Technical Hard Starting After Sitting

My wife asks me why I always a avoid and stay away from trailers being towed.

 

Sell one, use the other twice as much and run around moms house more often.

 

Laughter is good medicine. Ha !, look at me now. I'm acting more and more like a doctor. I better watch out or I'll be doing flow tests after all.

I'll not drive the Five Six for weeks at a time and never an issue. Mechanical fuel pump, 87 pump gas, no choke, point ignition.

 

You ain't kiddin'. The rise of dash cams and videos online at YT and the like are pretty sobering.

 

Location location location

 

Weak ignition that can't lite the fuel off properly. gets it in fits and bits until enough heat in combustion chamber to to really lite it off? Just a guess? If carb is shooting fuel into engine from gitgo then it should start and run. Sounds like it needs a little heat in the cylinder to help with ignition.

 

I'm glad you brought that up first and not me. I didn't want to change topic matter from carb's to ignition (in my case distributor). I had the same hard starting in colder weather until a distributor failer caused me to drop in a cast iron unit I had stored away. Day and night difference all around but more surprising is how it's start's cold and stay's lit.

 

I'm dealing with the same temperature because I live but maybe 10 miles from Truck64 per his location provided. The temp here is high 30's to low 50's in the morning and evening's are about low 60's to high 50's.

 

Thought of that, but Ignition is pretty good - Flamethrower coil and Pertronix, new cap, rotor, plugs and wires and 1/0 battery and starter wiring throughout. Real particular about solid grounds and good connections, it doesn't cost anything extra to do that. "Clean tight connections = Happy Electrons. Nice FAT spark at the plugs. Sorta bluish-white. I don't know how else to check the spark or what to compare it with. Anybody close got a scope? You mentioned in the jetting thread that the plug pics I posted indicated weak ignition, but never explained why you thought thst was the case. I'd be interested in learning more.

Thought the same thing as you, and figured maybe it was licked when found the old coil was leaking. Nope. My reasoning though is it's not ignition related simply because it will light off instantly if a tables**** of fuel is dropped down the carb throat.

Maybe because lean mixtures are harder to ignite, is what you are saying?

The carb was remanufactured from Vapex, California. I went through everything, and it appears to me it has the same factory venturi cluster and the rest of it. Often the remanufactured carbs are ***embled from mismatched parts.

Noticed today it is missing the gasket under the screw that secures the venturi cluster. It may be, that air is getting past and not allowing for enough fuel on the pump shots, but that seems like a bit of a stretch. I'm sure I have something in the carb box- o- junk that will fit. Just looking at the pump shots though, I think it's working close enough.

 

It's gonna get warmer.
At least that's what I keep telling myself

 

I forgot about the teas**** of fuel.
Re: weak ignition can be read on the ground strap of the spark plug, a powerful igniton will leave a sharp clear line on the metal due to the heat from the current flowing in the spark. Where that line is located is a factor of timing. For some reason the more advance in timing the further into the bend the line will be, you would think it would be more an indication of dwell. The lesser total timng will move the line closer to the gap end of the plug.

 

Ford fuel pumps had a small orifice hole between suction and discharge to allow pressure from heat sinking after running to return to the tank instead of flooding the carb. Aftermarket replacement pumps have forgotten about the running of the antiques . Blown or leaking power will dump all fuel in the bowl into the intake when you turn engine off . That would be my first part to replace , one back fire through the carb and power is on a no return lunch break ! Ford carbs are a great carb , when working correctly , simple to repair . Best way to determine leaking power valve is no change when adjusting mixture screws . Good Luck , if you were near to me we could keep that old Ford running like Henry designed it to . Six cylinder carbs , base to body screws loosen up causing a vacuum leak and super had starting issues , screws must be tighten from bottom side with carb off upside down .


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"Oh Chuck you can tell yourself anything and still be blue"

 

I've read that, though it sounds to me that the line is also ***ociated with the heat range of the plug, athough ignition problems would influence that. If anything the plugs are a bit on the hot side, (I think) at least for extended highway use. The timing is around 36 to 38 degrees total. Checked spark again, it's a nice fat white spark, with a slight blue tinge. Need to figure out how to upload video.

 

The heat range is how much combustion heat the plug removes from the engine. The threads of the plug are surrounded by the water jacket and conduct heat. A 'hot' plug is very deep looking in the end and lacks surface area to conduct the heat to the water jacket, this type of plug will leave heat in the engine. A 'cold' plug has lots of surface area right out at the end, it gathers heat and transfers it to the water jacket to remove heat from the engine. A typical use of this would be if your car ran hot in the summer you can put a 'colder' plug in it to remove th eheat; in the fall and winter you'd put a 'hot' plug to leave heat in the combustion chamber. Be aware that too cold a plug will easily foul. We use EGT sensors and I've seen a 150deg temp change going from one heat range to the next.
In brief, the heat range has nothing to do with spark or how 'hot' the ignition is.

 

why don't you put a Electric fuel pump on it & forget about
the Problem.!
I have the Same Problem on my Car when I let it sit for
a week or so, turn on the Pump wait for awhile & it Fires right
up, & I have a AFB carb NO chock amall block Chevy.
what I think it is the Gas that is Doing it

Just my 3.5 cents

Live Learn & Die
a Fool

 

The fuel pump shouldn't be the problem here, since the fuel bowl has plenty of fuel, and the accelerator pump shot works, at least 15 to 20 pumps worth anyway. In the summertime it may be an issue over an extended period but that's not really the concern.

The fuel line could even be disconnected and the engine should start and run fine till the fuel remaining is exhausted from the carb.

 

Right, I get that, but the heat range will also be indicated on the ground strap - so will ignition timing? So running lots of advance, all things being equal, will cause the plug to run hotter, and may require stepping down a heat range as I understand it.

Running lean mixtures at cruise will also tend to run hotter as well?

 

Since this a starting issue and not wanting to stay lit during that time. What is your initial timing ? To low may make for a weaker vacuum signal.

 

17° initial. Cranking vacuum is good, about solid 5" Hg.

 

Ok that's saying your bottom end (ring's) is sealing good. I'm referring to engine vacuum at idle and it's ability to pull fuel from the idle circuit.

 

It seems to be holding up pretty good over the years despite my abuse ha ha. It pulls 20" vacuum at idle but, only when the initial is cranked up pretty good. I believe the factory spec is 6° BTDC. They (shop manual) go on to say that for performance or al***ude purposes or increasing fuel economy, another 5° initial can be dialed in, for 11° initial. For substandard fuels timing can be retarded, not to exceed 2° BTDC.

Minimum acceptable vacuum is 18" - but I bet it's nowhere near that at 6° initial. See where I'm goin' with that?

 

From what you have described and from your troubleshooting. I feel it's just a lean uncombustiable mixture in the intake tract. When you pump it enough or pour in the gas you richen it to a combustible mixture. Common on old carberated vehicles.

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Sure do. Factory specs worked back then and only a base line point as far as I'm concerned.

 

Sure, but let's say I set the initial timing back to 4° or 6° BTDC initial book timing, now the vacuum falls below spec. So the rings are toast?

Haven't measured idle vacuum in a while at those timing settings but it's real low, though steady. Valve lash is good.

It exceeds 18" though, only if I dial up the advance. So is it within spec? Cold compression test, all cylinders between 130-140. 130-170 is spec for an engine at normal temperature.

 

No the rings are not toasted because I was referring to vacuum while cranking the engine over (starter only, no ignition, ****er fly's shut ), not while running. Big difference.