Technical 361 FE random miss

I am having a random miss on what is probably a bone stock '59 Edsel with the 361 FE engine. It cranks easily and runs fine most of the time but occasionally gets a random miss most often from coast to moderate to hard acceleration. It idles fine at 500. It missed at idle one time bad enough to load up the muffler and blow it out when it fired.
I was shooting for the easy things first. In the past 10 months I had to rebuild the carb and replace the tank. The fuel lines and filter are clean. Replaced the plugs, wires, points, condenser, rotatory ****on, but not the cap, it looks fine. The coil resistor ohms out good and coil is getting 5.8 volts. The dist primary wire is good. The plugs are mostly brown but a couple are getting some soot on them and the exhaust where it hits the ground in the garage is sooty. The timing is spot on 6 degrees and it has a new spark advance.
Two things bother me:
The spark is more purple-red than fat blue and the compression. I might try replacing the coil next.
I pulled the compression and its low, but not low enough to miss-fire I think but would like your opinion. The factory spec is 180 lbs and my readings are as follows first reading and then with a shot of oil: 1 152/154 2 140/145 3 140/145 4 139/144 5 130/136 6 130/135 7 140/142 8 140/146. Using a infrared thermometer on the exhaust manifold, #4 is running a good bit cooler than the rest upper 189 as compared to the others 215 at idle.
I have put about 1500 miles on it since I bought it and it has not used a drop of oil that I can tell.

thanks ahead for any ideas

 

I would be looking at the valve springs or maybe a tight valve guide. The FE engines are good at wearing guides. Compression seems pretty even. If you didn't already, check the compression with all plugs out and the throttle blocked open to get a true unobstructed reading. Also could be excessive carbon build up on valve stems. That temp probe is a great way to check the fire. Being low on that cylinder tells you where to look. Keep digging.

 

Thanks, I pulled the plugs and checked at wot. The things you named sound like a valve job is in order. I was hoping to get away without one till money got better.

 

Check the ground straps. You have replaced all the usual suspects, but it may have a loose ground connection that gets worse when the motor is running and vibrating. Good grounding is critical.

 

Sounds like you've replaced/checked all the common items, but with a random miss, I would be looking at that coil and even the cap. Sometimes tracking inside the cap is difficult to see. With the price of coils these days, it is easy to put off replacement, but if you've never replaced the coil, theres no telling how long the coil has been installed and may be breaking down as it heats up. You may want to consider getting rid of the points as well. I found that my FE's start very easy and run better with some form of electronic ignition, such as Pertronix. You may want to keep the stock ignition, but points do wear and require frequent attention. Not sure what plugs you are running, but I get better performance from the Autolite 45s. Another option is the Autolite 124, but its a colder plug.
Not to say that you dont need a valve job, but I would definitely look everywhere else first. Pulling heads on an FE is fairly involved, not the least of which is getting a good intake seal at re***embly. Your compression readings dont seem to reflect a significant leaking valve as they are all fairly close. A leaking valve or a tight guilde, in my opinion, would not be a random miss, but more of a constant miss. Make sure your ignition system is operating properly before you start going internal. A weak spark to a plug that may be a bit oil fouled from idle operation will definitley cause a random miss. Also, you might want to ensure that muffler didn;t become partially plugged with the little explosion (blow out) you mentioned. Good Luck, FEs rock, they're just a PITA sometimes.

BOutlaw EcoSinner coupe

 

Thanks for the answer. I am running new Autolite 45s. I hate just throwing parts at one, but that is what I'm reduced to now. The spark is just not hot blue like I would expect, but more purple-red. The #4 is the longest plug wire and also the one that I think its randomly missing on. I'm going to get a new coil on the way home tonight and a cap too. I had to replace the muffler completely as it opened it up like a bomb went off. =[

 

Well...I replaced the coil and cap tonight and it ran smoother and didn't miss or burp on a 5 mile ride soooooo I put it away for the day to bask in a small victory. It shows me you can't use a ohm meter to tell anything about a coil. I thank you guys for taking the time to read and make suggestions.

 

Getting rid of those Autolites would be my first step.... They quit being a good plug after Fram bought them. Go to your local Ford dealer and get a set of BF42 Motorcraft plugs (or maybe a BF82; they should have a listing).

A bit of history. When Ford was forced to sell their Autolite spark plug division in the 70s by anti-trust laws (due to having 'too much' of the aftermarket spark plug market share after complaints by primarily Champion), they continued to use Fram-built 'Motorcraft'-branded Autolites in their new cars... until they started getting too many warranty returns from bad plugs. At which point they went back into the spark plug manufacturing business under the Motorcraft brand. Once they got production ramped up enough that they had enough for aftermarket sales outside the dealers, they started selling them in the parts stores. History repeated... they again grabbed a majority of market share, again there was complaints from the 'other' plug manufacturers, and again Ford was told to either sell off the plug division or pull out of the aftermarket. This time they pulled out of the aftermarket, so Motorcraft plugs are very hard to find outside of the dealers. But still the best plug for a Ford.... And even Smokey Yunick preferred them in his Chevys.

 

Putting a pertronix ignition in my 62 390 FE MADE a world of difference.

 

If you ever take your heads off , look closely at them !!
In 1959 ford made the 361 edsel heads with machined combustion
chambers, one year only deal as it was to costly,
big money heads, don't be talked into a head exchange

 

Thanks for the heads up. =] I read that somewhere but had forgotten it. The car was built April 10, 1959 and I think the motor is original, but don't know how to tell with out some dis-***embly.