'53 Ford 8BA - misfire & rough running - getting worse

[RuralTowner]

Apologies for the long winded-ness.

Have a custom body vehicle my dad put together in the 60s from a couple early 50s Ford coupes. The engine is an original 8BA flathead that has never been opened. Water outlets in front of head...dizzy in front of passenger head. Driven steadily off & on until parked in 1981. Got it running again in 2016 w/ new plugs + cap + wires. Rebuilt ignition system. New coil (old had separated) + condensor & points-to-coil lead as the wire insulation had rotted. New oil. Had a bad miss on #2 (no compression) from sitting so long but an accidental massive dose (thought the new fuel tank had gas in it) of MMO freed that up. Turned the sediment bowl RED! Carb was rebuilt by a member here I believe...ran almost perfect. Added a head-mounted bypass filter type (used the small 3-bolt type instead of the head bolt mount) that would've been optional as it didn't have any filtration. Also set it up with a functional bath air cleaner as the original had gone missing. Unfortunately other non-motor issues & RL saw little further progress.


Fast forward to few months ago finally wanting to get it on the road. Though still had fresh oil wanted to drain in case the last batch had did any cleaning. Put in 4qt Rotella 15W40 + 1qt Lucas Stabilizer. Put proper length plug plug wires on. Carb rebuilt again after 7 years modern gas turned it to gum again. It had developed a new misfire @ #6 from a bad plug. Changed out the NGKs put in previously for new set of Champion H10s. Miss gone. Manifold vacuum @ strong 22-23 @ idle but would get small irregular drops to 20-21 likely from that #2 valve from before. Test drives back & forth along rural road block near property & get popping. Check points & gap was too tight. Reset using piece of box from spare coil. Was running great.

Proceed with low speed laps around block near property (2 miles around) then 3rd lap in 3rd gear & start pushing speed to 40+ mph develop a miss + popping. Temps rise to push 200. Get back & douse the rad to get temps back down. Rechecked the points gap & noticed armature was deeply pitted & base looked to be burned through (later learned it was a ventilated type to explain that look). Replaced points & reset gap. Seemed to run even better. Do the laps again & once again starts misfiring//popping bad followed by temp rise. Get back & coil is too hot to touch. Shut down & won't restart.

Next day starts cold but ran really rough. Checked voltage @ coil (external ballast resistor type) & would get 13.7v when given throttle. Too high. Engine off. Change to a new spare coil that is internal ballast & bypass the firewall unit. No change to running but now voltage @ coil is all over the place. Trace back POS lead to coil & check voltage @ any possible connection. Voltage wildly erratic & engine still running rough. Disconnect generator from ignition system in case of voltage issue. No change in running. Decide to bypass entire onboard ignition by running jumper from BAT POS straight to coil (ignition lead removed). No change. Went back to the LONG plug wires too. No change.

New points rechecked & they had closed up despite tight screws. Replaced points & condensor as the former had excess slop on the pivot & wasn't sure (at the time as it had been awhile) if the condensor was faulty. Slight improvement as this time the points armature didn't have a puny contact & had firm movement. Still runs terrible. Has to be given at least half choke to stay running despite going through carb AGAIN & checking for vacuum leaks. Plugs (not 10 miles on them) cleaned of any deposits (does have signs of running rich despite 1-1/4 turns on mix screws) then regapped to 030. No significant improvement.

Engine runs smoother (still not great) w/ plug wires either held just clear of the cap or (easier to do multiple cyls) if a gap is left between plug boot & plug itself. If do it to entire driver's bank runs "okay". Goes back to really rough when wires fully seated.

Needless to say this is frustrating. Earlier in the year would occasionally start it up & though being gummy (prior to cleaning) it would start & engine would ROAR (the good kind) w/ throttle. That was w/ the universal long plug wires & straight weight oil (was either 30 or 40). Everything started out great then has progressively gotten worse. Mechanically the engine has not been touched. Even distributor timing has been left alone as there was no indication it had to be touched. Alot of the current running issues seem to point mostly to the ignition & partially perhaps mechanics. Cylinders that had previously seemed fine...pull the plug wire & get immediate results now may or may not do so.

Did a compression check & yes the thing is in need of being through. Had consistent 20 pound increase between DRY & WET tests. Cyl #2 still an issue as get more popping out the exhaust since it had the lowest read.
No idea how often the oil had previously been changed or how long it was missing the air cleaner prior to being parked in 81.

[RuralTowner]

Was hoping perhaps this thing would work fine as is. Back in March it was running good when brought it to a militaria show since the body was built to resemble a half-track but has tandem drive. But sitting for ~7 months again did it no favors.

I'm not against giving it long over due attention but am after input on what others may think is up with the ignition system based on description. Steadily worse running. High temps preceded by misfire//popping. Followed by further rough running made smoother by adding extra spark gaps even when points are set. Again engine timing has not been touched as it had previously showed no signs of having needed it. Unless perhaps the nylon timing gear is suddenly showing signs somehow?

[cadillac512]

Holding the plug wires back to increase firing voltage points to fouling spark plugs. There have been many issues...maybe the plugs got too carboned up and need cleaning.
The point gap closing up is normally wear on the rubbing block where it contacts the distributor cam...is it lubed?
Finally, the coil voltage should be pretty steady on the battery side. An analog meter works far better than a digital to test it.
As for having to choke it to make it run better...that's in the carb. Maybe one side of the idle circuit is plugged. It can be a bear to clean after getting gummed from sitting. Have to trace and clean every circuit and passage including air bleeds.


Terry

[RuralTowner]

I had completely drained the fuel system & purged old gas from the lines before priming w/ fresh before running it again. The previous NGKs had ran good but had clearly fouled. The "dead cylinder" one had serious fouling. Confirmed that one when swapping from #6 to #5. The Champions is what I was running for the last few good laps before all this current mess. Had a few gallons of fresh non-ethanol gas in the tank & to try to clear up the slight miss it's had since '16 I put a bottle of MMO in (turned the fuel yellow). Being rather slippery it's possible it might have put a film on the plugs.

The cam lobe is lubed. Put a dob of grease on the finger & applied thin layer while jumping the solenoid. The current set of points...new & not driven on yet only run attempts...that replaced the sloppy ones (used during the "good times" has a felt pad for infusing w/ oil.

Since that 1 time finding the point's had closed up I've made sure the screws are good & tight. So far they have been keeping their gap. A firm 016 gap using feeler drag w/o opening the points further. Have NOT however went from lobe to lobe to be sure.

So far have systematically replaced the condensor then points then cap to no only minor avail. The reason for the cap is the spots for the driver's wires had a white powder come out when I pulled the wires to troubleshoot when all this started. Could pull an end & hold while watching it fire which would smooth the engine out then roughen up after insuring wire again. The ends of the wires are partially blackened while the passenger bank ends are still shiny. I had suspected that MIGHT have been from soap residue left on the ends when putting the boots back on after having fed the wires through the 2 "4-leaf-clover" guides. The previous LONG wires w/ shiny ends didn't make a difference hence the new cap...which did almost nothing even with new cap w/ shiny wires.

Am suspect on the volt meter. Digital test light which is what initially showed me steady 13.7 on the POS side of coil after throttle. After replacing the points it was never steady again even after cleaning up the mounting surface for the points. The chaos of the voltage changes fried the tester. Left me using digital multimeter which is even more chaos.

Entirely possible something is still plugging the carb even though I've had it off 3 times & completely disassembled except for the accelarator pump check ball & spring since I don't have anything that can easily get down there. Sent 2 cans of spray through every orifice & the accel pump works perfectly. Could be junk in a passage. What I should probably do is try cleaning again combined with compressed air through it.
I have an inline filter before the fuel pump but did find "floaters" in the carb bowl during 1 of the tear downs so something had come OUT of the pump from sitting.

Last night w/ all 4 wires on the driver's side just barely engaging on the insulator to leave a gap for the spark to jump it smoothed out enough was eventually able to fully open the the choke. Would die after a minute or so.

[Alaska Jim]

verify that the spark plugs firing order is correct. this could be the misfire problem, but probably not the temp. problem

[tubman]

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Could be the condenser. They can be bad out of the box these days. Get a couple of quality condensers (Std Ignition products from NAPA). Try 'em all and see if one works.

There are others available; a search here will reveal the good ones.

[RuralTowner]

Plug order is correct. Every time I've done anything with the wires they would get changed out 1 by one or in the event when all were off had a paper on hand with the order then rechecked before cranking. After the bad running began the condenser was replaced (as mentioned turned out it was) since wasn't sure if I was still running the original or not. No noticeable change. But agree the replacement could be bum already. They're inexpensive enough to get a couple to try then.

[slowforty]

Does it have an ignition resistor? i had one that went bad intermittantly and drove me nuts trying to diagnose the issues.

[Ken/Alabama]

Have you looked at the wire underneath the points plate inside the distributor? The insulation gets old and cracked causing misfiring.

[cmbrucew]

Have you looked inside of the dist cap for carbon tracks?
Bruce

[RuralTowner]

As set-up it had a ballast resistor with a coil that required it. At onset of the worst symptoms of late I was getting full battery voltage on BOTH sides of the resistor instead of 9v on the coil side. Switched back to the internal-ballast coil didn't change things including bypassing the external resistor. Went BACK to original setup then suddenly the external resistor started reading proper somehow including a "more stable" set of numbers @ the coil w/ multimeter. Need to pick up an analog.

Cap was clean. Since a few of the sockets were oxidized with powder it got changed out for another new. No change in running & still no carbon tracks.

I had replaced the wire leading from the points to the coil. Have not looked closely at the ground wire below it that attaches via eyelet that the lower screw of the condenser also goes through that would ground the plate.
NOW THAT does remind me that when checking the previous sloppy points set that replaced the old pitted ones & trying to manually operate the points & watch for spark. There would be nothing when opening//closing the points then accidentally touched the screwdriver used to move the points armature to the rotor lobes...got a spark. Repeated just opening//closing points & then nothing then grounded it to rotor...spark. After that tried to clean the plate surface & tighten the screw further but if the PLATE isn't getting consistent grounding that would cause issues.

Found a potential means (3 different sources showing same results) for testing the existing condensers on hand since will be a couple days before can get to a parts store. Uses a combination of using a tester first set to OHMs then to VOLTS. Have a new set of points...never used...hiding in the tool box to start with.

[jplutz]

RuralTowner, as to the occasional overheating problem, I didn't see a y mention of thermostat degree. I had trouble with overheating occasionally also. Especially at cold startup. Thought it was a stuck thermostat. It turned out I had NO thermostats at all. A previous owner removed both.

I installed 180deg. units on both sides and replaced the radiator cap with a new 10lb. unit from C&G. That resolved the overheating and I was no longer spitting antifreeze out the overflow tube. The pass side thermostat opens later than the left because of the heater circuit, but that does not effect performance.
Considering the age of the original mods, you might want to check your hoses and thermostats. One other thing, my previous installed upper hoses were ribbed with wire backing. They looked good outside, but the wires were rusted out and some pieces were missing. It's an age thing. I also replaced them at the same time. JPL

[RuralTowner]

Haven't had a chance to get anything done since last post. Events at work over this past week.

There are no thermostats. Cooling system is currently full-flow. Engine is being run (attempting to anyway) as it did for decades prior to original parking. Despite this being in SouthWest AZ. Alot of older vehicles (80s & older) it's fairly common practice to just remove or gut them. The recent temp issue I get seems to start AFTER the misfires begin. All hoses were replaced...both top ones are the ribbed type & one (drivers) does seem like the coil is disintegrating already.
HOPEFULLY in the next few days I can get back to further troubleshooting. One thing I'm going to try is running a dedicated ground to the point's plate. During operation that plate will move around & it's possible the ground wire isn't making good contact below now.

[Don T]

Do not skip Ken/Alabama's suggestion, that wire and how it moves can consistently make the engine run inconsistently. You will never get a correct reading from a digital meter when the engine is running. If you changed the primary wire from the coil to the distributor it is possible to inadvertently disturbed the insulated connection inside the distributor, it is worth checking both items.

[RuralTowner]

At this stage I completely agree with the ground-to-plate being the most likely culprit. Mechanically the engine should run. Cylinder's that ran fine before aren't now. Issue can only be in the ignition.

When originally replaced the points-to-coil & condenser only the nut on the point's were touched. The hold-down screws were left alone until only recently done when was checking gap after seeing they had nearly closed. Any issues with grounding will have started only after that. The new points having no-fire followed by a cleaning of the plate then being sure the hold screw w/ wire being made tight followed brief GREAT run being the last hurrah of a GOOD ground.

Shortly here (no pun) will find out. Will run that plate-to-battery jumper as a proof test.

EDIT: Wire (stranded 12ga) from dist body to plate had no insulation but was completely intact. No wear-through or breaks. Eyelet crimping was way too clean & looks original unlike mine tends to mash but work. Should insulation on it even matter other than abrasion protection? Temporarily removed & replaced direct to battery.
Checked my points-to-coil wire in case somehow it had worn a hole where it goes through the dist body. Wire insulation perfect.
Only to find out the battery was only good for a couple cranks after all the other tests. So it's on the charger until can get back to it tomorrow.

[RuralTowner]

Jumper ground straight to plate made no difference. Ran exact same w/o jumper so no dedicated ground to plate. A test still get a spark (cranking & holding coil lead from a ground) that when started I could widen the gap to a good 1/2in wide. Close is is bright blue small spark that will become a long blue streak.

Also a couple times when setting up the above.. rub block was on the flat turning the rotor (by hand) back & forth just on gear lash it was enough to crack open the points. Other flats the small movement wouldn't but also would have LESS lash. Tested that tester set to continuity.

Then go back & double check things AGAIN after crank. When doing the dizzy dance to get the rub block on a lobe I had to turn engine CCW (by hand ofc) & heard a small "clunk" near the front of the motor. Turn CW a ways then back a ways then back CCW. No clunk. Odd.

Beginning to wonder if perhaps the cam gear which doesn't have metal teeth if factory...MAY have developed a problem? THAT TOO could cause irregular ignition timing. Gear wear would make the timing later...and later. When I DID get it running which requires lots of pumping the throttle & holding the start button (found my remote start) for several long seconds now there is even more engine vibration than before that only smooths (barely) by pulling back the plug boot.

If the nylon gear is going that clunk might have been a stripped tooth barely engaging. Trying to run is only getting worse & worse. Due to the popping out exhaust I was experiencing even before the rabid case of missing after warm up...I was already deeply considering doing an in-frame rebuild. Not in the budget for having the cylinders professionally bored but rings//rod bearings. Check the mains. Rebuild the valves & lap the seats. Do timing gears. Time to stop wasting time chasing an electrical gremlin that might not actually be there. I just hope as many (all would be great) of the HBs cooperate as possible.

[jplutz]

RT, Didn't know you are in AZ. The thermostat use is much more different than in NY. Back in the olden days, (1969-70) I lived in Tucson, and hung out with some guys that drove the dirt track oval south east of the city. The track name escapes me. They used large washers, and experimented with hole size to regulate engine temp on and off the track. As you say the problem starts after the miss fires.
After reading all the things you tried, to solve the problem, IMHO, you may be a candidate for the SBC modified distributors that are made here on the east coast. I don't have one, but they sure get good press on this forum. JPL

[RuralTowner]

I'll look into the dist. In some of my troubleshoot searches I cam across mention of the SBC style...might have even been on here.

Have come across mention of large washers as coolant flow regulators.

And yes the temp rise issue began only after misfiring began usually after reaching around 180. As simple as the ignition is on these...this is the 1st time I've had even remotely this level of headache.

Picked up another condenser on the off chance the other 3 I have in use are potentially at issue even though I can get the spark to consistently jump a large gap. To remove even the possibility that the plugs may have somehow gotten a spark-defying film on them from the big MMO dose meant to loosen a suspected valve I picked up a set of Autolites. Plugs are the only thing in the ignition system unchanged. Hopefully in next couple days will get the chance for 1 last go.

If the ignition issue can be resolved & it returns to operating NORMAL (it still has plenty of pep in it) then I can live with a little popping out the exhaust. Though will probably still have to pull the head or at least the intake to make sure no sludge has found a home in making the #2 exhaust not quite fully shut.

[tubman]

While washers may be the ticket for racing on a roundy-round track, you'll be much better off with quality 180 degree thermostats in a street driven engine.

[RuralTowner]

Not exactly a street vehicle although it certainly can. Be an an eye grabber that's for sure. Mostly saw unpaved road or offroad travel from original build in the 60s up to the end of the 70s. Built on the chassis of one complete 53 COUPE w/ body removed then a bit of frame + axle of a 2nd added to the end.

It was driven all over the desert here & even the Glamis dunes w/o a problem.