Finally, a warm weekend at last. I'd like some suggestions for further steps I should take to figure out why I can't get my 48 Commodore 8 started. Here's where I'm at so far:
[b]1. Spark[/b] - the spark looks good after I replaced the coil, points, condensor (twice), rotor, wires and plugs, as well as cleaned and reattached all ground connections.
[b]2. Timing [/b]- I checked the timing several times; it is not fine tuned, but the rotor is in the right spot at TDC for the first cylinder. I quadruple checked that the wires to the plugs are in the correct firing order on the distributor.
[b]3. Compression[/b] - The compression varies from 90 to 110, but I didn't see a suggestion of stuck valves.
[b]4. Fuel[/b] - I need to replace the fuel pump, but it is delivering fuel, and, I can't get the engine going even when I prime the carb with fuel or with starting fluid. This might suggest that the fuel isn't the problem, but I could be wrong. I am working with fresh fuel. I installed a rebuilt carb.
[b]5. Battery[/b] - Fairly new battery, fully charged on my bench.
When cranking, I get a couple of occasional coughs, but nothing more. Last it ran was in November - ran strongly for an hour, but didn't start after that (that may have been caused by condenser failure). This car had been in storage for about 20 years by the previous owner, and I can't be sure what he did when he woke it up.
I'm pretty new to this; I'd appreciate any ideas about what I should be looking at next.
Many thanks, Josh
Try advancing the distributor while someone else is cranking. Maybe you are just a little retarded.. the timing. not you LOL
You may have a fuel delivery problem from the tank to the fuel pump. Try taking a long piece of gas line from the inlet of the fuel pump to a has can with fresh gas and see if it will start. If it does; you have a problem either in the tank or fuel line. I had the same problem and tried the same solutions as you have to no avail. We finally did the gas can trick and isolated the problem to several small pin holes in the gas line that sucked in air and kept it from running.
David,
I think that both may be true! I'll give that a try next weekend.
Thanks,
Josh
Skip, I did a similar test by setting up a small auxiliary fuel tank that I borrowed from a lawnmower. It made no difference.
Josh, Did you check to see if there is GOOD spark from the distributor to the coil , then coil to the spark plugs. Hold the coil wire a bout a 1/2 inch from the block( avoid painted surfaces). Put the car in neutral position & chock the tires. Crank the engine with the Key in the RUN position. Look for a nice blue spark jumping to ground from the coil wire. If a good spark there, remove the #1 plug wire and do the same. This will prove that the spark plugs are getting good voltage, and there is no break in continuity from the ignition system. If no spark with the coil to ground, there is a problem with the coil or distributor... maybe the "pigtail" wire between the upper & lower plates broke, Condenser will cause that also. Do not rule out a bad ignition switch. or a loose wire in the starting circuit. If the plug wire is not passing current to ground , check the cap, rotor, sp wires, etc.
Josh,
At the risk of insulting your intelligence.......
".....[i]the rotor is in the right spot at TDC for the first cylinder[/i]."
The wires are on in the correct rotation, right?
In such situations, my ol' boss used to say, "we must be in Hell.......everything's perfect but nothing works".
F
And when testing, be sure you've got #1 cylinder up on the [i]compression[/i] stroke, not the exhaust stroke.
Last year, were you perchance working with old fuel? If so, remains of that stuff may be mixed with your fresh fuel.
Ron - I've been testing the spark at each plug, and it looks fairly strong since I changed up all those components - I will test the spark the way you have recommended.
Frank - Don't worry about insulting; I've done simple things wrong plenty of times! The wires are set up 1-6-2-5-8-3-7-4, following in a clockwise rotation per the manual. Something is wrong, that's for sure, but not that. I should be cruising down the highway in this baby.
Park - I followed the instructions by feeling when the compression stroke begins, and then cranking it to the U.D.C.1-8 mark on the flywheel. I siphoned it out the old fuel. I made a tool to remove the gas tank plug, but it wouldn't budge and I was concerned about using too much force. If the fuel was the problem, wouldn't it at least start when primed or with starting fluid? All the testing I've done has been with fresh fuel.
All things considered, I still suspect timing is the issue, and I'll have to experiment with that. It thought it was stuck valves, as I had been getting some backfiring through the carb, although wouldn't the compression test rule that out?
I get the feeling that it's the fine-tuning of the timing, that's not quite good enough to get the engine running.
I seem to recall someone saying something like: you get the piston of cylinder one right at the top (end of compression stroke), so the timing mark on the flywheel is just at TDC, then rotate the distributor until you get a spark. Tighten the distributor bolt, and that should have it close enough so that it would run. And then you can do your fine tuning with the timing light once it's running.
Or something like that.
(Note that I have never personally TRIED this......LOL!)
Jon,
I'll give that a try; that procedure is described in the Owner's Manual, of all places. It's worth a shot.
I'm not in the "timing " camp. If it was running before, timed as it is, it should be running now.......maybe not at maximum performance, but it's not causing the problem you're experiencing unless something has changed drastically in that department. Being quite a bit off (5 or 10 degrees retarded) won't make it refuse to run at all, it just won't be right. That much error advanced would make it kick back but I assume that's not your problem.
You said that the rotor was aimed at the #1 position on the cap.......if you were on the exhaust stroke instead of the compression, it would be aimed 180 degrees out. That would be an obvious error.
Q: How "healthy" does your spark look? Blue-white? Just white? You mentioned changing out the plug wires. Did you do [i]all[/i] secondary wires including the coil to cap-center wire? I'll bet you did, but I have to ask.
F
I will test the spark - it looked blue-white at the plugs, but I'll test it with the wire from the coil. Is there a more objective way to test the strength of the spark?
Yes, it was running before, timed as is. However, I have taken the distributor out a few times, but I have been very careful in the reinstall to be sure the rotor returns to the original position. And it did work for that one magical hour afterwards, but not since. Still, I could have messed it up. I will work on the timing this weekend.
Many thanks for everyone's help, here's an update -
1. I tested the spark from the coil, it jumped the half inch gap, was a combination of white blue and red, seemed strong. Same results at the plugs, so I think the spark is ok.
2. I checked the timing, and set the advance based on the method recommended and also suggested in the owner's manual. At 1st cylinder TDC, slowly rotate the distributor counterclockwise until the spark jumps, then tighten the bolt on the quadrant. I checked the firing order, cleaned the plugs...I think I am ok on the spark.
Still no start, but it fired a few times, not enough to get going. I think I am back where I started, fuel issues. The fuel pump is working, so I think carb issues. I am working with a rebuilt carb, but I don't trust the rebuild.
I'm also thinking the battery might be part of the problem. The charge doesn't last long while cranking, so I've got a new one on order.
That's the update, I'm open to any suggestions.
Thanks,
Josh
Welllll, since everything is perfect in the engine, it must be a rat's nest in the muffler. Don't laugh.....I've seen it happen!
Frank
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