Hard starting after engine has warmed up

[dodgerammit]

Hello all. On my quest to make Radio flyer more reliable, I'm pretty pleased with the carb settings.

Next on my agenda is warm starts.

When cool (engine temp, not ambient air), the engine will crank normally. The starter will make a few revs before starting the engine. No lugging at all.

Once warmed and shut down, it sounds differently. Almost like a very weak battery bogging at the compression stroke. Turn the key, half of a rev from motor, bog down, fires.

The engine has started so far, but I want to go ahead and head off any issues before they arise. Should I be suspecting a weak starter? Ignition module?

Thanks everyone!

[Cheapthrills]

Mine does the same I'm not for sure but I think it's where my timing is set.

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At 6500 ft altitude

[candymancan]

Mine does this sometimes too when its been driven for awhile and hot. I suspect its heat soak in the aging starter and the starter probably needs replaced..

[ferrum]

Have you checked your electrical connections at the starer solenoid? Mine was loose causing that warm start issue even though it always started.

[tgreese]

What type of ignition are you using? Hard start when hot (sp slow cranking) is typically from too much advance when cranking. The Motorcraft module has a circuit that helps with this, retarding the spark while cranking. It's the blue/white wire that is only energized when cranking. Otherwise you can add a toggle switch that cuts power to the coil until the engine is spinning. This uses the momentum of the rotating assembly to overcome the force of the cylinders firing. Easy test - disconnect the coil wire when hot and ist should crank normally.

[dodgerammit]

What type of ignition are you using? Hard start when hot (sp slow cranking) is typically from too much advance when cranking. The Motorcraft module has a circuit that helps with this, retarding the spark while cranking. It's the blue/white wire that is only energized when cranking. Otherwise you can add a toggle switch that cuts power to the coil until the engine is spinning. This uses the momentum of the rotating assembly to overcome the force of the cylinders firing. Easy test - disconnect the coil wire when hot and ist should crank normally.

Still running the stock module right now. I'll try this test.

[dodgerammit]

Have you checked your electrical connections at the starer solenoid? Mine was loose causing that warm start issue even though it always started.

Will check this as well

[dodgerammit]

Okay. Took the Waggy out today. Verified the hard start problem. Took it back home.

Wasn't sure which coil wire to disconnect, so I unhooked the main coil-dizzy wire.

Tried the start, and the motor cranked a couple of revs freely.

Connected the coil wire back up and it cranked about 3 times and started. What I would consider a normal sounding start.

Starter solenoid connections seemed tight.

[candymancan]

My starter needs replaced or i need to put a heat sheild there.. modern vehicles have heat sheild by the starter and exhaust down pipe. To prevent heat soak of the starter.. once my starter gets super hot if i try to start the vehicle it wont even spin over "Rarely" or itll click like the battery is dead but the batter is 96% charged according to yesturday when i checked it

[prospector]

I agree with candyman, sounds like a heat soaked starter motor, really common with headers, but it can happen to any car. If ya let it go the starter may leave you stranded. Less common is a heat soaked battery, it's rare, but a battery that's hot has less cranking capacity, just like a battery that's too cold has less capacity, something to think about.

[Curly]

Dodgerammit, your problem sounds similar to what my Cherokee was doing. Occasionally, on a hot restart, the starter would barely crank the engine, this would last maybe 2 seconds tops, sounded like a weak battery. It was very intermittent. The jeep always started. New battery, cables, connections tight, etc. Anyway, in anticipation of an upcoming camping trip to a remote area, I replaced the starter because I had no idea of how old it was. My jeep has never started better!! I inspected the brushes of the old starter before turning it in for a core, they looked Ok, about half worn. Something to think about.
Curly

[dodgerammit]

Starter motor is what it sounds like to me as well. I've noticed if I let the vehicle sit for 20-30 minutes, it starts fine. But just 2-3, then back to cranking (like running errands or getting fuel), is when it does this.