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Old 06-20-2013, 10:50 PM   #1
UATahoe
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Tried to start up for the first time, failed......

So finally got everything buttoned up tonight and tried to fire up the new motor in my 87 R10. Wouldn't turn over. Got under the truck and saw that the starter shaft was actually hitting the fly wheel and wouldn't engage all the way. Guessing some starter shims should fix that right up.

Here is my concern though. Fuel completely flooded out of the throttle body and spilled over onto the intake. With the starter not engaging I am hoping this caused a huge excess of fuel which flowed over. I didn't have the air cleaner title need down on top either. So, any feedback from the smarter guys in this? I am hoping the starter is the crux of all of the issues but wasn't sure if it would cause the truck to flood that bad or not. It puddled up pretty good on top of the intake.
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Old 06-21-2013, 01:52 AM   #2
INSIDIOUS '86
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Re: Tried to start up for the first time, failed......

What carb are you running first of all? It shouldn't spill over like that. Usually this is a file pressure or float issue. Are you running a high volume fuel pump?
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Old 06-21-2013, 06:36 AM   #3
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Re: Tried to start up for the first time, failed......

Tbi. Using an ep381 high pressure pump
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Old 06-21-2013, 08:25 AM   #4
chebyshortbox65
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Re: Tried to start up for the first time, failed......

Pumps to hi pressure for tbi thats the pump for ls!that pump puts out 60+ psi tbi neeeds 14-15psi
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Old 06-21-2013, 08:27 AM   #5
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Re: Tried to start up for the first time, failed......

I am installing a 383 motor with a modified throttle body. I need the higher pressure. The pump is high pressure but the throttle body is supposed to regulate it down to 18 psi. I have been working with Brian at Harris Performance and this pump along with the modified throttle body are what were recommended.
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Old 06-21-2013, 08:59 AM   #6
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Re: Tried to start up for the first time, failed......

A little more info on the issue from last night. First off, when I turned the key on you could definitely hear the fuel pump in the tank kick on. Not sure if that is normal or not. I am using a true Delco ep381 pump. The starter gear that engages the flywheel actually hits the flywheel flush instead of sliding in and engaging the flywheel teeth. I will get some shims this afternoon to try and fix that problem. At first i wasnt sure why the motor wouldnt turn over and i probably tried cranking it 4 or 5 times. I also pressed the gas pedal down 3 or 4 times during one attempt thinking maybe it was getting fuel. That was before i realized the starter wasnt engaging correctly.



After i got out and checked, fuel had spilled over onto the intake manifold. I had the air cleaner on but not tightened down. Not sure if that really matters. The round paper gasket that the air cleaner sits on was completely saturated with fuel as well. I also noticed that when you would start to crank, you could audibly hear the fuel being sprayed in the throttle body. May be a pressure problem somewhere and i am getting too much pressure. I know a little while back I had read about possibly needing to replace the fuel tank selector valve. I havent done that. Still working off of the stock valve. Didnt seem to be leaking but maybe it is causing the pressure to spike?

The throttle body is supposed to be regulated to 18 psi with a specific spring that was installed.
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Old 06-21-2013, 09:06 AM   #7
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Re: Tried to start up for the first time, failed......

Sounds like the pump is continuously running. It should prime, then the oil pressure switch turns on the fuel pump relay after it sees 3-5 PSI of oil pressure. EP381 will handle an LS engine that needs a constant 58 PSI, so you have plenty of fuel flow. It shouldn't be running out like that, unless you have a stuck injector or something.
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Old 06-21-2013, 09:12 AM   #8
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Re: Tried to start up for the first time, failed......

Yeah and the injectors are supposed to be new as well. The throttle body came as a complete overhauled and upgraded unit. The injectors are actually the cop car style injectors.

Should mention too that the pump does stop making noise. Just runs for about a second or two and then goes silent. It doesnt stay running. I was just concerned that i could hear it. Sounds like it is doing what you are saying it should though. Prime and then wait for oil pressure to kick on the pumps.
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Old 06-21-2013, 12:38 PM   #9
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Re: Tried to start up for the first time, failed......

That is what it sounds like. If you can, see if you can get someone to crank it over and then you can watch the spray pattern while it is cranking/running.
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Old 06-21-2013, 12:48 PM   #10
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Re: Tried to start up for the first time, failed......

Thats the plan this afternoon. It really does sound like i have an injector stuck open. Was told it should just pulse fuel when turning the motor over. Not spray. I have had the throttle body unit since February sitting. Was told leaveing the injectors sitting that long can cause them to stick. I will get the starter issue fixed and then bump it over to see if the injector sprays continuosly. I guess now i need to figure out how to fix an injector that is stuck open. LOL
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Old 06-21-2013, 08:19 PM   #11
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Re: Tried to start up for the first time, failed......

Definitely found the problem. Wish I knew how to post up a video. Injectors are fine. Fuel is gushing out of the pressure regulator on the back of the tbi unit. Pumps run for about 2 seconds and during that time the gas is just gushing of the pressure regulator going everywhere.

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