Fuel Back flow prevention

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Rich K.
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Fuel Back flow prevention

Post by Rich K. »

To make this short and sweet, I have to double cycle my fuel pump before I start my CC or crank it for 5-10 seconds to start. I figure it has to be a failure of some kind of back flow prevention which is responsible to keep the fuel at the injectors when the engine is off.

I have a bad feeling that this part is going to be included in the fuel pump assy. I am looking for some help on this because I don't want to continue on only to find that there is an easy fix for this. Obviously, I am not going to replace the fuel pump to fix this. :!:

Thanks for any help on this!! :wave:
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HenryJ
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Re: Fuel Back flow prevention

Post by HenryJ »

The foot valve is in the fuel pump. It is also possible that you have a leaking injector. Do the fuel pump tests to determine where the problem lies.
If it ends up being the valve at the fuel pump, the pumps days are numbered.

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Rich K.
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Re: Fuel Back flow prevention

Post by Rich K. »

Yay! Thanks Brule! Though often your wisdom brings bad news it is better to know than to wonder. I will do the checks. I'll take a dying fuel pump over a leaking injector anyday.

I started using Marvelous Mystery oil. Maybe that will extend the use I'll get before I am on the side of the road with no fuel delivery from the pump. It is an elixir that will cure anything that ails you. :roflmao: In the words of Josey Wales, "How does it work on stains", as he spits tobacco on the carpet baggers blue leisure suit. :lol:
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Re: Fuel Back flow prevention

Post by killian96ss »

You should have about 60 psi engine with the engine running, and when you shut it off it should hold that pressure for several minutes. If the pressure drops rapidly after shut down you definitely have either a bad foot valve in the pump or leaking injectors. I had both fail on my CC.

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Rich K.
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Re: Fuel Back flow prevention

Post by Rich K. »

One of the new tools I own, because of my love for this truck, is a fuel pressure gauge. I have checked the pressure in the past and what I was calling a check valve and now know as a foot valve was definitely letting the pressure drop off. It wasn't too sharp of a drop, but a drop anyway. I'm just disappointed to know it is part of the fuel pump assy.

Did you have to replace your fuel pump? I can't justify replacing it just for the pressure let off. I double cycle the pump and it starts right up. 8)
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Re: Fuel Back flow prevention

Post by HenryJ »

Rich K. wrote:Did you have to replace your fuel pump? I can't justify replacing it just for the pressure let off. I double cycle the pump and it starts right up.
I did in all instances. I have been down that road many times. It is a symptom of a pump on the way out. Eventually it will stop all together. You can try some fuel treatments to see if conditions will improve, but I suspect that you would be better saving money for the inevitable.

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Re: Fuel Back flow prevention

Post by Horsehammerr »

X2 8) JUST DO IT !! :wink:
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Rich K.
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Re: Fuel Back flow prevention

Post by Rich K. »

Just do it. I can. Since I did the 2" BL I am not near as afraid of dropping the fuel tank as I was before. I am just afraid of putting the $$ toward the pump. Better that than being on the side of the trail one day, miles away from help with no cell phone signal. Sheesh! :shock:
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Re: Fuel Back flow prevention

Post by ApproachMedium »

OK So my CC has this problem. I have to double crank it almost every time I go to start it now. Is there a better fuel pump to get? The current one only has about 20-30k on it and is no more than 2 years old. I really am not looking forward to paying $360 bucks for another new sending unit/fuel pump assembly. Is it possable to get just a pump and change it? These can be had for about $60. I will be doing the labor myself most likely to save on the cost of repair.

I know I do not have a leaking injector as it was replaced a few months ago and everything going on under the hood is cleaned out/pretty new.
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Re: Fuel Back flow prevention

Post by F9K9 »

Just my .02 but, from all that we have seen on short cutting this issue results in it needing to be readdressed in a short period of time. I hope that I am wrong.
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