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Getting the engine ready to start on bare chassis, 48 DeSoto


MarcDeSoto
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So I have not replaced the wiring harness on this car yet.  The body is still off.  Before I put the body back on, I want to see how the engine runs and how the transmission shifts gears.  I have already wired the spark plug cables to the distributor and plugs.  I not concerned with the generator or regulator right now.  Can I just put an alligator clip wire from the negative battery terminal to the negative side of the coil, and the positive side of the coil to ground?  My wiring diagram also shows a wire going from the positive side of the coil to the side of the distributor.  Is that for grounding purposes?  

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yes the radiator is installed.  I do have the oil pressure gauge and temperature gauge installed.  Yes the postive battery terminal is connected to ground on the side of the block.  So to ground the points, should I connect one wire from the coil + side to ground and another wire from + side of coil to the side of the distributor?  Then prime the carburetor, time the engine, and crank?  

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1 hour ago, MarcDeSoto said:

yes the radiator is installed.  I do have the oil pressure gauge and temperature gauge installed.  Yes the postive battery terminal is connected to ground on the side of the block.  So to ground the points, should I connect one wire from the coil + side to ground and another wire from + side of coil to the side of the distributor?  Then prime the carburetor, time the engine, and crank?  

 

There should only be one wire connecting the distributor to the coil. The distributor is grounded via the engine block, just connect battery + to engine ground and you are good to go.

 

Battery neg to coil neg, battery + to engine ground, coil + to distributor. That's it.

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So you are saying just the secondary high tension cable to the center of the distributor cap and that's it?  Or maybe you mean there is no need to send a second primary wire from the + side of the coil to ground.  I think what you are saying is to send two wires to the distributor, the high tension cable, and the primary wire from the + side of the coil to the side of the distributor to ground the points.  

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7 hours ago, MarcDeSoto said:

So you are saying just the secondary high tension cable to the center of the distributor cap and that's it?  Or maybe you mean there is no need to send a second primary wire from the + side of the coil to ground.  I think what you are saying is to send two wires to the distributor, the high tension cable, and the primary wire from the + side of the coil to the side of the distributor to ground the points.  

 

Yes.

 

I didn't realize the high tension wire was a part of this discussion, I thought it was a given that it went from the coil to the distributor. Also, "to ground the points" is a misnomer since the points are grounded via the mechanical attachment of the distributor to the engine block. When the points close, they connect the coil to ground. When they open an impulse is released from the coil through the high tension cable to the distributor cap and to the plugs via the rotor.

 

Yes, a gross simplification, but maybe this is helpful.....

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Duplicate those parts of the wiring diagram that you will need to test-run the engine.  I hope this helps: 

 

Low-voltage circuit: 

From the (+) battery post, heavy cable to ground, as at the engine block. 

From the (-) battery post, heavy cable to the large post of the starter solenoid.

From the starter solenoid large post to an ignition switch or substitute:

 Coil:  On-off switch for the wire to the (-) post of the coil.

 Start:  Pushbutton for the wire to the small post of the solenoid. 

From the (+) post of the coil of the distributor (at the points).  

 

High-voltage circuit:

High voltage wire (like spark plug wires), from the end of the coil to the distributor. 

Spark plug wires from the distributor to the spark plugs.  

 

Good luck, we're all counting on you. 

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Pictures always help me.  In your case since you don't have the ignition switch installed you will go directly from the battery to the coil.  To stop the engine you just need to remove the wire from the battery.  Make sure the transmission is in neutral.  

 

 

1746636601_IgnitionSystemGoBy.jpg.d9159226d0667388ca86a8facea40382.jpg

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Also since the fuel pump is dry, I will prime the carburetor by funneling gas into the air tube to fill the float chamber.  I will not pour gas down the throat of the carburetor.  Don't want to get a burned face like Jay!  Maybe that will create enough suction to draw gas from the tank to the fuel pump.   Oh and thanks for DodgeB4ya, I will change the cold tappet clearance from .014 to .010 for intake and .012 for exhaust.  

Edited by MarcDeSoto
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13 minutes ago, MarcDeSoto said:

Also since the fuel pump is dry, I will prime the carburetor by funneling gas into the air tube to fill the float chamber.  I will not pour gas down the throat of the carburetor.  Don't want to get a burned face like Jay!  Maybe that will create enough suction to draw gas from the tank to the fuel pump.   Oh and thanks for DodgeB4ya, I will change the cold tappet clearance from .014 to .010 for intake and .012 for exhaust.  

On those occasions where I had a dry fuel system I have been able to simply remove the spark plugs (to reduce the load on the starter) then crank the engine over, in 15 second spurts with a cool down between, until I saw fuel filling the sediment bowl. Then install spark plugs and attempt to start.

 

As long as there are no leaks in the plumbing and the pump is in good shape this should work. 

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5 hours ago, MarcDeSoto said:

I've been cranking the starter since summer and it's cranking good and I have oil pressure!  

There's someone I find really cool about an engine running in a bare chassis. Maybe consider videoing your first start so I can get a giggle while watching. Nothing like the first puff of smoke and roar to life.

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I'm glad I did not video it, since my old heap's initial start up was an absolute disaster! I am just getting caught back up months later thanks to the famous honeycomb rad core and repoop oil pump fiasco. Rad was re-fitted with a GM style core eliminating the tractor like MOPAR core. Cost with shipping was about 2000$ CDN. Chinese oil pump was put in appropriate trash container and the engine refitted with a prepped NOS device which cost less than the contemporary replacement. Hoping to hear that old flatty purr like she should very soon! M

Edited by Marcel Backs
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