Great looking Chrysler. Makes me want to find one of my favorite mid 50's cars, a 57 Desoto. Perhaps it's as simple as a bad plug wire???
I almost tried to go to the Roundup just to see this car. Really love the way it’s coming together good job Danny.
Well I'm sort of glad you didn't! But start booking your trip for next year, the car will be there and you can cruise it.
Man, sorry you weren’t able to make it. Disappointing I know after busting it so hard to get done. Looking good though...almost there! Sent from my iPhone using The H.A.M.B. mobile app
Your inspiration and vision for the Chrysler is amazing. Thanks for sharing. Kudos to all, esp Wife and Dad.
Just read all of this thread this morn...you have luck like mine...in 2010 when I put my brand new '55 Cadillac on the road, I got just 90 miles from home when a rod started knocking in the rebuilt 500" Caddy engine...that put a kibosh on the debut in Salina...fast forward 8 years and I'm building a '48 Cadillac sedanet. It's almost ready for the street. I bought a supposedly rebuilt 350 Chevy engine and had a new 700R4 tranny waiting but I decided to have a friend look the engine over before I put it in the car...he pulled it apart and found marks on the cam bearings (I assume they had to hammer the cam in) , #2 and #4 main bearings had scores on opposites sides and after pulling the pistons to check rings and cylinder walls, found a hole going right into the water jacket-seems .060 over on a 350 is just too much...some people simply have no scruples...so back to square one...!!! Guess I'll purchase a create engine...!!! Thanx for posting your build-Chryslers of that year are one of my favorite MoPars... R-
I still have this stubborn miss that I'm dealing with. I quadruple-checked the firing order, and it is correct. I removed plug wires one at a time to see if I could identify which one wasn't firing. There were actually THREE that removal had no effect on the engine, meaning the engine was running on only five cylinders. So I made a new plug wire and installed it on the first 'bad' cylinder. It cleared right up! Ah ha! So I made the rest of the wires, but there are two that still don't seem to be firing - #4 and #6. They're right next to each other, so I was suspecting a head gasket. I then did a compression test, and here are the results: 1 - 120 3 - 140 5 - 135 7 - 135 2 - 125 4 - 120 6 - 130 8 - 120 So with #4 and #6 each getting their own compression values, I am back to checking ignition. In addition to the wires, I added a new cap and rotor. New AC Delco R44XLS Plugs are gapped at .040. I get a strong spark with the plug wire connected to a spark plug outside the engine touching ground. Without a plug, I get a strong spark from the plug wire to a ground. I did try to swap plug wires between 4 and 6, and that gave me a lot of spitting and sputtering, so I know there is some fire. There seems to be a ton of raw fuel being dumped out of the exhaust on the passenger side (where 4 and 6 are). So for now I ASSume the carburetor isn't a problem, and with reasonable compression readings on each cylinder, the intake and exhaust valves are opening as they should. I have an old style Petronix unit in the distributor. I have read here that the magnets that trigger them can be out of alignment so I'll be checking that next. If any of you smart folks have any other suggestions, I am all ears. I added a video so you can hear this thing sounding like an old tractor. Plus a few pics from last night's test drive for your trouble. Thanks.
The fact that you get "spitting and sputtering" when you reverse the 4 and 6 plug wires tells us the plugs are firing under compression. Therefore, ignition can be eliminated UNLESS there is a problem with the pertronix. I think I'd be looking closely at that.
Try the old deal of spraying carb cleaner on the intake gasket for those cylinders, and at the base of the carb. Look closely for any vacuum ports that could leak around those runners or on the center of the carb. Fire extinguisher at the ready for this! You can use a propane torch with a rubber hose attached too, but I always had more luck pinpointing leaks with spray cleaner. You have a dual plane intake per this pic on pg. 4. It's doubtful the right side of the carb is completely FUBAR, otherwise 1 and 7 would also be missing, but try richening the carb a bit on that side too. Spray a bit of cleaner directly into that side of the carb. See if it picks up. A Vacuum gauge might help diagnose the problem. Plenty of vids on this too. also, running compression http://imperialclub.com/Repair/Engine/dynamic.htm As a last gasp, pull the valve cover on that side and watch the rocker arms for all the cylinders and compare to the 4 in the middle. Is one noticeably moving less? It will still provide cranking compression, but will misfire.
Thanks for the tips. I'm hesitant to go spraying carb cleaner all over my freshly painted engine, but I think I can nail down a vacuum leak in other ways. I don't know that I can richen one side of the carb more than the other but I'll take a look. If I don't find a problem with the Pertronix I will run a dynamic compression test and check the rocker arm movement for any bent push rods or flat lobe or something.
Yeah, I'd cringe too spraying that pretty motor, but light misting shouldn't be too bad. Since swapping the 4 and 6 plug wires caused havoc, I'd assume the ignition is pretty close. You can mark the balancer every 90 degrees from TDC and check the timing alignment of each cylinder. If you have access to a dial back timing light, set it up on #1 and roll it back to zero. Move the spark pickup to each wire and check they are all at zero/one of the 90 degree marks. Did you know #3 on air cooled v dubs was retarded from the rest? Useless trivia for a V8 head, but there you are... Make sure the coil is connected properly (polarity and tightness). That more often affects heavy load and high RPM, not idle, but make sure. Spray carb cleaner (quick, easy - might rinse off the paint!), slowly cover the front right venturi with your hand or a rag (provided the choke isn't blocking this), adjust the idle mixture screw out a couple turns. This is only at idle for testing, it doesn't take much. I'm not suggesting rejetting...
You could try a little propane torch (unlit of course) and just direct a little raw propane toward the manifold gaskets. Kind of like a poor man's nitrous.
Just found this build this morning, outstanding work! Will be watching as you finish up. MoPars rule!
My guesses: Vacuum leak, or the pertronix. I've read so much weird stuff about those pertronix units because I had one in my SBC in my 40 Ford that would act weird. I wish I could be more specific about acting weird, but I don't remember. Also, how far did you disassemble the engine to paint, etc? Did you pull the intake? I always am suspicious of my own work so I check everything I touched if it worked fine before.
I'm stumped. Starting fluid around the #4 and #6 did not affect how it runs. Swapped plugs from other cylinders to #4 and #6, no change. Checked the plug-side crimp on #4 and #6 plug wires, no issues there. Swapped other plug wires to 4 and 6, no change. Stuck the timing light on the #6 plug, which happens to be the 5th in the firing order, which means you can check its advance setting at the balancer. It is at 10* btdc, just like #1. All 8 plugs show to be firing with a light. Yanked the valve cover and verified no broken springs, and intake and exhaust rockers on 4 and 6 are moving. Rechecked compression in each cylinder. Getting 155 in 4, 160 in 6. Help me, how is it possible to have verified 155+ in a cylinder, verified spark at 10* btdc, without lighting the hole, with enough fuel in the exhaust to run you out of the shop? Friend is suggesting a weak valve spring. Does that even make sense? The last thing I want to do is tear down the engine on a wild goose chase. I guess a cylinder leak down test is next? I'm at a complete loss.
If you're getting 155#, I don't think a leakdown test is going to prove anything. Can you beg, borrow or steal another distributor?
I'll throw this one out there... Maybe an internal leak in the intake manifold? If there's a crack into the intake runners from the exhaust crossover, you may be contaminating the fuel charge. Long shot to be sure...
Here's a LONG shot. Common firing orders: 18436572....18736542. Notice the sequence of 4 and 6? Are you POSITIVE you have the firing order right?
You guys are awesome. Thank you for all the suggestions. Steve, your post made me look over every inch of the intake, and you'll never guess what I found - an open 3/16" pipe threaded hole in the intake! I capped it with a plug, and whaddya know, the car runs like a top. Many thanks to you and everyone else that offered suggestions! Now to get back to fixing up this old Chrysler...