Hard start when warm

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Coastie

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So ive got a 225 slant 6. Starts real easy in the cold, and easy if i let the car sit for 30 minutes after a drive, and starts easy if i kill it at a stop light. BUT, if i go into the store and im gone for 5 minutes or so, it takes several seconds and a small prayer to get it started. Thoughts? Weather doesnt seem to effect it.

Also, my blinkers, defrost fan, and radio seem to have quit working, but my lights all work. Can yall tell me where those fuses may be? Its a 72 swinger
 
Coastie said:
...................Also, my blinkers, defrost fan, and radio seem to have quit working, but my lights all work. Can yall tell me where those fuses may be? Its a 72 swinger
Click to expand...

Start by going to MyMopar (NO!! I don't work there) and download the 72 service manual WHICH CAME FROM HERE (Thanks, ABodyJoe) and maybe also the aftermarket wiring diagrams on that site. NOTE that those diagrams are somewhat simplified, may not always show every terminal, connector, or option

READ section 8 of the service manual
 
Since you have "so much stuff" not working, most all you posted in the latter section of your post seem to be ACCessories. This is fed FROM the ignition switch TO the fuse panel ACC buss, that is the key switches that buss ON. That buss feeds individual fuses to the different ACC circuits.

There are THREE distinct circuits in the fuse panel:

1: The HOT buss which feeds things like the tail/ parking lights (always on, key or not

2: The ACCessory buss, fed from the key

3: A special circuit is the dash dimmer controlled panel lamps, "inst" on one end of the fuse panel. This is fed off the LIGHT switch TAIL circuit and feeds (orange wiring) all panel lighting
 
Hard start, bad + or ground cable.
too much initial timing.

If you have a jumper cable. Next time it gets difficult, pop hood and attach a jumper cable from batt neg post to the engine block. See if it starts easier. If it does, the cables need upgrading or check the connection/contact at the block. Nice clean surfaces on both sides is key.

If it doesn't start with the neg jumpers, attach the other jumper to the batt pos post and to the + post on starter. Start easier? You know where the issue lies... This is all predicated on whether you have ample room to get the jumper to the + starter post.
 
^^Or, pull the coil wire and see if the cranking speeds up. That will give you a clue you have too much timing advance^^
 
For hard start when hot. I'm reading fuel percolation also. At hot engine switch off todays corn based fuel boils and floods it. 30 minutes or more allows the excess fuel to completely evaporate. There are mods that help. Rework the fuel line, thickest carb base gasket you can find. SlantsixDan might chime in with more info.
About that wire from ignition switch to the hot in run portion of fuse box... Below the steering column is a white harness connector with 4 or 5 large gauge wires, red, blue, brown, yellow, black. You might find the black one failed there, melted connector, etc... It doesn't normally fail inside the fuse box which is a good thing.
 
Coastie said:
So ive got a 225 slant 6. Starts real easy in the cold, and easy if i let the car sit for 30 minutes after a drive, and starts easy if i kill it at a stop light. BUT, if i go into the store and im gone for 5 minutes or so, it takes several seconds and a small prayer to get it started. Thoughts? Weather doesnt seem to effect it.

Also, my blinkers, defrost fan, and radio seem to have quit working, but my lights all work. Can yall tell me where those fuses may be? Its a 72 swinger
Click to expand...

@Coastie "Cranks normally but hard to start when hot" or "cranks slow when hot"?
2 distinctly different issues.
 
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Can be the pickup also, they get strange sometimes when heat soaked, driving they get air to cool them stopped not so much just a thought.
 
The only way to eliminate the start problem from fuel is a return system. Fuel filter form a late 80's car or truck with a return . But you will have to run a return to the tank on a 72 use your vent line coming up to your charcoal canister . You can also T the line at the carb bit you will have to ad a return regulator and line to the tank.

I had the same problem with my duster with a electric pump I was able to shut the fuel on and off until the boiling fuel would be used up and the floats would work. That is what is happening the floats won't shut the fuel off until cool fuel comes in. Because the fuel is dead ended at the carb with no return it takes a while and the motor floods.

I then added a return with a regulator after the carb instead of ahead of it. Big difference in the car all around. The boiling fuel is not only in the carb it is in the lines also. Note the regulators for the return look exactly the same as the regulators for before the carb. You need a return regulator to do this.

I added pics of my system before and after. My return system is expensive but there are other ways to do the same thing such as a filter from the 80's as stated. Good luck it took me a while to figure out what the heck was going on on my car.

DSCN1684.jpg


Steve 107.JPG
 
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