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Discussion Starter · #1 ·
Hello. -Troubleshooting a new No Start issue w/ the '73.. Previously it would start very instantly -as soon as key turned all the way.. even cold, faster than any old car I've ever had. -Though w/ high 1450 rpm idle until warm, then around 650 & rough due to vac leaks at injectors on cyls 5,6,7.. Last week it died while parking.. couldn't restart -heard Fpump for the 1 second when key on.. crank & crank.. no fire. Sometimes it seems to ignite just a tad when releasing the key..? Various key wiggle attempts while trying start -no luck.
12.5V at Batt, but only 3-6 sporadic/varying? Volts at coil w/ Ign on and while start attempts. New Dist Cap, Rotor, Plugs, points clean. Recent new Fuel pump + new injectors, and all rubber fuel lines new. All wire connections for coil, points, & resistors, switchgear are clean and tight. NW & AZ car not corroded -now in San Diego. I put in new correct fuel filter and ran 12V from Batt to run Fpump 10+ seconds to build pressure, no leaks. -Then found fuse 14 for Master Relay- FP was blown -replaced it w/ 16A fuse -still no start. -Then went to replace FP & FI/ECU Relays 1 & 3. (Have correct OE SR 9850 relays) I've gone through a dozen threads here on FP relays, injectors, etc.. & gather that top left relay #1 is for FP and the one below it (#3) is for Fuel Injection/ECU... my #3 relay was a Hella brand black plastic one from prior owner -I removed it but it's base wasn't attached to panel so the 4 wire plugs came out and are now loose (photo) I didn't want to put them back in holes 1-6 wrong..
**** Thus my request for help.. the 4 loose #3 relay wire/plugs are: 1 brown/G, 1 thick red, 1 black/red-stripe & 1plug w/ 2 black wires together... I saw another photo of back of relay (either #1 or #3?) w/ same wire color combo -showing #1 hole on plastic base has thick black wire, #2 hole: empty, #3 hole: thick red, #4 hole: thin black/red-stripe, #5 hole: Brown #6 empty. -Can anyone confirm that this is how I should connect my #3 relay wires? -Then hopefully the replaced relays will have solved the no-start issue, or perhaps it's an ignition switch problem.?. TBD. I saw that @cushjbc has a big PDF wire diagram I should have/use...I'd be grateful for anyone to fwd to me. -Replacing FI seals next... Thanks in advance. -Erik
Material property Tints and shades Metal Cable Wire
Material property Tints and shades Metal Cable Wire
Rectangle Metal Font Auto part Fashion accessory
 

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1973 Wiring Diagram with markup attached. The item you are discussing and have taken a pictures of is #32 in the diagram. It looks like you need a new cap for the connector. The early connectors were made of Bakelite which becomes brittle with age. Plastic ones were used later and are more durable. The cap should be one with a clip that fits in your relay rack. Those get mangled when people force them out without pushing the release tab.

I have sacks of these from the salvage yard - PM me if you can't find those parts.
 

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Discussion Starter · #3 ·
1973 Wiring Diagram with markup attached. The item you are discussing and have taken a pictures of is #32 in the diagram. It looks like you need a new cap for the connector. The early connectors were made of Bakelite which becomes brittle with age. Plastic ones were used later and are more durable. The cap should be one with a clip that fits in your relay rack. Those get mangled when people force them out without pushing the release tab.

I have sacks of these from the salvage yard - PM me if you can't find those parts.
Awesome, thanks so much for the quick reply with the diagram file.! I appreciate the help and offer. May just glue this relay cap...
Wheel Tire Car Automotive parking light Automotive side marker light

Do you have lots of old SL parts? I may seek a couple things. ( LF '73 slim bumper guard -or just the rubber cover, + grey rubber trunk mat..?) Tomorrow's goal is to get the '73 out for a drive... then onto the '72's no-start issue... ;) -Cheers
 

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EGD,

I have parts but I don't have spare bumper guards or trunk mats.
 

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Discussion Starter · #5 ·
Ok, thanks a million Chushjbc - Wow, this wiring diagram is the greatest one I've seen & tried to understand.. This makes it much easier!! and now I have more confidence in solving this relay issue, and other things on the '72.
I'll connect replaement relay and test fuel pressure after lunch, and hopefully cruise into the sunset..;)
-SL Safely -Erik
 

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Discussion Starter · #6 ·
Fixed it -the cruise to see sunset was nice -w/ a chilly fog. She runs great. Thanks again!
 
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