Something in the ignition circuit is getting warm and then shutting down. Defective module in the distributor or bad coil? BTW, we are all as frustrated as you. We want to see you driving down the road with a big smile on your face.
Martin '62 Chevy C-10 Stepside Shortbed (Restomod in progress) '47 Chevy 3100 5 Window (long term project) ‘65 Chevy Biscayne (Emily) ‘39 Dodge Business Coupe (Clarence) “I fought the law and the law won" now I are a retired one! Support those brave men/women who stand the "Thin Blue Line"! Hug a cop! USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
Did you check the accuracy of the tab on the timing cover? There are two timing tab/harmonic balancer relationships, one with TDC at about 12:00 and another with TDC at about the 2:00 position. A balancer/timing cover mismatch is not uncommon on engines that have been cobbled together from bits and pieces. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Did you check the accuracy of the tab on the timing cover? There are two timing tab/harmonic balancer relationships, one with TDC at about 12:00 and another with TDC at about the 2:00 position. A balancer/timing cover mismatch is not uncommon on engines that have been cobbled together from bits and pieces. Jerry
Jerry, I hear ya. Best as I can tell you, the engine didn't come with one and I purchased and placed one in what should be the proper location on the timing chain cover. Additionally, when I set the mark right at zero on the timing tab, I stuck a short screwdriver in on the #1 spark plug hole, and could feel the top of the piston. Feels right to me.
Something in the ignition circuit is getting warm and then shutting down. Defective module in the distributor or bad coil? BTW, we are all as frustrated as you. We want to see you driving down the road with a big smile on your face.
This is an interesting possibility. Thank you for proposing something I hadn't thought of yet. However, the second sentence, defective distributor or bad coil might be right, but likely misguiding. If right, I have a defective new distributor. Now, the original HEI I put in the truck was one I bought from pick-n-pull, and it could have failed because it was old, or something (heat, as you mention) could be a culprit. But I can say the new HEI is definitely putting out spark. The only source of electrical is the 12v lead to the distributor, and the output from the distributor to the tachometer. Could the tachometer be backfeeding the distributor? When the truck first starts the tachometer doesn't act properly. It shows extremely high RPMs, possibly double what it should be, i.e. 4,000 rpms shows as 8,000 rpms, which is beyond the range of the tachometer. After a few minutes, it settles down. I think it's a small possibility but it's easy to test, I can simply cut the wire lead to the tachometer.
As for me driving down the road with a big smile, I'm still too nervous. At this point I worry each time I come to a stop light that something might shut down. But I sure get lots of looks!
Try going back to a point-type distributor for diagnosis purposes, or at least an OEM electronic distributor. Those aftermarket HEI's are made somewhere overseas, and they're about as reliable as a promise made by a politician or a used car salesman. At the very least, put a Delco Remy original equipment module in the new dizzy. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
"There are two timing tab/harmonic balancer relationships, one with TDC at about 12:00 and another with TDC at about the 2:00 position."
Regarding this: this 327 has the tab mounted at the 2:00 position. Also, this engine in this truck was running okay before the distributor went out. But, it was always a bit hard to start. I always felt it was a cold start/fuel/carb issue, but all this recent trouble has me questioning everything.
A 305 balancer on an engine with a 327 timing cover ends up with the ignition timing about 30-40 degrees late, and an engine that barely runs.
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Remove the tach wire from the distributor. If there is a short to ground of that wire somewhere between the distributor and the tachometer, it will shut the engine off. If that short is intermittent, it will happen a random times. Some folks have actually used that terminal of the HEI distributor for a theft proof cut off switch. Grounding the Tach terminal will prevent the engine from starting.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
The only way to be sure is to use the positive stop I described and actually check for TDC. In 60-something years of building high performance engines, I've never managed to develop a thumb, screwdriver, or other half-donkey method of finding top center that's accurate enough to believe in. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
I won't be getting back to this for a few days as I am again working going into the weekend. However, that doesn't keep me from doing research. I was just watching the video Jegs put up on YouTube about tuning the Edelbrock 1406. One of the first things I noted was mention of "timed vacuum" versus "full vacuum." Not knowing what timed vacuum is I did some research. Regardless of whatever else might be the cause of the starting issue, it seems evident that I want my distributor vacuum to be coming from the "full vacuum" port on the 1406, which is the one one the driver's side. I currently have it on the vacuum port on the passenger side, which the video says is the timed vacuum port. According to what I have read, this port gives little to no vacuum at idle. Strong vacuum at idle might help with my starting issue.
WRONG! If you're using ported (timed) vacuum you're right. There doesn't need to be any vacuum on the distributor at idle, since the only function of vacuum advance is to help gas mileage at light throttle cruise RPM. As soon as any load at all goes on the engine, the vacuum goes away, and so does the advance. Go ahead and do whatever you choose- - - -at least until you're willing to listen to good advice from people who understand ignition systems. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Enough about TDC already! In lieu of a positive stop device, which I don't have, I again set my mark at zero on the tab and removed the valve cover. I verified that both the intake and exhaust valves were not open. I watched as I spun the motor, saw the exhaust valve open. Just to be sure, I turned the engine over a couple more times, verified intake valve open, close, TDC, (rotor pointing to #1 wire), exhaust valve closed, then opens. Everything looks right, so I buttoned everything back up and it fired up. I let the engine run for a couple minutes, started to get warmed up, I put the timing light on it and set it at 8BTDC. I went to rev the engine, it backfired through the carb, stumbled, and died.
And now, it won't start again. What is really frustrating is how the engine doesn't want to crank at a high speed. It cranks really slow, like there's some sort of resistance. After it backfired and died, it would act like it was making contact with something when turning over. And FYI I had the battery jumped to a running car because whatever this resistance it takes a lot out of the battery pretty quickly. I'd like to start turning this discussion toward mechanical issues that could cause the engine to not start.
Some ideas I'm pondering: do I need a better ground wire from the engine? Do I need to chase a potential starter issue (it's brand new)? Could I have flex plate issue? Bad bearings or rods?
until you find the actual TDC you will never get this thing to start, or run properly. You also need to verify that the spark is actually occuring at the correct time, having the rotor pointing somewhere in the vicinity of the #1 spark plug contact isn't adequate. You were told at least twice how to make an extremely simple TDC checking device. As well as how to use it. Now you are just wasting time, yours and ours. But it seems like you have the timing to far advanced. And the mechanical issue is probably you dont' have the timing set correctly.
I need to ask a very simple question. If the distributor will go in only two ways - 0 degrees and 180 degrees - why is everyone stuck on finding TDC? This is an engine that WAS running, and has been running sporadically throughout this thread. IF I was to do this TDC PSD, what would it show me if it wasn't on the mark? What would it mean for all here helping me troubleshoot if it was correct at the mark? Are we looking for a timing chain that has jumped a tooth (would it even show that)? Would it indicate that the timing tab is in the wrong spot?
I'm just getting theoretical here because I can buy one on eBay and wait for a few days for it to arrive, but I'd like to know how it will help me in troubleshooting before I do. That probably sounds stupid to many, but I've already used many other ways to find TDC on this engine that has been running, so I'm not really sure what the outcome of another timing test will tell me.
Let's suppose, theoretically, something is wrong with the timing and even though it is running at 8BTDC, that's too far advanced and why it backfired through the carb (first time it ever did that). If the timing chain jumped a tooth, that would put the cam out of place, but would that show with a timing test using a PSD? I don't believe it would. Or, what else could it be?
I guess what I'm saying is, in following a troubleshooting flowchart, when you conduct a test with two possible outcomes - yes or no - the flowchart leads on to the next test question. What are the next questions to ask after we answer yes/no on the timing test?
FYI, the distributor will go in place in multiple places not just TDC on compression stroke and 180 degrees opposite. The 180 out comes into play because the timing mark will line up with the pointer at both places. So some folks who think they are at TDC on compression stroke are actually TDC on exhaust stroke.
Martin '62 Chevy C-10 Stepside Shortbed (Restomod in progress) '47 Chevy 3100 5 Window (long term project) ‘65 Chevy Biscayne (Emily) ‘39 Dodge Business Coupe (Clarence) “I fought the law and the law won" now I are a retired one! Support those brave men/women who stand the "Thin Blue Line"! Hug a cop! USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
FYI, the distributor will go in place in multiple places not just TDC on compression stroke and 180 degrees opposite. The 180 out comes into play because the timing mark will line up with the pointer at both places. So some folks who think they are at TDC on compression stroke are actually TDC on exhaust stroke.
I agree with you about the 180 degree thing. That's why I verified with valve cover off to see where in the 4-stroke cycle I was at.
Regarding the "multiple places" of dropping the distributor in, it has a flat bar (keyway) at the bottom that only allows it to drop in two ways. How could it any other?
Oh, and when I had the timing mark pointed at zero on the timing tab and both valves were closed, I placed the distributor in so that the rotor was pointing at #1 spark plug mark.
You can lift the dissy up an inch or so and move the rotor a couple of inches and set it right back down and it will seat. You can do that all the way around back to the original position.
Martin '62 Chevy C-10 Stepside Shortbed (Restomod in progress) '47 Chevy 3100 5 Window (long term project) ‘65 Chevy Biscayne (Emily) ‘39 Dodge Business Coupe (Clarence) “I fought the law and the law won" now I are a retired one! Support those brave men/women who stand the "Thin Blue Line"! Hug a cop! USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
But it has to be ordered, which means I have to wait, which is why I am looking past this troubleshooting step. I will order one, but we won't have answers for 10 days or more...
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
well until you establish TDC and verify the accuracy of the timing marks, you may as well just watch football. Do you have oil pressure? The blade on the distributor drives the oil pump, and it can go literally anywhere. I don't know about the V-8's but on the 6 cylinders, you can get the distributor in far enough to drive the rotor, but not the oil pump. You gonna have to just bite the bullet and check the basics. Just having the rotor pointing in the general direction of the right spot isn't adequate, and the piston somewhere near the top is not adequate. These need to be pretty precise, hence the term 'TIMING'. Once you take the distributor out, and particularly if you use a different one, have turned the engine over with the distributor out, and if you question the accuracy of your timing marks, you HAVE to start at ground zero, you cannot get away from it. Except perhaps for sheer luck.
For the last 100 years or so, the troubleshooting flowchart to diagnose engine issues is: (A) Compression, (B) Ignition, (C) Carburetion.
Why?
Because if the compression is bad, regardless of how many new expensive parts you throw at the ignition, or what brand of shiny new carburetor is acquired, IT WON'T HELP! Then, once the compression is not suspect, a defective ignition will negate any amount of time and or money you throw at a shiny new carburetor.
You did a compression test, and while not great, it should run start and run OK.
So, item B - ignition
The complete ignition system should be tuned TO FACTORY SPECIFICATIONS. Begin with setting the dwell (if you have an electronic distributor, it adds another level of discontinuity). The electronic distributor either works or it doesn't, and without some good test tools, and know how to use them, IMPOSSIBLE to know. And remember Jerry's comment about new electronic distributors being about as reliable as a politician's promise. Go back to basics, get it running, then if you want electronics, so be it. Put a points and condenser distributor in, and set the dwell. Now its time to set the timing. You need to verify top dead center on a used engine (see brokenhead's comment above). You can have as many different positions of the rotor as there are teeth on the distributor! Once you have both dwell (first, always) and timing to spec, need to check the voltage at the plugs. I like to use an oscilloscope, but a lot of folks will just ground a plug to the block.
Once the ignition is very close to perfect, item C - carburetion
I know lots of folks like new shiny carburetors, but ARE THEY CALIBRATED FOR THE APPLICATION? Much better to start with a known original. Go back to basics, get it running, then if you like new and shiny, so be it.
As others have said: if you have compression, and you have good spark, and you have the correct fuel mixture, AND IT ALL ARRIVES AT THE CORRECT TIME, the engine will start and run!
Jon.
Good carburetion is fuelish hot air The most expensive carburetor is the wrong one you attempt to modify. If you truly believe "one size fits all," try walking a mile in your spouse's shoes! The Carburetor Shop
Thanks Jon. I am with you here. I guess I'm trying people's patience. I don't know how to explain this better, but something is WRONG. I posted a video of the engine not cranking correctly. Even if I have timing, compression, spark, air/fuel, if I can't get the motor to turn it won't start. That's a brand new battery, a $200 AGM. Today I'm going to pull all the plugs and see if it will turn ok.
Some have more patience than others. We really want to get you on the road but you seem to resist every suggestion. I watched your video a couple of times. It shows the engine cranking fast enough to start at first then slows down which is normal to a point. Your starter may be dragging more than it should but the only way to test it is with the proper instruments. You put the engine at TDC on the compression stroke, if not exact, close enough to start, and put the rotor pointing to #1. It fired and ran until you tried to rev the engine and it backfired and quit. In your very first post you said the engine had been running fine for several months until the distributor went bad. You replaced the distributor and it again ran fine for a while. The common thread is the distributor. I suggested several posts ago that a component was heating up and shutting down the ignition. I still believe this could very well be the problem. Aftermarket distributors bought off evilbay are notorious for being defective. My final suggestion is to go by your local salvage yard and get a distributor off an older (vacuum advance) GM V8 that is known to run and swap it into your truck. If that doesn’t work swallow your pride and find a real mechanic shop to test everything. Now, like Jerry, I’m out.
Martin '62 Chevy C-10 Stepside Shortbed (Restomod in progress) '47 Chevy 3100 5 Window (long term project) ‘65 Chevy Biscayne (Emily) ‘39 Dodge Business Coupe (Clarence) “I fought the law and the law won" now I are a retired one! Support those brave men/women who stand the "Thin Blue Line"! Hug a cop! USAF 1965-1969 Weather Observation Tech (I got paid to look at the clouds)
Livemeyer, take a deep breath here. Your motor is running badly because something is out of whack. To sort it out requires diagnosis. You cant guess and its not helpful to sort of stab at the problem and speculate. I know you want to get this going but it just will not happen by hanging a lot of parts and turning the distributor in all directions to see if you can get it to settle down. You got some pretty good advice here. Be patient. Get the piston stop tool and determine TDC. It all starts with that. Second, you need a known good distributor with a working vacuum and mechanical advance. And by known, I don't mean one that will just run a motor, but one that will run the motor correctly. As was recommended above, get a real delco. find someone in your area that can put it on a sun machine and confirm the advance is working correctly. Install some nice new ignition parts, make sure the coil is good, and if using a ballast resistor, make sure it is good and of the proper resistance. Once the motor is at TDC, get the distributor in and look at your timing tab. If it does not read TDC, mark it so it does and then you can start moving forward. I know its frustrating, but this is the correct path, you just need to take it and you will sort out the issue, good or bad.
Cheap and almost instant piston stop: 1, old proper spark plug. 2, one long bolt. 3, break the center ceramic out of the spark plug.4, tap the shell inside to fit the long bolt. 5, screw the bolt into the shell with the head where the spark gap used to be. 6, cut a slot in the bolt for a screwdriver. &, install, turn the engine to what you think is TDC. 7, turn the engine backwards to the stop. That is it.TDC is right between those stops.
Sort of like the one I described way back on page one of this novella? Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
Hey! Jerry! back to square one. I remember that way back in this post. This post is longer than a "make a piston stop" tip would be. Of course it won't get the motor running good, but that's for another 8 pages. I'm rooting for TDC to be found someday. You never know. Don't take this the wrong way but I hope he gets his thumb unstuck and uses it on no.1 spark plug hole. Close enough for Government work.
Then: Use the timing light for disco dancing.
Right is right, even if everyone is against it, and wrong is wrong, even if everyone is for it. - William Penn
Sort of like the one I described way back on page one of this novella? Jerry
I thought said you were done... I can't stay away either. I'm pulling for the guy. I still stand by my "1) Drink a beer, repeat as needed", advice offered on page three. It can't hurt, but probably help. Carl
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
Is this going to become a miniseries? "Top Dead Center" sounds like a good title. That way more people would tune in...sounds a little like a spy show, a little like a mystery, a little like a murder, political intrigue, maybe even a ghost story (in time for Halloween).
~ Jon 1952 1/2 ton with 1959 235 | T5 with 3.07 rear end
When in doubt, trailer the thing to the ODSS homecoming. I am sure there will be someone there that can fix it while the rest of us hand tools and beer.
