It does , just not a coil wire The spring & the carbon / graphite pin under coil to rotor Op said installed another distributor, Still no spark , I would say ground or No 12 volt in crank . Does the rotor turn , as in when you pull cap in different spot after cranking ? If not is it possibly a really unusual issue broken cam teeth ?
Okay so there is power at the distributor when cranking. It’s actually drops from 12v to about 10v while cranking. So what is that telling me? Next going to remove the distributor cap and try cranking it again to see if the rotor is turning. Do I disconnect power to the distibutor when doing that, or leave the pink wire connected?
You don't need to disconnect anything. You really only need to crank it long enough to see if the rotater actually rotates
Okay just checked and the distributor/rotor is turning when I crank the engine with the distributor cap removed.
I think I mentioned in past, I would bench test & not move to vehicle until I was able to get spark on bench ,a Few leads, batt , plug , test light, voltage meter. . You can spin shaft with hand/ fingers , Wants or If spark on bench , Then you know issue with wiring on vehicle.
Points can be bench tested just as ease , Over the years there's been several times I went to go look at a engine a long blocks with a battery starter HEI in hand and a can of starting fluid and tape to start an engine. Tape for no carb , tape intake up Spray with a controlled vacuum leak run off can. Also Times used a Mag
If there is power to the distributor while cranking and while the key on, and all the parts in the system are still good, new and good (which is no longer absolute truth) or has been replaced with good parts, there should be spark to a good spark plug that has a good plug wire connected to good cap plug wire post and the plug has a good ground positioned so you can see the spark. Understand that you are only checking the spark at that one plug and wire, are you cranking the motor long enough to rotate through the complete firing order at least a few times? That spark is going to be a quick snap, then it will be gone until the next time you spin through the firing order and get back to that one plug and wire again. You have stated that the rotor is turning while the motor is cranking, and you have power to the distributor while cranking and while the key is turned on. The only variables left in the system to have a spark is the distributor cap, the rotor, the plug wire you are using, and the plug with its ground. If there in no spark to the plug using this test procedure, something in the system is still defective. Everything needed to create a spark with the HEI system while the rotor turns is in that distributor, except the plug, the plug wire, the condition of the distributor cap where that plug wire is connected to, the rotor condition, and the plug ground. All of these things have been tested except the plug and the wire. The only other quick option would be to use a different plug wire at a different location on the cap and a different plug that still needs a good ground. With power to the distributor and a rotating rotor, the HEI system will deliver a spark to a good plug, plug wire, and plug ground. No spark means something with in the HEI distributor is defective. Even if the timing chain was out of time with the cam and compression, there should still be spark as long as the power to the distributor is present and the rotor is turning. The spark would just be delivered to the cylinder at the wrong time. That could effect the motor running, but not the spark.
I did mention a timing chain in post #12. Others have mentioned a timing chain as well. I had to look back, and sure enough the OP has never said if he checked for a spark or not. He was told how to do so several times, I suppose we have all presumed he did check for a spark. He may have bought a lot of ignition parts when he should have been replacing a timing chain & gears.
OK @4NUTZ have you actually checked for spark by putting a plug in one of the wires and watching it for spark while you crank it?
I used one of these to test for spark at the plug. Helpful when working alone and you can't be sure of a good ground for the plug. https://www.harborfreight.com/search?q=spark plug tester
You can bench test a GM HEI dist by putting 12v to the cap and grounding the body and if all is in working order rotate the shaft and it will be clicking in the cap. The clicking you hear is the spark jumping in the cap.
Sorry guys I thought I mentioned yes did check for spark. I used one of those tester tool things that you plug between the wire and the plug. Got a red spark on each.
Will try to take the timing cover off tomorrow and inspect. Although it might not be obvious unless a tooth is missing, which I guess could happen especially if it’s the factory nylon gears. What’s interesting though is that it drove fine all day all the way up until I pulled into the garage and parked it for the night. When would it have skipped?
they skip when you try to start it. DO NOT TAKE THE TIMING COVER OFF Do this instead. remove the number 1 spark plug. with your finger in the hole bump the starter until you feel compression. turn the engine by hand (same direction) until the timing marks line up. remove the dist cap and see if the rotor is pointing where the number 1 wire is
Factory fiber gears would strip out. The rotor wouldn't turn. Steel might break a tooth and jump time. The engine should still fire and backfire. He has spark at plugs but not firing at all seems strange.
You said definitely getting gas to the carb. Did you give it a squirt of starting fluid just to be sure it's not a fuel issue? Gas to the carb and gas thru the carb experiences can and will vary.... And it'll take five seconds. I always attack the simplest things first. Occam's razor... If it still doesn't fire, I'd do what Moriarty said...
The problem here is that if he has changed the module inside the distributor, and he has replaced the distributor with another, he may well not have the #1 plug anywhere near where its suppose to be. And if the timing chain has jumped 2 teeth, or the oil has been washed off the cylinder walls, the compression could be low enough it may be hard to detect while cranking over. At this point, the starting place may be a compression test on every cylinder, with all the spark plugs removed. That will at least give us an idea if the timing chain is close. If the compression is decent and consistent, he can proceed. He needs to bring #1 up on compression, line up the timing marks and make sure the distributor is rotated correctly to ***ure the rotor is pointing towards the wire going to the #1 cylinder. Then he has to make sure the rest of the wires are going to the correct cylinders in the firing order, in the proper direction. Then before he puts the plugs back in, he probably should squirt a bit of motor oil into each cylinder and spin the motor over a few times to be sure the oil has not been washed of the cylinder walls. Then he can reinstall the plugs and replace the wires. At that point, he can try to start the motor, adjust the timing, and see how the motor runs. There could still be a timing chain issue, if the motor is really weak, or still won't start, the timing chain and gears will be the next step.
Are we talking about a bulb indicator, or actual spark color? Red/orange spark is weak. It should be blue/white. Some cheaper HEI modules dont like to be left ON without running, they'll cook themselves. I didnt read the whole thread, lazy on my part, have you verified that there is a solid ground and bond of the engine block and distributor?
Hey guys, I got sidetracked but wanted to follow up here and say thanks @Moriarity @gene-koning and everyone else that chimed in on this thread. So yeah some of my troubleshooting on this has been *** backwards, and that’s mainly because 1) I’m an idiot, and 2) I have severe ADD and tend to miss steps and forget what I’ve already done, and 3) All of the parts that I threw at it were parts that I had laying around anyway, so it’s not like I was going out and buying all these new parts needlessly and wasting money. And just to take a step back here and give a little more background, this is an old worn and tired engine. It leaks and smokes like crazy, and uses oil. I have a brand new 300cid fresh rebuild on the stand that I’m planning to swap into the truck very soon to replace this old 240. So all the ignition parts that I swapped in are parts that I had brand new sitting in boxes waiting for this new engine. When the thing stopped running a few weeks back, part of me was like who cares I’m pulling it out soon anyway. Then I started thinking well wait, I really want to know why the 240 stopped running before I put the new 300 in. Makes sense right because I want to make sure there are no external forces (electrical issues, etc) that might cause the same no start issue with the new engine. Otherwise I’ll be at square one and going through every possible scenario as to why the new engine won’t run and pulling my hair out. You know just want a good baseline and a clean slate so when the new motor goes in if there are any issues on first startup. So now I’m wondering, and would love to hear what you guys think… at this point should I say screw it and pull the 240 out and throw the 300 in? I know there have been some additional troubleshooting steps provided like checking compression and seeing if the timing as jumped, but if we’ve pretty much ruled out electrical issues or things external to the engine, should I stop wasting time and just start moving on the swap?
Whether you pull it or not check the timing gears. We would like to know if that was the issue. Interesting you tell us about the compression now. That would have helped in the beginning.
I'd get #1 piston at/near top dead center. 1. What do the timing marks show? 2. Is rotor pointing to #1 on the distributor cap? THEN, the question would be what is wrong? Or everything lines up, so why doesn't it start?
At this point, you could just pull the old motor and install the new motor, but then you would have not learned anything, and still have no idea why the motor would not start. As of right now, we have no idea when you actually check for spark through the process, for all we know, you may not have had a spark until around the mid point, so something you may have done did in fact correct the problem, or you could have had spark from the beginning, and the problem is actually inside of the motor. Were I in your shoes, I would follow through with the test procedure I just gave you because I would want to know why the motor didn't start. But its not my time and effort, and its not my project.
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