changing plugs every 100 miles!!
 

Hi all...i have a 8ba flathead and i'm frustrated cause my spark plugs don't work more than 100miles +-....!!!i have changed all wires and i put a pertronix kit and new coil from bubba.....but the problem is not solved...for some time engine runs good and than starts to crakle and runs rought....can you suggest me some of the causes?thanks a lot!

Re: changing plugs every 100 miles!!
 

What are the plugs like when you take them out? Is the motor running over-rich? (too much fuel?)

Mart.

Re: changing plugs every 100 miles!!
 

What brand of plugs and heat range are you using?
Ed

Re: changing plugs every 100 miles!!
 

plugs are black with residual of combustion....that's a problem that i have before i put the pertronix kit ,new coil and wires......hey that's a car i buy from a guy in uk some years ago.....is name is Simeon Roberts.......by the way.....when i start the engine i have Always a little popping or crakling.....after some km i notate that the issue became insistent....engine was stock with a 97 now has a navarro intake with 97s ....i buy the new one in uk......

Re: changing plugs every 100 miles!!
 

plugs are ngk b6l....Ed....distr is a mallory with mechanical advance....i read somewhere that this mallory are not well tuned for the flathead....i don't have a kit to register the internal advance....

Re: changing plugs every 100 miles!!
 

If plugs are black it is to rich (fuel mixture) or the plugs are to cold (heat range).

Re: changing plugs every 100 miles!!
 

are you running those little four inch paper air filters? They dont work for long and maybe thats the problem. Maybe try a different brand of plugs.

Re: changing plugs every 100 miles!!
 

i have scoops with screen in the 97s...that's the kit from speedway..

Re: changing plugs every 100 miles!!
 

I had that same problem once. there was a bunch of those china filters that would not breathe. I kept fowling plugs and finally realized that my breather was the problem. switched to K&N element and have not had the problem since.

Re: changing plugs every 100 miles!!
 

The filter screens are the root of the problem.
I just went through this same thing on a friends '32 with 2 strombergs. sooty plugs & ran like it had a bad fuel pump. After much fussing, finally took away the screens & it ran like it's supposed to.

Re: changing plugs every 100 miles!!
 

If the screen removal did not help try NGK spark plugs if your not already using them. NGK offers two heat ranges for the flathead the plug numbers are B-4 and B-6 the B-4 plug is the hotter plug. If your using champion H-10 plugs I gave up on them years ago their made in mexico and and in my opion are junk.
Autolit also offers a plug for the flathead part number 216 its much better than champion but not as good as NKG plugs.

Re: changing plugs every 100 miles!!
 

Ronnie just now i buy a set of 10 NGK B-4L plugs....i choice them since till now i'm using the B-6L that are more cold....thanks for the support!

Re: changing plugs every 100 miles!!
 

42MERC....your friend took away the screens...but what use him for air filter?only the scoops without protection for carbs?thanks for the interest..!

Re: changing plugs every 100 miles!!
 

Let us know how the hotter plugs work. Also interested in the screens issue as I have that setup on an engine I am currently getting ready to run.

Re: changing plugs every 100 miles!!
 

What kind of carb / carb's ?

Re: changing plugs every 100 miles!!
 

[QUOTE=rodderbilly;903180....... now has a navarro intake with 97s ....![/QUOTE]

As he said above. DD

Re: changing plugs every 100 miles!!
 

carbs are 97s big logo on a navarro racing intake.....one is new made in uk....

Re: changing plugs every 100 miles!!
 

I've only ever messed with 94's but some things are universal.

Over rich could be caused by:
Fuel pressure too high.
Needle valve not sealing (debris on seat)
Punctured or damaged float
Fuel level set too high.
Main jets too big.
Damaged power valve (94 only)
Filter clogged.

Mart.

Re: changing plugs every 100 miles!!
 

rodderbilly, Take a good close up photo of each plug tip and post it, if possible. thanks.

Re: changing plugs every 100 miles!!
 

It does sound as if your running too rich. Do you know the size of the jets and the power valves in the two 97'S??? Does the engine use oil?? You may want to contact Uncle Max for his suggestion on jet size, he was spot on for my 2-97's Send him an email or personal message here on the ford barn.

Re: changing plugs every 100 miles!!
 

Not the best idea to be running a racing intake on the street. With no heat on the manifold you are just asking for drivability problems.

Re: changing plugs every 100 miles!!
 

fuel fuel fuel fuel------------too much fuel....................=black plugs.........

Re: changing plugs every 100 miles!!
 

Try .043 jets and .71 power valves if you are running 2 97s.

Re: changing plugs every 100 miles!!
 

i agree Jack....with this intake new plugs the engine needs about 10 minuts to worm and run fine....but when is worm the response is good.....by the way i have the plug problem before i put this intake....thanks for the contribute!:)

Re: changing plugs every 100 miles!!
 

yes deuce i have just ordered ngk b4-l plugs that are a step hotter than the b6-l that i use on the flathead....now i'm ordering .043 - .041 jets and power valves....thanks

Re: changing plugs every 100 miles!!
 

Well...today i tested the coil and i try 2.3ohm on the primary and 8300 ohms on secondary , i have a 1.6ohm ballast in the circuit...meens that in this way i have a weak spark so i should change that ballast with one 0.7ohms of impedence for get 3ohms ? thinking that 8300 ohms on the secondary are a little low?!.......

Re: changing plugs every 100 miles!!
 

With the Navarro racing intake. I ran one on the street, this is what I found works best from cold.
Start the engine, let him run for 2-3 minutes. If it's real cold, you'll see the carbs start to frost. Shut him down. If they were frosty, you'll see them thaw as the engine heat soakes the intake/carbs. Then start him up. And away you go. When doing it this way, the engine ran like a long dog. And would do so for the rest of the day. Only needing the heat soake after a overnight rest.
Bit of a palavar, but work good. Next one will have a heated intake.
Martin.

Re: changing plugs every 100 miles!!
 

Yeah, tooo much fuel to air mix equals black sooty plugs ! Too much fuel, as stated, can be caused by many individual reasons and / or a combination of reasons. Start with the easy things first, i.e.- remove the filters and see if changes or no. Make sure hot spark is present at all times. If sooty, hotter plugs may be indicated to 'help' situation. Then leaner jets , if sooty plugs persist. Any air leaks in intake gasket will mess with mixture settings. Do not get lost in the weeds...first ! Do the simple things and eliminate those first..maybe find the answer therein. Do you have an electric fuel pump (with 2x2, I assume you do?). If so, what is pressure setting pounds !

BTW...this may seem elementary, BUT make a check list and check off 'things' as you go along and like a map will keep you on track and possibly lead to solution. If you are like some of us with older/fuzzy brain cell, maybe helpful :)

Re: changing plugs every 100 miles!!
 

Thanks for the help!now the parts are ordered..i need to wait since i live in Italy and some parts like carb parts need to be ordered in the states!my fuel pump is the stock 8ba ....in the carbs i have only metal screens so the air is free..i was thinking to start with no ballast since i have 2.3ohms in the primary coil.....i need to remove the ballast....by the way first thing i do is to put that ngk b4l plugs ....:cool:......for the carbs i ordered #69 power valves ...some .041 and .043 jets....

Re: changing plugs every 100 miles!!
 

I haven't seen the plug gap discussed as yet but if you are running 25 - 28 thou you should open them up to 40 thou and give it a try. You might be suprised at the diffence. Todays crap gas needs a good wide spark to fire it properly.

Re: changing plugs every 100 miles!!
 

A few things, I'd find a distributor machine and get the ignition sorted out on it and have caution with a hottor plug as they leave more heat in the engine and a flattie can have issues with heat.
You say that you had same problem before the navarro intake, did you have mutiple carbs then? I ask because you say at least som eof the carbs are recent - correct? so the problem might go back to a particular carb? For instance, if you originally had a single 97 on it and had overrich plugs and then you went with a navarro with an additional carb you purchased from the UK and still have the sam eproblem, then I'd be looking at the original carb - see what I mean?
When troubleshooting carbs I take them off the engine, raise them above the bench with 10" tall 5/16ths threaded rods (3 or 4 of them installed in the bolt holes) and then pump fuel into the carbs and see if they dribble under pressure. Fix each carb before reinstalling on the engine.
I tend to isolate, test and fix each componant away from the engine and then test/tune as an assembly after I know with certanty that each componant is working proper. If you have one carb with a dribble from powervalve, another carb with too low a float and an ignition with leaking vacuum pot you will go nuts trying to find just one thing to fix and the problem is like chaseing a ball of mercury.

Re: changing plugs every 100 miles!!
 

Remove the ballast and run the coil. Will work well with the pertronixs set up.
Still feel as if the problem is fuel.......:eek:

Re: changing plugs every 100 miles!!
 

that's a test that i never do before...so i put the old carb in my bench work ...rise it and than pump fuel inside carb?

Re: changing plugs every 100 miles!!
 

If you don't have some kind of air restriction, my bet is on your jets.
MIKE :) (mikeburch)

Re: changing plugs every 100 miles!!
 

first test with the ngk b4-l plugs....engine fire up at the first attempt and seems to run good...no time to run on the Street cause is raining....i start the engine without ballast now....coil primary is 2.5 ohms.....i'm waiting now the new jets and power valves....Tomorrow i restart the flathead just to see how the plugs color became.....

Re: changing plugs every 100 miles!!
 

Well ...today i open the old 97 and that's what i try ....the accelerator pump is damaged....and the brass float has liquid inside...that's the other parts i need to change inside the carb....
Attachment 185773

Re: changing plugs every 100 miles!!
 

Sounds like you found the problem.
Float was not shutting of the gas at the right level.

Re: changing plugs every 100 miles!!
 

Yep your float has a crack in it. Easy way to test after & if you solder it is broil ,or get it pretty hot, some water & submerge the float & watch for bubbles. Make sure you empty the fluid out first & if you get too much solder on it you will have to set the float level by guessing & adjusting . More float weight = it will set lower in the bowl & the fuel level will be too high.

Re: changing plugs every 100 miles!!
 

First that pump is savable, with some care and whill your waiting for parts, take it off the carb cover, and find a tube, bottle top, maybe a 5/8 socket and put the pump rod down inside and pull the leather up around the spring, and reshape it ,,,now soak it with "neatefoot oil" or good hand cream with lanoan?? something good for leather, it will come back to life, or good enough... I would also polish the hole the pump work's in, some one pushed it in, without running it around at the start, opening (its tapered)... you don't need a lot of pump, as to where those carbs. sit.... try it sometime when all else is work and running good ...take both pump rods off and give it a run, like at 30 or 40 put in second bring the engine up to speed, now step on it hard.it should pick up and run from the get go. untell you run out of RPM's
Now as your waiting for parts, put the top back on the carb. ( no pump) ok. run the engine up to temp. get a good clean clear piece of glass. look/watch inside the carb in question, engine running at ideal, watch for moor gas to drip in, bring the engine speed up, 800 to 1000 rpm's and look some more.... you should trace the runners in the intake ,and find the plugs blacker than the others ?? they may be cooler than the others as they are weather ?? something to think about ..... OLD.....BILL

Re: changing plugs every 100 miles!!
 

brass float and fuel pump changed.....i put 0.69 power valves and 41 jets....now the engine runs very well!!