Piston Slap: Grounding a Skyliner on hot restarts?
Hello, I have a ‘59 Ford Skyliner with a rebuilt engine (7000 miles and 10 years ago) and the old carb was shot. Or so we thought. So when we had the trans rebuilt, PerTronix ignition and coil, and four-wheel discs added, we also put a new Holley carb on it. I wanted an Edelbrock, but the mechanic insisted otherwise.
That was two years ago and since then it would stop running usually after an hour of driving. It had to be towed numerous times, and the mechanic said the first carb was bad and replaced it. The problem still persisted, so a second mechanic thought fuel pump and put a new one on… nope!
I hung on to the Edelbrock carb, installed an electric fuel pump, and washed out the gas tank. That seems to have cured the problem, EXCEPT when warm it cranks and cranks before firing up. Perhaps I’m impatient, but 30 seconds of cranking is too long. I’ve read and have been told that the problem is today’s gas. Not that it’s gone bad (I use Sta-Bil), but the gas in the carb turns to fumes, so the engine is basically vapor locked.
I’d love your opinion.
Thanks for your detailed query, Craig. There are many reasons why carbureted vehicles run poorly in this age of ethanol-blended fuels. But assuming it still cranks easily (i.e. not from a bad starter or battery cables), let’s narrow it down to a pair of potential problems.
Improperly-adjusted base ignition timing can cause hot-start issues. While the PerTronix conversion kits are impressive and high quality, I’ve heard of installation issues from some people; just ensure the base timing was set correctly as per instructions.
The next issue is fuel pressure. Too high and it could flood the motor, too low and it will never feed enough go-go juice. Either is possible with an electric fuel pump upgrade. Install a fuel pressure gauge (don’t cheap out; the higher quality units are more accurate at high temperatures) or get an adjustable fuel pressure regulator with a built-in gauge. Maybe a bad ground to the fuel pump gets worse when heat is added? No matter, the adjustable regulator is also great to dial-in fuel pressure. Odds are you need 5–6 psi on a stock Ford Y-block V-8.
In general, hot-start problems mean you also need to check for a clogged fuel filter, vacuum leaks, a sticky choke, and sticky needle/float in the carburetor. If cranking also becomes difficult, have the starter tested and check for bad battery cables; inspect the entire length for signs of internal corrosion (cracks, bubbles). In this case, however, I am banking one of my two initial suggestions.
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