Mercury 2019 - 20HP EFI - Manual start

Dave2019

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My motor has less than 10 hours on it but has been sitting for 2-3 years with old gas in it and won't start. I've put fresh gas in, drain the filter, all hoses and from the "carb" drain on the left side.

My first question is regarding the red trouble light on the front of the motor. I've read about all the codes but my question is when pulling the motor (manual start) is it normal for the red light to flash. ( The manual doesn't answer this)

Oil level is fine
 
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Dave2019

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Model 1A2020BK
Serial OR895249

I suspect it is normal to flash when cranking as I believe its suppose to be on brieftly when the motor starts... but of course I cant get it going.
 
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alldodge

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Thanks for the SN, note the first digit is a zero

I don't know about the red light, hope someone more info can assist

Looking parts up on Mercury catalog it shows a VST (vapor separation tank)
The tank is similar to a carb with a float bowl. Meaning the fuel from the filter thru the fuel pump comes into the tank and there is a float with a needle and seat to shut off fuel into it.

So if the needle and seat hang and does not allow fuel to enter into the VST tank, then there will be no fuel to the cylinders.

Have you tried starting fluid?
I say this with caution because starting fluid can break things.

It could be the motor is clogged up and is not getting any fuel.
 

Dave2019

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Thank you.

Previously I did give it a shot of spray into the "carb' and it fired.

After cranking several times - may be 12, I checked the plugs and they are dry so given the old gas issue I think somethings clogged.

Do you think it could be clogged further on by the injectors/rail or would the VST be the mostly likely location to be plugged? I had the fuel cooler below the VST apart and cleaned all that. I was hesitant to open the VST but with trepidation I will gently give it a try. I have the service procedure manual so I don't think its necessary to take it fully apart as they describe. Looking at diagrams it looks like - just to check the - fuel inlet needle and float value.

Any further thoughts. Thanks
 

alldodge

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I would first disconnect line going into VST and see if you can get any fuel to come out. If fuel comes out then go into the VST, could be the needle is stuck or it may be clogged.
 

Dave2019

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I have the VST apart. Filter was very dirty. Before I put it back together I would like to test the High Pressure motor. It has 3 wires. Pink, yellow and white. Can I test it by connecting to 12v and if so which wires are which.?
 

alldodge

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Wish I could help but I don't have the manual, hope another can advise

Might be able to figure it out by tracing wires back to relay
 

Dave2019

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If anyone else can help identify the high pressure fuel pump wires (pump is inside the VST) Thanks.

Black with white stripe
Black with yellow stripe
Black with green stripe
 
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