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Hydrolocked and now won't start.

MysteryMeat

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Cleaned the carbs on a 2003 cb750, reassembled them and reinstalled. Bike wouldn't crank but I was confident we were getting closer. Came back the next morning to find all the fuel had leaked out through the carbs and hydrolocked the engine.
I removed the spark plugs and got the gas out but discovered it had leaked down into my oil so I drained it. Problem now is that where before I would engage the start button there would be a cranking sound. Now there is just the click of the starter relay. I had a professional check my starter relay and he says it's fine. I pulled the starter motor and bench tested it with a battery and it works fine. I can put the bike in 1st gear and drag the bike. Rear tire is able to spin so I don't think the crank is damaged.
I'm stumped. What could have happened? Starter button works. Starter relay is getting powet.
 
12.2 on the bench doesn't mean 12.2 under load. Gotta load test it. Put the multimeter on the battery and hit the starter; watch the voltage drop. Let us know what it drops to.
 
I just replaced a battery that was 16 days old 2 weeks ago. It had 12.7 volts sitting and dropped to 2 volts under load. As Brett suggested load test it. Also did you try starting it with the cylinders full of fuel?
 
I just replaced a battery that was 16 days old 2 weeks ago. It had 12.7 volts sitting and dropped to 2 volts under load. As Brett suggested load test it. Also did you try starting it with the cylinders full of fuel?
Yes, before I knew it was hydrolocked. Only heard the click of the starter relay that time and ever since.
 
The reason I ask is it's real easy to bend a connecting rod trying to crank the engine with the cylinders full of fuel. Have you tried turning it over by hand with the plugs out?
 
May have burned up the starter. Have you tried jumping the starter solenoid? If you jump it but the start doesn't spin, you either need to rebuild it or replace it.
 
The reason I ask is it's real easy to bend a connecting rod trying to crank the engine with the cylinders full of fuel. Have you tried turning it over by hand with the plugs out?
I'm not sure how to do that. I'm able to put it in gear and manually spin the back tire.
Nothing wrong with the starter. I've taken it out and bench tested it with a battery. It spins no problem.
 
If the bike is in gear and you're turning the rear tire, the engine is turning over. Have you jumped the starter solenoid?
 
Okay if the engine turns over then you are back to the starter side. As Brett mentioned have you tested the solenoid?
 
When you day "it's fine", what does that mean? The solenoid is fine?
You could have tested that by putting a screwdriver (or other metal piece) across the solenoid connections. For free!
 
When this first happened that was the first thing I did. Nothing. No start. Then I tested power in and there's no power out when the start button is pushed.
It's not my bike and the owner was insistent that the solenoid is fine and we took it to a professional motorcycle tech who tested it and said it was fine. Owner was very angry for taking it out in the first place so my options are limited. I'm fairly certain the pro lied or didn't check it correctly.
 
If jumping the solenoid is the first thing you did, and the starter bench tested fine, then I'm confused. The starter should be turning over when jumping the solenoid. Maybe you need to check the wires to the starter and the connection at the starter.
 
He should also check to make sure that the wiring between the start button and the solenoid is okay, along with the button.
 
Exactly. If the individual components test ok then the connections between them are the next order of business.
 
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