugs, but looks intermitant at the points (not a steady consistant spark when cranking). When turning the ignition key to start the engine, everything works correctly up to and including the starter. A cylinder will fire off occasionally, enough to disengage the starter but the little engine will not start.
Thanks again for all your help and a Happy New Year to all!!
 
Put a jumper from the positive terminal of the battery to the positive terminal of the coil. Then try to start it. This will eliminate a lot of areas that may be causing your problem. If it starts you will have to remove the jumper to stop it. Also don't leave the jumper in place without the motor running, you could burn your points. Good luck and Happy New Year.
 
Thanks Rhody, I'll give that a shot today and let you know if I get it to start, or (with my luck) if anything blows up!! :smile:)
 
Ok, so here is what I just did.... Placed a jumper from Pos. Bat to Pos. Coil and turned the engine over. No start. So I thought I would spray more starter fluid down the throat of the weber DGV carb to see if it would start. When I did this and tried to start the engine I saw a lot of the starter fluid vapor being pushed up out of the carb. Anyone know what would cause this to happen? Also, when all this first started, I did see a lot of black soot inside of the carb throats. The majority of the soot was in the outboard throat. Do you think it could still have a timing problem?
 
Now I just checked the compression on cyl. # 4 and there is 0, Zero compression. I am assuming that this the cast for the other three cylinders and is because all the air and fuel is being expelled out the top of the carb and not being pushed into cylinders. How the heck could this happen and does anyone know how can I fix this?? Thanks again for any help!!
 
If what you're saying is accurate, how could you not have major valve problems. Not just fried, but broken. I can't imagine any circumstance, other than the head off the engine, where all cylinders could show zero compression. Are you sure you're checking correctly?

Your car was running fine? Then just quit in an intersection, correct? That isn't a typical symptom of zero compression in multiple cylinders.
 
Take the valve cover off and check for rocker movement on each cylinder. If the rockers on the front cylinders move, but the back ones don't than you may have a broken camshaft. This happened to me on a Datsun 2000. If all of the rockers move check to make sure you have the proper lash or at least some lash on each valve, if you have a valve without lash you may have a broken valve. If you have a valve that has lash all the time, check for a broken valve spring or a stuck valve stem. Pull the plugs and check if the pistons are going up and down, if one doesn't you have a broken rod. The position of the front and rear pistons should match and the center 2 should be opposite, up, down, down, up.
 
Yikes!!! This is not sounding very good :frown: Guess I will start by taking Startech's advise and check the rocker and Cylinder movement. Then I guess if I don't find anything there it is off with the head!!
 
Not trying to be alarmist. Just trying to rule out items and narrow down your problem.

What were the compression readings on cylinders 1,2, & 3?
 
I took the plugs out of Cyl's 3 & 4, turned the crank over by hand and stuck a small inspection camera in the spark plug holes. I could see the pistons moving up and down and one of the valves in each of the two cyl's opening and closing. However there appears to be a lot(I mean a LOT) of carbon build up on the valves. So I guess after the first of the year.... it's OFF WITH IT'S HEAD!!!!
 
Thanks Startech, I have a feeling that there is no compression on any of the cylinders as when I turned the crank at the pulley, there was very VERY little resistance encountered. I'll have to wait and check the compression in #'s 1, 2 and 3 on Sunday. Have to take Daughter and Grandson to airport then off to a New Years dinner. Thank you and everyone else on this forum so much for your help and hope you all have a great New Year!!
 
If you have compression on any of the cylinders than it is probably a cam shaft timing issue. The chain may have jumped teeth. How many miles are on the engine? If the cam is out of time the engine will crank over very fast. Mike Mattingly had an old Plymouth with a bad cam haft gear. The car would start and than quit than restart after you cranked it for awhile. The gear was so bad the chain would walk around changing timing continuously.

Repairing the timing chain is a pretty easy job.
 
Not sure about the mileage. The speedo was showing about 80,000 when I picked up the car last year and the speedo was not workig at that time. I have no idea as to how long it has not been working. However, thanks for the comforting thought that it might be just the timing gear. Guess I'll start with the timing chain cover and look at the gear. Then I just might pull the head anyway and replace the valves and install a bigger better cam. Any suggestions on what cam to use? I am not going to race the little beast..... just cruise around a little and want it to sound really good.
 
This is puzzling. You said that when you rotate the engine by the fan, the distributor rotor turned toward cylinder no. 1. That tells me that neither your timing chain nor cam is broken, unless the cam snapped past the distributor gear, and that seems awfully remote.

You said the pistons come up and down as you crank, so the rods must be OK.

I assume you've been driving the car for quite some time over the past year, and that this latest issue is sudden. I think you also said that the car just quit, so that seems to indicate that nothing catastrophic happened.

This all seems to lead back to your compression issue. Are you sure you have no compression? And when you said there was no resistance turning the crank, were the plugs back in or still pulled.

You mentioned the valves opening. Does that mean you took Startech's advice and removed the valve cover to examine the operation of the valves and to confirm your rocker arm is intact.

Again, I could be wrong, but if the car was running fine and then just suddenly stopped, with no earth shattering sounds or effects, I'd stay with the simple things.

Have you disconnected the fuel line at the carbs, dropped it into a can, and cranked the engine and confirmed that the fuel flows strong? Do you know for a fact that the fuel pump is sending a strong flow to the carbs?

Are you certain that a seemingly good wire at the coil isn't actually broken and just intermittently working? Have you put a test light on those wires and then wiggled them to see if the light flickers?

Is it dry cranking strong as if it wants to start?

If none of those rechecks cause concern, maybe you could suspect something in the timing cover, like maybe a cam issue, a jumped chain or something like that, but I'd go that route only after eliminating the easy things. Don't assume you're getting fuel properly without ascertaining that the pump is pushing a strong flow of fuel and that nothing is impeding proper functioning of the floats.

Good luck and keep us posted. Happy New Year.
 
Let me see if I can answer all the questions....
1) I only checked no. 4 cylinder with a scope and the piston moved up and down when the crank was turned at the pulley. I still have to inspect the other 3 cylinders.

2)Have not driven the car a lot and it has been sitting for the last 3 - 4 months since this happened.

3) I checked the compression in No. 4 clyinder only so far. Zero compression regestered when cranking the engine with the ignition and throttle wide open. Still need to check the other 3 cylinders.

4) Very little resistance when turning the crank with a socket at the crank pulley with all 4 plugs completly installed.

5) Removed the valve cover and wittnessed all rocker arms moving while cranking the engine. In addition could see one of the valves opening in the No. 4 cylinder with the scope while watching the piston move up and down.

6)So when it quite running, it lost power quite rapidly, like within a block or two. I do not remember hearing any horralble noises when it occurred.

7) Removed the fuel line at the carb. Stuck the hose in an empty water bottle and cranked the engine by the ingnition for a couple of seconds and got about a quarter of a bottle of gas.

8) What wires do I hook up to a test light???

9) Cranking the engine with the ignition is strong. I had the battery hooked up to a trickle charger to assure it is fully charged.

I'll re-check the compression and the carb. tomorrow. I will also re-check the fuel flow again as I just remembered that I had replaced the fuel filter a couple of weeks prior to all this happening. I know I installed the filter correctly as the arrow indicating the flow direction is pointing to the carb. If all this is due to a stupid little bad filter, I will be very embaressed. Oh well, could be a very cheap fix :smile:) I will let you all know what happens.

Happy New Year to all!!
Bob C.
 
We have ruled out a broken rod and camshaft. If the compression test is accurate and all cylinders are zero than timing is the next test to make. This can be done without removing more than the valve cover and plugs.

It takes 2 revolutions of the crankshaft for a power cycle for a cylinder. During that time the camshaft only rotates 1 revolution. At the 1st Top Dead Center you are changing from the compression to the power stroke. Both the intake and the exhaust valves will be closed. The next TDC is the change from the exhaust to the intake stroke. This is where overlap occurs, which means both the intake and the exhaust valves are open at the same time. We can take advantage of the overlap period to check the camshaft timing. If you rotate the engine and stop when the free play between the intake rocker and the valve is gone and than make a mark on the crankshaft dampener at the timing mark/pointer. Continue rotating the engine and stop when play just develops between the exhaust rocker and the valve and make a mark on the crankshaft dampener at the timing mark/pointer. These marks should be an equal distance from TDC mark (0 degree mark) on the crankshaft dampener. If they are not you have a timing problem and will need to remove the timing cover to check further. This could be a chain, sprocket, or key problem.

I would make this test prior to removing the timing cover.
 
I too am thinking it is a timing issue. I can not think of another reason why air and fuel would be pushed up and out the top of the carb when trying to start the engine instead of being expelled out the exhaust pipe. It really seems to me that something is closing when it should be opening and/or visa versa. Thanks again Startech, and I will check the timing as suggested, tomorrow.
 
I'm always learning but I've never heard of a compression test showing zero compression due to anything remotely close to timing. I've heard of blown rings, a cracked block, a severely cracked head, maybe head gasket, or completely snapped valves, but not timing.

BTW, what kind of carbs do you have, and what do you mean by fuel and air spurting?

I don't want to send you on any wild chase, but once I tried everything imaginable on one of my cars. It kept wanting to start, but just couldn't grab. We tried a new distributor cap just for a random try, and the car started up immediately. Whether it was the pin or the wire connectors I don't know, but I'd try just about anything simple based on what you've said so far, and I'd include a hard look at the carbs and floats. Depending upon you car, I'd check the jets and needles and do the basic piston lift and fall check as well.


Also, I'd put a test light on the ignition wire to the + side of the coil, with the ignition turned on; then I'd wiggle that wire and see if you lose power or current. I'd then be sure the lead wire from the coil to the distributor is also intact.

I can't recall if you said you have points, but if so, be sure nothing there melted into a short. The nylon insulating spacer on the pole holding the points must not be melted or allowing a short. You said you see strong spark at all plugs verifying that your coil is working?

Puzzling, but some of the deeper talent here will weigh in and you'll get this solved.
 
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