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Discussion Starter · #1 ·
When I let it sit last night it wouldn't even turn over, it would just click hard, I thought something let loose, So this morning I pulled the plugs to see if it will turn over and gas leaked out of the cylinders, two of them were quite full. So I'm thinking maybe a float got stuck in my Holley 4150 750, I'm sure there are other possibility and would like some feedback. 87 Camaro, 355 SBC 10.5 compression, strong cam. Maybe 450 hp
 

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Discussion Starter · #4 ·
Yeah I am puzzled how it would continue to pull fuel, I believe you have elect fuel pump on that car, with key off, pressure should bleed off, fuel should stop.
I have both electric and mechanical, the electric only runs when I use nitrous, I have a 2 1/2 g fuel cell under the hood I have 105 in it to run with the nitrous. =================This is getting worse, I drained the oil, and it had over a quart of gas in it.
 

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It sounds like it got hydraulic locked, so big question is, (my 1st thought) how or why did your (2) 1/2 gallon under hood tanks drain into intake / heads. Once in cylinder gas slipped past ring very slowly (over night). I say your (2) 1/2 gallon tanks because, I am thinking the other tank is lower then the intake, thus tough for gas to flow up hill via gravity.
 

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Is the mechanical pump a conventional mounted cam driven pump. If so a possibility of fuel in the oil is a hole in the pump diaphragm this allows oil to leak out of the pumping chamber to where from the upper dry chamber it is pumped past the actuator into the crank case.

The other is fuel is getting in after shutdown flooding the pistons, leaking past the rings into the crank case. That’s a lot of fuel you found and would indicate that either the electric pump in the NOx system runs when you don’t know and or that fuel system leaks past the control valve.

Bogie
 

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Do you have a fuel pressure regulatior with a pressurized rail going to the carb?

If the regulatior failed it could push excessive fuel into the engine while driving and upon shutdown. Really think you would have noticed it running that rich.
 

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Discussion Starter · #9 ·
It sounds like it got hydraulic locked, so big question is, (my 1st thought) how or why did your (2) 1/2 gallon under hood tanks drain into intake / heads. Once in cylinder gas slipped past ring very slowly (over night). I say your (2) 1/2 gallon tanks because, I am thinking the other tank is lower then the intake, thus tough for gas to flow up hill via gravity.
Good Advice , I'll check in the morning and get back to you.
 

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Discussion Starter · #10 ·
Do you have a fuel pressure regulatior with a pressurized rail going to the carb?

If the regulatior failed it could push excessive fuel into the engine while driving and upon shutdown. Really think you would have noticed it running that rich.
Again Good help, It ran like crap, I- have a quickfuel fuel pressure regulator
 

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Discussion Starter · #11 ·
Is the mechanical pump a conventional mounted cam driven pump. If so a possibility of fuel in the oil is a hole in the pump diaphragm this allows oil to leak out of the pumping chamber to where from the upper dry chamber it is pumped past the actuator into the crank case.

The other is fuel is getting in after shutdown flooding the pistons, leaking past the rings into the crank case. That’s a lot of fuel you found and would indicate that either the electric pump in the NOx system runs when you don’t know and or that fuel system leaks past the control valve.

Bogie
Thanks I have to check tomorrow , I will get back to you
 

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When you say “float check valve” you’re talking about the needle and seating the carb?
So… how about the nitrous system you mentioned. It has to have a solenoid to control the nitrous and a way to add extra fuel, correct?
If the engine spun part of a revolution before trying to compress liquid then it may have had enough momentum to bend a rod, or more likely break a piston.
 

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The first sentence in the previous post should have been “needle and seat in the carb”. I’m assuming this Holley 750 has two needle assembly’s and gaskets and power valve that could cause this.
Here’s a thought, I don’t know what kind of vehicle we’re talking about. What if the regular fuel tank can NOT vent natural pressure build up and force fuel thru the pump And past one or both needle assembly’s in the carb or some part of the nitrous system.
If you have engine damage of course that needs correcting but this fuel problem needs to be diagnosed.
I have seen fuel evaporate from the bowls of a Holley and the needle stick open and cause flooding to the point spark plugs have to be pulled to clear the cylinders of fuel.
It’s difficult to diagnose a problem of any magnitude going by another persons info. All anyone can do is make suggestions of things to be aware of.
 

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Discussion Starter · #20 ·
The first sentence in the previous post should have been “needle and seat in the carb”. I’m assuming this Holley 750 has two needle assembly’s and gaskets and power valve that could cause this.
Here’s a thought, I don’t know what kind of vehicle we’re talking about. What if the regular fuel tank can NOT vent natural pressure build up and force fuel thru the pump And past one or both needle assembly’s in the carb or some part of the nitrous system.
If you have engine damage of course that needs correcting but this fuel problem needs to be diagnosed.
I have seen fuel evaporate from the bowls of a Holley and the needle stick open and cause flooding to the point spark plugs have to be pulled to clear the cylinders of fuel.
It’s difficult to diagnose a problem of any magnitude going by another persons info. All anyone can do is make suggestions of things to be aware of.
Yes, needle and seat. Your advice is totally appreciated, and I will do my best to diagnose the fuel issue, so it doesn't happen again. Right now, though, I will check the rod bearings. And work from there, I’m guessing I have a bad bearing and will have to drop the pan.
 
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