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73 Merc 500 - Choke not engaging

Sctrjother

New member
Short story long, I am total novice (as of summer 2017). Bought an old pontoon with an older motor (73 blue band 500). After buying from a guy in an area I had no cell coverage, I am kicking myself for a stupid purchase. The described and actual did not line up. Low price, should have been lower. The guy redid the choke switch, Key start and kill switch to be independent switches. All wiring was not original nor similar coloring. I have since pulled and cleaned carbs, replaced all fuel lines and filter, rebuilt the distributor and cables, rebuilt starter, replaced rectifier, replaced in and outside wiring harness. The choke DID work before I did a very stupid thing (will get to it shortly). I can manually engage the choke and get engine runs great. I have tested the solenoid as well as the choke solenoid. The primary solenoid works great. The choke solenoid is not as great but I could get it to engage when direct power testing. As I said before, the wiring from the guy I purchased from was a bit unorthodox. I mistakenly reversed polarity on a couple of the wires forgetting which was + and which was -. Turns out one of the wires was only an accessory for lights. The other was a ground. Anyway, everything else works as expected. But, the choke is not engaging. I have tried 2 switches. Both are good switched. I have the Grey wire attached to the choke solenoid and outside grey wire attached to the choke switch. The other side of the switch is attached to the black as was before. Any ideas? Should i just replace the choke solenoid?
 
Ok, I am late to the party again. So, I did get a new choke. However, I found that the issue was wiring. ID10T error. Now, I am having other issues. As soon as I fixed the wiring issue, I fired up the engine and it ran like a champ. Then, I shut it down and tried to start again. Nothin. I the engine smelled quite a bit flooded. I pulled the top carb which appeared to be dripping fuel, made sure the float levers were at the correct angle.

I talked to a boat dude in the area who said they do not work on engines this old. He told me that engines that old used leaded fuel and needed 100% octane. Would this be why I cannot start the engine again?
 
Just ignore that mechanic said and do some trouble shooting.----Do you have a manual ?----Have you replaced the water pump impeller.
 
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