The motor wants to start. What can I do?

[mookiex4]

Good Day all.

I have a question. I installed a 283 into my 65 GMC. The motor had been on an engine stand for about 20 years in my dads garage.

It is in the truck and is getting fuel and spark. The engine is belching out some exhaust., but is is just hanging on the line of starting, it wont start. Am I missing something? I do know that the lead from the S connection on the starter solenoid is not connected to anything. The engine turns over and everything though. Is this keeping it form starting?

I hope someone can help me out.

Thanks,
Mark

[DPowers]

Is it all original? Did it start and run b4 being put away for 20 years? Timing off maybe?

[Sharps40]

Sounds like timeing/dizzy is off. Is the dizzy stabbed right at TDC and #1 to get it started/points gap right, rotated the dizzy in both directions while cranking, etc...yer close. Bet its something simple.

[mookiex4]

Everything is original and ran when it was pulled form the late 60s Chevy Truck. No changes have been made. I turn the key and it starts and sounds like it is going to run because it is firing. I release the key and it dies. I am getting the smoky exhaust I expect since it has been sitting so long. That is what is puzzling me. I have fuel and spark. IT just will not complete the process by starting after I release the key.

Could it be running too rich or lean? It was installed as a high school auto shop project and the instructor had them rebuild the carb. Maybe it needs and initial adjustment on the 2 BBL carb? To do that I am not sure what a jumping off point would be for the two air/fuel adjustment screws.

Originally Posted by DPowers

Is it all original? Did it start and run b4 being put away for 20 years? Timing off maybe?

[mookiex4]

OK. I had my son hit the key. I advanced the Dist a bit and it backfired and the starter struggled turning the engine. I Retarded the Dist and the starter turned the engine easier and it seems like it wants to run longer now. I retarded the Dist and it is much better but wont continue running. It starts but fades away and quits running. It is right there. Any further suggestions? Should I find TDC now that the Dist is closer to what it should be at and hit it with a Timing light?

[Brad54]

And old guy told me two things that have been absolutely invaluable to me over the years:
1) 95-percent of all fuel problems, are electrical.
2) An engine needs fuel, spark, timing and compression to run. If it has those things, it can't HELP but run... it doesn't have a choice.

So any time I have an engine that doesn't want to run, I think about those two simple things, and it's always lead me to the problem.

I like to run a clear fuel filter ahead of the carb on all my engines, because that tells me if it is getting fuel to the carb... if it is, I know the problem is down-stream of the filter. If the filter is empty, or half empty, I know the fuel pump is bad. A vehicle WILL run with a bad fuel pump... enough engine vacuum will pull fuel through the lines, past the bad pump. (Drove 200 miles home without a fuel pump in my Suburban a couple years ago).
If you've got spark, you might not have enough fuel coming in to keep the engine running due to a bad pump.
If you have good fuel, and good spark, you've probably got compression, then it's timing.

-Brad

[mookiex4]

I got it started but that leads me to one question. I ran a wire form the + on the Dist Coil to the + on the battery. It fired right up like it had never been stored in a garage. I did shut off the key and it kept running. I had to disconnect the coil form the battery to get it to shut off.

THat is my next question. What am I missing on the wiring? There is a wire already on the Coil and a wire coming form the S terminal on the starter coil but is not connected. Is that my missing link?

Originally Posted by Brad54

And old guy told me two things that have been absolutely invaluable to me over the years:
1) 95-percent of all fuel problems, are electrical.
2) An engine needs fuel, spark, timing and compression to run. If it has those things, it can't HELP but run... it doesn't have a choice.

So any time I have an engine that doesn't want to run, I think about those two simple things, and it's always lead me to the problem.

I like to run a clear fuel filter ahead of the carb on all my engines, because that tells me if it is getting fuel to the carb... if it is, I know the problem is down-stream of the filter. If the filter is empty, or half empty, I know the fuel pump is bad. A vehicle WILL run with a bad fuel pump... enough engine vacuum will pull fuel through the lines, past the bad pump. (Drove 200 miles home without a fuel pump in my Suburban a couple years ago).
If you've got spark, you might not have enough fuel coming in to keep the engine running due to a bad pump.
If you have good fuel, and good spark, you've probably got compression, then it's timing.

-Brad

[Brad54]

I dunno what to tell you about the wiring... other than to get a factory shop manual. I've always made a factory shop manual the second purchase after buying the vintage vehicle!

-Brad

[71swb4x4]

I believe the S terminal goes to the neutral safety switch. Do you have an auto trans or manual?

[bama63]

there should be a purple wire to the (S) start side of the starter solenoid and a yellow wire from the (R) run side of the starter solenoid to the positive side of the coil if you have the original point type distributor.

[bedfordia]

Check your ballast resistor (rectangular ceramic block on the firewall. This lowers the voltage to the points once the engine is running. this gives you a hot spark for starting but lower voltage while running so you dont burn up the points. The wire sometimes breaks in that resistor and when you let go of the starter key the power to the dist. shuts off. This same thing happened to me.

[Sharps40]

65 has a ballast resister? I've seen em on mopars but thought all the mid 60s chevys (6 and 8) had resister wires in the bundle to lower the voltage as the wire warmed up.

[bedfordia]

I don't know if 65 has it but my 63 does.

[fleetsidelarry]

Mookie. The starter CAN'T work without power to the "s" post. either from the ignition switch or, if you run a remote solenoid, via jumper from the main power post. see the wiring diagram in the earlier post. the solenoid has to have power to engage the drive

in the old points application, there should be a resistor wire that comes out of the firewall down to the starter "I" (or sometimes "R") post and a wire from that post up to the coil. Or, you could have the resistor wire (or wire with ballast resistor as mentioned. I'm not certain when they changed to a resistor wire but I think the '65 has one) from the firewall to the coil AND a wire from the "I" post. doesn't matter, the idea is to provide the coil with full voltage during starter engagement, then drop the volts during run. HEI upgrade changes all that.

always wise to do a compression check on a motor that's sat for any length of time. rings may be stuck.

P.S. FWIW, the ignition circuit testing diagram in the 1960 truck shop manual shows a ballast resistor, the same diagram in the 1963 manual shows a resistor wire

also, those are Chevrolet shop manuals, GMC could be different