Hard Start when hot.
 

My '58 with a 352 4bbl starts great when cold, but is often hard to start when hot. When cranking, it seems like I have a weak battery, [even though I don't]. The cranking is hesitant, and slow with pauses. If I wait a while, and even disconnect the battery while waiting, it will often start right up. Is this a ground issue, or bad starter or solenoid? Or something else? By the way, I live in Houston, with it's 100 degree summers. The temp meter is buried to the right after it's been turned off, so I know there is a lot of heat build up in the engine.

Re: Hard Start when hot.
 

A battery loses a fair amount of power capability when it's hot. If you're parked where it isn't a bad idea open the hood, even a little, to help let heat out.

Check and clean each end of all the battery and starter cables.
If even one connection is just a little dirty any effect is accentuated by the heat.
The cable end at the starter is often ignored and should be clean and tight.
The negative battery cable should probably ground to a bare spot on the head or engine block to be the most effective. Use #2 gauge battery cables if you can.

If nothing else helps you could try an extra electric radiator fan on a thermostat that keeps running & moving air under the hood after the engine is off.

.

Re: Hard Start when hot.
 

I had same problem with my 302 , some one sent me the quote right out of a bronco owners manual . After a drive when cranking hot engine mash gas petal down only 1/4 and start engine . Seems to work well for me . Before I started doing this I would think my battery was dying and it was not going to crank .

Re: Hard Start when hot.
 

Starter is on its way out.

When the engines hot it causes the already worn bushings in the starter to expand.
The worn bushings create a demand for more battery draw since the starter armature may be dragging on the pole shoes inside the starter.

Cold engine = tighter starter bushings , less battery draw and easy start.

Make sure to load test the battery to ascertain its performance level. As long as the batterys up to snuff - its starter replacement time.

Oldmics

Re: Hard Start when hot.
 

that long bushing on the drive end always went.usually thats all you need.they used to have a small thing with a gague on it you just held it on the starter cable when it was turning over and it showed the shape of your started.havent seen one in years.

Re: Hard Start when hot.
 

With my 360 I held the accelerator to the floor about 1/2 way and waited a bit. When cranked it usually fired right up with minimum cranking.

Re: Hard Start when hot.
 

While I know your system is a 12 volt, the issue you describe is common with a 6 volt system. Often can be resolved by checking that all cables (battery, starter, solenoid) are in good shape and have good contacts. This is the cheapest step to fix, and where I'd recommend you start.

Re: Hard Start when hot.
 

When engine is hot and you get it restarted do you notice any black smoke from the exhaust? Check your exhaust manifold heat riser to see that it hasn't failed in the closed position, happened to me. Caused the engine to run much warmer on the gauge. All of the exhaust going back through the intake manifold was super heating the intake manifold and upon shutting the engine off it would boil the fuel in the carburetor. Fuel would spill over into the manifold, leak down into one of the cylinders and cause a hydraulic effect, engine did not want to turn over.

Re: Hard Start when hot.
 

darrell, I still have one in my tool box. been there for years, I have a better, more expensive fluke meter these days. the old inductive meter worked well back then. I keep it around just because of it's ease of use, if I had to do some quick roadside trouble shooting.

Re: Hard Start when hot.
 

Check your timing

Re: Hard Start when hot.
 

If you don't know anything about the starter, replace it. Cheap insurance. Also the solenoid and take a good look at all the cables. Sometimes they turn green inside and its hard to see. You may have a vapor lock issue too, but make sure the starting system is good first.

Re: Hard Start when hot.
 

First make sure the ignition resistor bypass circuit is working and you are getting full battery voltage to the coil when it is cranking.

Secondly, try removing the air cleaner and leave the hood up after the engine is hot and you have shut it down, let it sit a couple of minutes and see how it starts. If it starts easier than it has been, then I'm thinking you have a "boiling" problem in the carb. When everything is buttoned up the heat can't escape

Re: Hard Start when hot.
 

There are quite a few posts like this where the original post and question asker (123finboy in this case) never appear again since the original post.

Sal

Re: Hard Start when hot.
 

you wonder if it was a waste of time.

Re: Hard Start when hot.
 

According to his profile - he stopped in here on Oct 7th.

Maybe he has not yet fixed the problem.

Would be nice to have closure on these open topics to see what the problem turned out to be.

No good deed goes unpunished.

Oldmics

Re: Hard Start when hot.
 

Just another alien abduction... happens more that you'd think...

Re: Hard Start when hot.
 

Yes, I didn't bring this up because of him being disrespectful. Maybe it is and maybe it isn't. I mentioned it because it would be nice to hear about how the problem was resolved for our education.

Sal

Re: Hard Start when hot.
 

A problem was posted early last spring and the person disappeared for about 4+ months.....
then showed up again, after a triple bypass. Ya never know....

Re: Hard Start when hot.
 

Years ago I fought this problem on an Rambler. I had a new battery cleaned all the connections, no luck. finally even though the positive cable looked good I replaced it. instant cure. turned out to be built up corrosion inside the cable that I couldn't see. Ray