I have a 1976, 460 and here is my problem.

After the engine sits for a couple days it takes a lot of cranking to get it started but it normally starts. If I shut it off and start again it starts right up (why is this?). Today I cranked it intermitinley for a bit and could not get it started then it slowed down and stopped. I tried again, it cranked slowly for a few secs and then stopped again. I waited a few minutes and tried again, cranked normal for 2 secs and then slowed down and stopped. Seemed like the battery was dying but if I wait long enough it will crank normal.

Why does the engine crank fine and then slow down but with enough waiting it will run crank fine again?

And why is it hard to start after sitting a couple days?

Any help is really appreciated im working on this truck to move cross country in and live in cali so help me get out of rhode island very grateful.-Thanks

 

My guess is starter getting hot or starting to fail. The hard starting assuming the plugs, cap, rotor etc are in good condition my guess is the carb is leaking down after it sits for a few days. Also possible fuel pump not pumping or has no vacuum to pull fuel. I have seen mechanical pumps have pressure but no vacuum.

 

Thank you for the info I'm going to work on it tomorrow so I let you know how it goes.

 

Try this, let it sit for the required time to cause the problem. Remove the air cleaner lid and carefully pour a small amount of fuel (2 oz or less) down each the float bowl vent on the Holley. Use the smallest funnel you can steal from the kitchen or mcgiver something to get the fuel in the bowl vent only. As always, use caution with gasoline... Put the air cleaner lid back on and fire it up. What you describe sounds like fuel draining out of the carb (into the intake manifold and evaporating) over time. If it runs fine at all other times I would not suspect a fuel pump/filter issue, maybe just time to rebuild the carbruator. Good luck.

 

Well, edit function no workie...

Have your battery load tested, it's a free service at Sears, advance auto etc. Clean all cable connections including grounds and starter cables.

 

My truck was doing this when I had a minuscule float bowl leak.
I would have to crank it over until the pump refilled the bowl.
All I had to do was tighten the cover screws.

 

So the batteries were the culprit for the funny cranking and the oil smells strongly of gas so does this mean that the carburetor is leaking into the intake manifold and so on or could this be caused by another problem?
Thanks - Sean

 

It could be caused by a leaking fuel pump pumping fuel into the timing case.