TJM70's_48 Posted June 7, 2009 Report Share Posted June 7, 2009 While driving tonight at various speeds I experienced a "miss" or very temporary loss of power...kind of a quick bog down with no backfire (or carb backfire). At slow speeds it was enough to jerk the car a bit, sort of like a sloppy clutch release, and at higher speeds it was a momentary loss of power. I've only had the car a couple of months and I'm still getting to know it...but wondered if anyone could help me figure it out. I'm thinking that the logical place to start is with the distributor, wires, plugs...but where else may be a possible cause? And in what sort of troubleshooting order should I go? Thanks, Tom Quote Link to comment Share on other sites More sharing options...
TJM70's_48 Posted June 8, 2009 Author Report Share Posted June 8, 2009 After driving it again yesterday, I'm thinking that it's a fuel related issue. Any suggestions on troubleshooting that area? Quote Link to comment Share on other sites More sharing options...
norrism1 Posted June 9, 2009 Report Share Posted June 9, 2009 Check for a crimpt fuel line. Then check pump pressure if you have the tester. Quote Link to comment Share on other sites More sharing options...
TJM70's_48 Posted June 11, 2009 Author Report Share Posted June 11, 2009 Well, I did some checking today...thought I'd look at the sediment bowl for dirt...nothing there. I mean, really, nothing in there no dirt but also...no filter...isn't there supposed to be a filter inside the bowl? This leads me to worry that my carb is dirty if crap has passed thru the bowl. I still don't have a shop manual, so, I have to ask for pointers on the fuel filter (part number, replacement, how to remove bowl, re-installing, etc). I will also check the fuel lines. It's a new fuel pump put on by the previous owner. I do not have a fuel pump pressure tool. Quote Link to comment Share on other sites More sharing options...
Jim Yergin Posted June 11, 2009 Report Share Posted June 11, 2009 If you are talking about the glass bowl on the fuel pump, the only filter in there is some wire screening up where the bowl fits into the body of the pump. On the otherhand, the old style in line fuel filters with glass bowls did have a filter element in them. Jim Yergin Quote Link to comment Share on other sites More sharing options...
TJM70's_48 Posted June 11, 2009 Author Report Share Posted June 11, 2009 Thanks, Jim. I am talking about the bowl on the pump...I have so much to learn. So much. Quote Link to comment Share on other sites More sharing options...
jpwuertz Posted June 16, 2009 Report Share Posted June 16, 2009 You could check if it is a fuel starvation problem by driving with the choke pulled out a bit. I have a B3B pickup that hesitates when it is cold and pulling out the choke a bit cures the problem. One of these days I would like to get this problem resolved properly, it is on my list of things to do. Jim Quote Link to comment Share on other sites More sharing options...
Merle Coggins Posted June 16, 2009 Report Share Posted June 16, 2009 Jim, that's not a fuel starvation problem. It's a cold engine needing a richer mixuture, normal operation thing. If it runs good after it warms up a bit, then all is well. Tom, I had a similar experience with my truck recently. It was loosing power, coughing and hesitating badly under acceleration, and generally not running well. I found that my points gap was VERY small. I readjusted my points, relubed the points cam, and readjusted the timing. It now runs great. As the old saying goes, "when you're positive it's a fuel issue, check the ignition system." Merle Quote Link to comment Share on other sites More sharing options...
moxieforme2 Posted June 17, 2009 Report Share Posted June 17, 2009 Merle's, engine problem was probably stress- went away after he unloaded that humongous TV! Quote Link to comment Share on other sites More sharing options...
Merle Coggins Posted June 17, 2009 Report Share Posted June 17, 2009 Humongous is an understatement. Quote Link to comment Share on other sites More sharing options...
TJM70's_48 Posted June 17, 2009 Author Report Share Posted June 17, 2009 After giving it some thought and doing a lot of reading, I felt like it must be an ignition problem. I am not a good diagnostic mechanic...I can do the work if someone else helps me figure out what is wrong...but, my diagnostic skills are woefully thin. Anyway, I've only owned the car a few months. When I suspected the ignition system, I emailed the previous owner as he had mentioned a problematic and small miss that was points related. I checked the points gap and found it was too wide...but only by .002 or so. Would this be a possible source for an intermittent problem like mine? Another important question - he gapped the points to .020 and did the timing. Possibly left the lock screw a little loose...if I restore the gap back to the right size (from .022) do I need to recheck the timing? Of course, I need to buy a timing light if that's the case. Thanks, Tom Quote Link to comment Share on other sites More sharing options...
Merle Coggins Posted June 17, 2009 Report Share Posted June 17, 2009 That extra .002" shouldn't matter a whole lot, but go ahead and adjust it if it makes you feel better. A check with a Dwell meter would be a more effective measurement, if you have one of those. And yes, timing should always be checked and adjusted after adjusting the points. Points adjustment will effect timing. And poorly adjusted timing may be part of your problem anyway. Merle Quote Link to comment Share on other sites More sharing options...
Californian Posted June 20, 2009 Report Share Posted June 20, 2009 Tom, just a thought, while doing the electrical inspection was the pig tail wire in the distributor loose or frayed? if it is then it can ground out momentarily when the distributor advances either mechanicly or by vacum... The one place I remember a problem in the fuel system was the flex-line between the fuel pump and the steel line from the gas tank., these lines have been known to swell on the inside and restrict the gas flow was what a friend of mines dad said when he had a Ply convert back in the 50's.. The best test to elimanate anything before the carb is with the fuel line pulled at the carb and a hose on the fuel line directeted to a bottle or can and ignition off out in the open air, jump the starter solenoid with a remote starter switch and spin the motor over and you should get some steady spurts of gas right away, if it acumalates fast then you know your good so far... And you mentioned earlier about a clean fuel bowl could some crud got in the carb , pull the carb air-horn off the carb body and check in the float bowl for crud if you still think its fuel related... Have you checked the compression on this engine dry then wet with a few drops of oil? Keep a journal with some of your findings for future referance..or just do like I learned to do was to write the compression readings on the inside of the hood with chalk... Tom (09) Quote Link to comment Share on other sites More sharing options...
Rdemarti Posted June 24, 2009 Report Share Posted June 24, 2009 (edited) Sounds like points, or possibly the distributor shaft bushing is sloppy maybe? Check the small wire from the coil to the distributor on both ends. Pop the cap and check for slop side to side on the shaft Check the pigtail wire from the distributor housing to the advance plate Clean the points with a matchbook cover and set the gap (the matchbook cover is close enough to run with if you don't have feelers ~.016") Check the condenser screw and clamp, and also the connection to the points Put it all together and run it in the dark. Look for arcing in and around the sparkplug wires and bracket. Hope this helps! Edited June 24, 2009 by Rdemarti Quote Link to comment Share on other sites More sharing options...
TJM70's_48 Posted June 27, 2009 Author Report Share Posted June 27, 2009 Thanks for the pointers, I'll do some more checking. I had it out earlier this week, not a hint of a miss until I had to stop quickly for a fast changing traffic light. Upon the green light, I had a heck of a miss that went from start into third intermittently. Then it went away and didn't return that night for the remainder of the drive...about 12 to 15 miles. Fairly steady speeds (40 or 45) no more quick stops. This got me thinking about the mechanical advance maybe not working properly...and not returning the timing at idle? I do finally have a shop manual. I'm reading and waiting on a new timing light to arrive via the mail. Please keep the suggestions coming. I plan to look into all of them. Californian - I haven't checked the compression...don't have the gauge yet. I've not done much other than brakes, oil, an occasional gas tank or other odd job like a sensor or two, wires, plugs, on my other newer cars for quite a few years...need to stock up on some new "old" tools. Rdemarti - I like the idea of looking in the dark. Hadn't thought of that. Thanks again, guys. I'm open to any idea. Quote Link to comment Share on other sites More sharing options...
TJM70's_48 Posted July 13, 2009 Author Report Share Posted July 13, 2009 Thought it was worth following up to thank all of you for the help. I ended up with no spark and replaced the points and condensor. Voila, started up right away. I adjusted the timing and took it for a spin. A little miss on acceleration in all three gears. Re-adjusted the timing (retarded it a bit) and much better. I took it out for a long ride with numerous hills and some 2 lane highway driving last night and had a nice ride. I'm not sure if I still have a timing adjustment to make or not...as I don't know how much power to expect in any given gear...the car seems to lack power when trying to take a Pennsylvania hill in third gear with a running start. I've only had it for 4 months and don't have anything to compare it to. Thoughts? Thanks, Tom PS - My radio is almost ready to go back in....I just finished rebuilding / fixing capacitors / testing tubes, etc the original Mopar 602 - had it playing for a few hours on the workbench with a new speaker last night. Just have to figure out how to mount the new speaker and a couple other details. Quote Link to comment Share on other sites More sharing options...
desoto1939 Posted July 13, 2009 Report Share Posted July 13, 2009 As the cars get older the breaker plate get older and also starts to wear and you could get some rough engine. A friend of mine had a similar situation. An old time mechanic listend to the engine with a slight miss. We pulled the distributor cap and we were able to wiggle the breaker plate. He told us to replace the unit and this solved his problem. I have spare breaker plates for my car and when I do a tune up I just replace the entire unit since I can set this up with new points and condensor and small internal wires. After taking the old unit out of the dizzy I then rebuild and clean the unit and clean the grease out of the small ball bearing in the upper plate. I alwasy keep a fresh breaker plate in my tool box inthe car. I do my tuneups witht ehdizzy out of the block and mounted in a vise It is much easier to work and you can get a better gapping on the points. These are just points that i have learned over the past 20+ years of being in this hobby. If you need to know what the correct breaker place is for your car or truck write to me with you car/truck info and dizz info I wll try to get you the info my Autolite books goes up to 51. rich HArtung Desoto1939@aol.com Quote Link to comment Share on other sites More sharing options...
norrism1 Posted July 13, 2009 Report Share Posted July 13, 2009 See if it the dwell needs adjusting on the dizzy. Quote Link to comment Share on other sites More sharing options...
TJM70's_48 Posted July 14, 2009 Author Report Share Posted July 14, 2009 I don't have a dwell meter...no other way to check it, is there? Quote Link to comment Share on other sites More sharing options...
norrism1 Posted July 14, 2009 Report Share Posted July 14, 2009 You could rent one free from Autozone or Advanced Auto if in your area. Rent free means buy and get refund when returned. Tool loan is what they call it. Quote Link to comment Share on other sites More sharing options...
TJM70's_48 Posted September 17, 2009 Author Report Share Posted September 17, 2009 Just to update the thread with some results. I ended up putting new points in the car and re-adjusting the timing. Once the points were done, it finally restarted (after not starting at all for a while). Drove fine after getting the timing right...I have limited experience with the timing and not for many years. I still had the most minor, but annoying, miss from time to time...just something sapping the power a little bit. That turned out to be a bad spark plug wire on #4 cyl. It was arcing at the distributor and I just happened to catch it in dim light. Thanks for all the help and pointers in the thread as I continue to get to know my car. Tom Quote Link to comment Share on other sites More sharing options...
greg g Posted September 17, 2009 Report Share Posted September 17, 2009 an easy way to check plug wires it to take a mister bottle and in dim light or after dark, mist around the wires withthe car running. If you get a lightning show you got troubles. Electricity like water takes the path of least resistance and if it finds an easy ground before getting to the spark plug, it will jump early. Quote Link to comment Share on other sites More sharing options...
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