EmTee Posted June 1, 2022 Share Posted June 1, 2022 The hope, of course, is that it turns out to be something simple... 1 Link to comment Share on other sites More sharing options...
lancemb Posted June 1, 2022 Author Share Posted June 1, 2022 2 hours ago, EmTee said: The hope, of course, is that it turns out to be something simple... Indeed...Smartin convinced me to check out the ballast resistor, so I'll do that and I'll do some more circuit testing while it's at home and not stuck somewhere. I only hope I can run it enough in my garage to test it, as previously I could only get it to fail when driving. It seems to be getting worse though, in addition to the added ambient heat of the season adding to it, so maybe it will be easier to make that determination. 2 Link to comment Share on other sites More sharing options...
EmTee Posted June 1, 2022 Share Posted June 1, 2022 Actually, you might consider removing the ballast resistor to test it. Check it with an Ohm meter cold; I expect it will pass that test. Next, heat it up. I'd probably sit it on top of my toaster and cycle it a few times. When it's nice and hot, check the resistance again. I used this method to check the choke assembly on my '38... P.S. Don't tell your wife... 4 1 Link to comment Share on other sites More sharing options...
usnavystgc Posted June 1, 2022 Share Posted June 1, 2022 4 hours ago, EmTee said: I used this method to check the choke assembly on my '38... I love innovative ideas like this. 1 Link to comment Share on other sites More sharing options...
lancemb Posted June 3, 2022 Author Share Posted June 3, 2022 (edited) Well, I did some stuff today. First, I removed and checked the resistance of the ballast resistor cold compared to a new one; they were pretty close. Then, I laid a piece of foil over the toaster and heated both up a full cycle with the coil side down. They were both probably toastier than they would normally get. Again, both tested similarly to one another. Note: I obtained a new front harness set from YnZ during restoration of this car because someone was selling it leftover from a project never finished. I didn't install it because I was already mostly done with that portion of work on this car and thought mine was okay. Next, I tested resistance of the segments in the circuit on the front side of the firewall. All were higher than same when comparing to the new harness. However, nothing was extraordinarily high by itself. However, the segment coming from the battery junction going to the firewall connector was easily the highest. Since the harness containing most of the ignition circuit is all under the hood, I swapped it out today, hoping that the sum of the extra resistance could be causing my problem. While I was at it, I put the new resistor on as well for good measure; it was an authentic NOS Delco one and the old one was aftermarket so I figured I'd increase authenticity at the same time. I started the car and let it idle in my garage until it reached full temperature and then backed it out into the driveway. Once outside 10 min the temperature climbed a little past the "N" on the gauge; it was in the 70's in the shade and the sun was hot beating on it, so I think that's pretty typical with no air flow. The car seemed fine otherwise though, but I'm not convinced as I've never had it fail just idling previously. I'm not sure where to go at this point as I'm afraid to take it on the road again and get stuck. If the failure is related to the number of times the ignition system fires per minute then the problem may still exist. Edited June 3, 2022 by lancemb (see edit history) Link to comment Share on other sites More sharing options...
NailheadBob Posted June 3, 2022 Share Posted June 3, 2022 I like @EmTeetest with the toaster to verify resistance changes from cold to hot cycles, good idea you had to perform the resistance value test on the harness, with the higher resistance is a more probable sign that you may have solved your die out condition, but the only way to know is to get out and drive your car, keep EmTee test wire with the 3 foot jumper harness with alligator clips on each end with when you go for road test, it will take sometime of driving to get your confidence back with your car. Bob 2 Link to comment Share on other sites More sharing options...
KAD36 Posted June 9, 2022 Share Posted June 9, 2022 (edited) What was the ballast measurement? “New” ones I’ve measured were high at 1.8-2 ohms. The car will work with that unless other parts of the primary circuit are worn or drift out of spec over temperature, then a weak to intermittent spark could develop due to a “tolerance stack” of worn or out of OEM spec “new” parts. Per the service manual the ballast should be 1.4 to 1.6 ohms, lower numbers drop less voltage across the ballast and can provide the coils primary side with higher voltage and therefore more secondary voltage to the plugs to fire reliably across the plugs air gap. New ballasts can be modified if desired to hit the low end of the service manual specification if you get the wire wound ones that are not fully encapsulated, just clip about 1/4-1/2 inch off (use an ohm meter and mark cut point). If you have or want to keep an original to the car unit, disassemble all the brass connecting swaged barrels and get rid of all the tarnish and crud out of each electrical “interface”. Each is an opportunity for voltage loss. Its ok to jumper across the ballast to see if it affects running, it won’t burn the points short term. Have you tried swapping out the coil with a known good coil - maybe I missed that. If a coils primary (or secondary) resistance drifts while hot or internally shorts under running vibration (which is difficult to measure) the car can quit, surge, idle rough/miss, backfire. FWIW I could not get 2 “new” oil filled coils to last (mounted on its side per stock) more than a few months and the hot run problem would begin to reoccur, but a “new” epoxy filled one has proven reliable. From my research at the time, assumptions on why that worked and the consistency of the newer oil filled coils reliability when mounted on their side is a whole different discussion that appeared laced with strong opinions blended with foggy facts. That plus a corrected ballast resistance value solved my cars hot run problems. (at the time there actually were 3 concurrent issues - bad electric fuel pump, ballast too high, coil performance deteriorating over time at hot). At least by swapping out the coil, it affected (but did not initially fully solve) the behavior indicating the debug approach was on the right track. All this assumes that the voltage regulator is working correctly at hot (both the charging and cutout relays) and the battery holds proper charge. If the battery voltage, or upstream side of the ballast is say 10-11 ish volts measured to ground at idle, in D, full load of lights and fans on its probably not a contributor. Maybe more than you wanted to know but thought to share what was discovered solving a random hot run problem with symptoms similar to your situation. The cars ignition problem was so sensitive it got down to idling hot in D reliably with hood open and slowly stumbling and eventually dying with hood closed and hard starting thereafter - zero fun and tough to cool down in real traffic on 90 deg day. Not saying it’s a smoking gun so apply as appropriate. Good luck and keep us posted. Edited June 10, 2022 by KAD36 (see edit history) 5 2 Link to comment Share on other sites More sharing options...
NailheadBob Posted June 9, 2022 Share Posted June 9, 2022 @KAD36 all I can say is WOW, that is some great information and thank you for posting it, you my friend have a wealth of knowledge and able to apply it in real life car situations, if I ever I should have questions in the future may I contact you? Bob 1 Link to comment Share on other sites More sharing options...
KAD36 Posted June 9, 2022 Share Posted June 9, 2022 Thank you for the kind words - sure and post so we can all learn. My post was a culmination of what some very experienced forum folks helped me to piece together. 100% team effort. Interested to see what lancemb finds… hate these kinds of goofy problems. 1 1 Link to comment Share on other sites More sharing options...
usnavystgc Posted June 9, 2022 Share Posted June 9, 2022 4 hours ago, NailheadBob said: you my friend have a wealth of knowledge and able to apply it in real life car situations, if I ever I should have questions in the future Yes he does have a wealth of knowledge. Ken has helped me a ton dealing with some of my issues. 2 1 Link to comment Share on other sites More sharing options...
lancemb Posted June 10, 2022 Author Share Posted June 10, 2022 On 6/9/2022 at 10:03 AM, KAD36 said: What was the ballast measurement? “New” ones I’ve measured were high at 1.8-2 ohms. The car will work with that unless other parts of the primary circuit are worn or drift out of spec over temperature, then a weak to intermittent spark could develop due to a “tolerance stack” of worn or out of OEM spec “new” parts. Per the service manual the ballast should be 1.4 to 1.6 ohms, lower numbers drop less voltage across the ballast and can provide the coils primary side with higher voltage and therefore more secondary voltage to the plugs to fire reliably across the plugs air gap. New ballasts can be modified if desired to hit the low end of the service manual specification if you get the wire wound ones that are not fully encapsulated, just clip about 1/4-1/2 inch off (use an ohm meter and mark cut point). If you have or want to keep an original to the car unit, disassemble all the brass connecting swaged barrels and get rid of all the tarnish and crud out of each electrical “interface”. Each is an opportunity for voltage loss. Its ok to jumper across the ballast to see if it affects running, it won’t burn the points short term. Have you tried swapping out the coil with a known good coil - maybe I missed that. If a coils primary (or secondary) resistance drifts while hot or internally shorts under running vibration (which is difficult to measure) the car can quit, surge, idle rough/miss, backfire. FWIW I could not get 2 “new” oil filled coils to last (mounted on its side per stock) more than a few months and the hot run problem would begin to reoccur, but a “new” epoxy filled one has proven reliable. From my research at the time, assumptions on why that worked and the consistency of the newer oil filled coils reliability when mounted on their side is a whole different discussion that appeared laced with strong opinions blended with foggy facts. That plus a corrected ballast resistance value solved my cars hot run problems. (at the time there actually were 3 concurrent issues - bad electric fuel pump, ballast too high, coil performance deteriorating over time at hot). At least by swapping out the coil, it affected (but did not initially fully solve) the behavior indicating the debug approach was on the right track. All this assumes that the voltage regulator is working correctly at hot (both the charging and cutout relays) and the battery holds proper charge. If the battery voltage, or upstream side of the ballast is say 10-11 ish volts measured to ground at idle, in D, full load of lights and fans on its probably not a contributor. Maybe more than you wanted to know but thought to share what was discovered solving a random hot run problem with symptoms similar to your situation. The cars ignition problem was so sensitive it got down to idling hot in D reliably with hood open and slowly stumbling and eventually dying with hood closed and hard starting thereafter - zero fun and tough to cool down in real traffic on 90 deg day. Not saying it’s a smoking gun so apply as appropriate. Good luck and keep us posted. I don't remember actually what the ballast reading was, but it was nearly the same as the new one. I did also swap the coil with a new one. I have not measured the voltage coming off the regulator, but have thought I should. It, like all the other wearing components in the ignition system, is new but I know that's no guarantee. Plus, there isn't much left to check. On the items I've swapped, I swapped or compared with new assuming that I don't have 2 bad new components in a row. 1 Link to comment Share on other sites More sharing options...
EmTee Posted June 11, 2022 Share Posted June 11, 2022 16 hours ago, lancemb said: I have not measured the voltage coming off the regulator, but have thought I should. Measure the voltage at the "+" and "-" terminals of the coil both cold & hot. Compare values and report back what you find... 1 Link to comment Share on other sites More sharing options...
KAD36 Posted June 11, 2022 Share Posted June 11, 2022 (edited) If you are interested in investigating the primary side of the ignition and it’s related components and are willing to make a bunch of hot/cold measurements I could dig up my notes, let me know. In Emtees note above if you measure with the engine running you might see the numbers jump around depending on what kind of meter you have as the points are connecting/disconnecting the coils primary to ground. If so you can try it with engine off, ignition on. If you get zero volts just bump the starter until the points close. Edited June 11, 2022 by KAD36 (see edit history) 1 Link to comment Share on other sites More sharing options...
EmTee Posted June 11, 2022 Share Posted June 11, 2022 21 minutes ago, KAD36 said: If so you can try it with engine off, ignition on. That's ^^^ what I meant -- I should have been more specific. Not that it would be fun, but it would be really interesting to see those values when it quits... 1 Link to comment Share on other sites More sharing options...
KAD36 Posted June 11, 2022 Share Posted June 11, 2022 Yeah plus you won’t blink every time the spark hits….as .enquiring minds found out 🤪 1 Link to comment Share on other sites More sharing options...
lancemb Posted June 12, 2022 Author Share Posted June 12, 2022 So, did some more stuff today, and I'm reasonably confident the problem is solved. I worked it all day, so didn't get a chance to see the most recent comments until afterwards. It was a long and eventful day so it will be tough to recount everything but I'll try to walk through the highlights. I had some extra help because Smartin was in town and stopped by to help tweak a couple non-mechanical things, and stayed much longer than expected to help try to work out this issue. I have extra components on the shelf so did some swapping to see what would happen. We were able to get the car to act up but stay running while testing the voltage; this was easier to do with 2 people. The voltage was jumping around all over in the ignition circuit, so we swapped regulators. No change. At this point we decided to swap the ignition switch since there didn't seem to be many options left. When I removed the lower dash panel to get the switch out, I noticed the vent cable had seemingly been routed too close to the terminals at the back of the switch. However, I wasn't certain it was close enough to be causing a short and at day point decided to swap the switch as planned. After putting it back together, the voltage with the car running seemed to be adequate and steady. However, it was still running a bit rough just sitting there, which is not something I'd experienced before. Noticing that the fuel bowl was not staying full, it gave cause to suspect I now had a fuel problem. We eventually determined, after a failed short test drive, that the car seemed to be starving a little for fuel when idling, and starving a lot once driving. Feeling confident enough that the starvation was occurring prior to the fuel bowl, we dropped the gas tank. Since I had a new one I wound up not using on another car, I decided to install it. As it turns out, the sock filter in the tank had become plugged. After replacing the tank, it seemed to run great so we went for a test drive. Everything went great in that short test drive that lasted maybe 10 minutes. So in the end In wound up having 2 things going on, an ignition and a fuel problem. Neither of these issues appeared immediately and the car was running great a few weeks ago, but now it's even better and hopefully a longer test drive next weekend will confirm that there are no further ignition problems! 6 1 Link to comment Share on other sites More sharing options...
KAD36 Posted June 12, 2022 Share Posted June 12, 2022 BRAVO! Saved this for future reference. Thanks for the write up! 1 Link to comment Share on other sites More sharing options...
lancemb Posted June 12, 2022 Author Share Posted June 12, 2022 I still don't know if the problem was the switch itself or if it was shorting on the vent cable. I'll bench test the switch when I get a chance. 1 Link to comment Share on other sites More sharing options...
KAD36 Posted June 12, 2022 Share Posted June 12, 2022 Good. Anything in that primary circuit path that drops even tenths of volts unnecessarily robs the coil. This is an interesting problem. Link to comment Share on other sites More sharing options...
Smartin Posted June 12, 2022 Share Posted June 12, 2022 Sock looked nice and clean, until I ripped it off the tube and dumped it on the floor. I couldn’t blow through it backwards. 1 2 Link to comment Share on other sites More sharing options...
NailheadBob Posted June 12, 2022 Share Posted June 12, 2022 1 hour ago, Smartin said: Sock looked nice and clean, until I ripped it off the tube and dumped it on the floor. I couldn’t blow through it backwards. Great call Smartin, to remove the screen, who would have thought with outside so clean and the inside with so much debris, was all the crap on the middle of the pile on the floor from inside the sock? One would think that the outside of the screen would have some indication a section of it being sucked through, was there an area of the screen that had a crack in it, or either end was broken at the seam where the crimp is at top and bottom or where the mesh was joined together? Either way good call by you to remove it. Back to the electrical testing, I some times use E-Z Hook test leads the have a sharp piercing hook end that is spring loaded to pierce the wire to make good contact to test wires. https://e-z-hook.com/test-leads/ Bob Link to comment Share on other sites More sharing options...
Smartin Posted June 12, 2022 Share Posted June 12, 2022 Yes all of that debris come from inside the screen. I think it was old dried up varnish that finally broke apart when soaked in new fuel. 1 Link to comment Share on other sites More sharing options...
Bloo Posted June 12, 2022 Share Posted June 12, 2022 2 hours ago, Smartin said: Sock looked nice and clean, until I ripped it off the tube and dumped it on the floor. I couldn’t blow through it backwards. Wait, what? All that crap came from the inside? The normally clean side of the sock?! Link to comment Share on other sites More sharing options...
Smartin Posted June 12, 2022 Share Posted June 12, 2022 Yes. My assumption is that the sock was submerged in fuel, and when it finally dried up it turned to varnish. So when it was cleaned on the outside, it wasn't apparent that the inside was caked with crapola. 2 Link to comment Share on other sites More sharing options...
lancemb Posted June 12, 2022 Author Share Posted June 12, 2022 (edited) It's pretty crazy, because it had been soaking in fuel for a long while before the car was first driven, it ran fine for awhile. I'm thinking the new fuel loosened it up, and then the fuel pressure slowly broke it apart until it clogged almost completely. Edited June 13, 2022 by lancemb (see edit history) 1 1 Link to comment Share on other sites More sharing options...
56 Buick Posted June 17, 2022 Share Posted June 17, 2022 On 6/12/2022 at 7:23 PM, Smartin said: Yes all of that debris come from inside the screen. I think it was old dried up varnish that finally broke apart when soaked in new fuel. Asking because I don't know the answer, is a sock required on a fuel pick-up? In other words, could you remove the sock and still run the pick-up without issue? I can understand it will act as a broad area filter (less likely to block) but if it becomes blocked then it is just a constriction to the flow of fuel. Thanks Drew Link to comment Share on other sites More sharing options...
Smartin Posted June 17, 2022 Share Posted June 17, 2022 Pretty much every factory tank had some sort of sock or screen pickup. I guess it’s the first line of defense against that stuff getting into the carburetor, or even into the pump and ruining it. 2 Link to comment Share on other sites More sharing options...
56 Buick Posted June 18, 2022 Share Posted June 18, 2022 Agreed you would definitely need another filter further up the line prior to the fuel pump if the sock was removed. I guess the sock may avoid a blockage of the pick-up tube that may occur - for example, if say a 3/8" piece of debris covered the pick-up tube entry or partially wedged into the opening. Link to comment Share on other sites More sharing options...
56 Buick Posted June 18, 2022 Share Posted June 18, 2022 Best to keep a sock then but bear in mind it can be a source of unseen fuel supply restriction and may need to be replaced, especially when the filter may look clean from the outside but hold such debris inside. Thanks Link to comment Share on other sites More sharing options...
EmTee Posted June 18, 2022 Share Posted June 18, 2022 The sock is a relatively coarse filter. It is there as said, to prevent a large piece of debris from completely blocking the pickup. If there's rust in the tank, enough fine material should still get through the sock to stain the downstream filter media. If the filter is opened-up and examined, it will be obvious that something is contaminating the tank... Link to comment Share on other sites More sharing options...
KAD36 Posted June 18, 2022 Share Posted June 18, 2022 Did that filter start as a 57 thing? 55 just has a big old suction tube like a shop vac. 1 1 Link to comment Share on other sites More sharing options...
lancemb Posted June 23, 2022 Author Share Posted June 23, 2022 On 6/18/2022 at 8:47 AM, KAD36 said: Did that filter start as a 57 thing? 55 just has a big old suction tube like a shop vac. I believe so, and was subsequently discontinued. 1 Link to comment Share on other sites More sharing options...
lancemb Posted June 23, 2022 Author Share Posted June 23, 2022 (edited) As final closure, I tested the ignition switch and it's fine. I couldn't get it to do anything weird, so I'm pretty confident it (the intermittent electrical issue) was just the vent cable contacting the back of the switch, which explains a lot. I figured this as soon as I pulled the panel down and saw how it was laying. The same thing (but other cable on other side of the column) was causing a short and the headlights not to work on Smartin's 58 Roadmaster Piggy when I first got it. Why Buick didn't do a better job (or any at all) of insulating some of those components behind the dash is confounding to me. Edited June 23, 2022 by lancemb (see edit history) 1 2 Link to comment Share on other sites More sharing options...
Glassesguy Posted June 26, 2022 Share Posted June 26, 2022 Saw your car at Lisle on Saturday. Looked great even in the rain. Seems like you and Adam solved the problem. 2 Link to comment Share on other sites More sharing options...
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