at 79k miles, original fuel filter head may be bad

Big Montana · **Posted:** Wed May 12, 2010 8:40 pm

I am on my 3rd fuel filter. I have not changed much else except my GDE tune a few weeks ago...

At startup now, my jeep seems to stutter and spurt. The RPM gauge goes from about 600 rmp at idle to 300 rmp and back. I have NEVER messed with the bleed valve or pumper other than the two times I have changed the filter. Yesterday when I tried to bleed the engine once it was turned off, I had air before fuel finally came out. When I turned it back on, it ran like a champ.

Once the engine is warm, I would never know. I have sat at lights and it is as steady as a rock. No stutter.

Does this sound about right?

notes:
Needs new thermo as the temp has sat at 154 for about 5 months
has new BRITISH RACING GREEN CAC HOSES as of 40 miles ago.
my alternator pully has red dust on it and it seems from Keith at GDE that this is a bad thing. ( I was wondering if it isn't charging enough at low rpm but the drive at heavy throttle charges it more)

warp2diesel · **Posted:** Wed May 12, 2010 9:00 pm

Have a lift pump?
Makes it easy to find fuel leaks, they are wet.
Air leaks are dry and tough to find. Figure a way to pressurize the fuel filter head and if you have a leak, it will be wet.

Big Montana · **Posted:** Wed May 12, 2010 9:09 pm

I do not have a lift pump. I have been learning about why I may need one, and the 12 page 3 year old post that just popped up is making me understand why I should do this. I guess I neet to add that to my notes. I now have 4 things to do to my ride.

kdlewis1975 · **Posted:** Wed May 12, 2010 9:54 pm

The air leak is sometimes the hose connections on the fuel tank. I installed an external lift pump and new filter head last year only to have to drop the fuel tank anyway and replace the nylon hoses/connectors. Upon attempting to prime the system, I would hear a gurgling at the fuel tank. So, once I dropped the tank, I removed the nylon hardware and slid rubber fuel line hose over the nipples and clamped them.

warp2diesel · **Posted:** Thu May 13, 2010 6:10 am

kdlewis1975 wrote:

The air leak is sometimes the hose connections on the fuel tank. I installed an external lift pump and new filter head last year only to have to drop the fuel tank anyway and replace the nylon hoses/connectors. Upon attempting to prime the system, I would hear a gurgling at the fuel tank. So, once I dropped the tank, I removed the nylon hardware and slid rubber fuel line hose over the nipples and clamped them.

X2 I keep an eye on my external pump. One way to check for air leaking in between the external pump and tank is to push on your primer, if it is firm after you install and run for a wile, you are OK, if not you have an air leak. Mine is still firm last time I checked.

BVCRD · **Posted:** Thu May 13, 2010 8:09 am

Why do people think replacing the filter head is a fix to air in the system? WHY!!!!??? :ROTFL:

stoutdog · **Posted:** Thu May 13, 2010 8:23 am

BVCRD wrote:

Why do people think replacing the filter head is a fix to air in the system? WHY!!!!??? :ROTFL:

Because if your fuel heater plug goes bad, air will leak through there... Happened to my father's CRD and the new Mopar filter head fixed the issue. Neither of us are running on lift pumps and we both have zero air in the system.

BVCRD · **Posted:** Thu May 13, 2010 10:21 am

stoutdog wrote:

BVCRD wrote:

Why do people think replacing the filter head is a fix to air in the system? WHY!!!!??? :ROTFL:

Because if your fuel heater plug goes bad, air will leak through there... Happened to my father's CRD and the new Mopar filter head fixed the issue. Neither of us are running on lift pumps and we both have zero air in the system.

But the fuel heater only "goes bad" if there is air in the system indroduced from some other leak like the fuel line connections. Don't shoot the horse before he has even ran the race and broken a leg. :juggle:

stoutdog · **Posted:** Thu May 13, 2010 11:06 am

BVCRD wrote:

stoutdog wrote:

BVCRD wrote:

Why do people think replacing the filter head is a fix to air in the system? WHY!!!!??? :ROTFL:

Because if your fuel heater plug goes bad, air will leak through there... Happened to my father's CRD and the new Mopar filter head fixed the issue. Neither of us are running on lift pumps and we both have zero air in the system.

But the fuel heater only "goes bad" if there is air in the system indroduced from some other leak like the fuel line connections. Don't shoot the horse before he has even ran the race and broken a leg. :juggle:

My understanding was that the fuel head could leak at the fuel heater connector, causing the fuel heater plug to short circuit... my father's air in fuel problems started when we unplugged the fuel heater and ended when we replaced the filter head unit. If he was having other air leaks, I think he would've noticed over the past 10k miles....

BVCRD · **Posted:** Thu May 13, 2010 11:44 am

The connection leaks because it got hot from air being in there.

onthehunt · **Posted:** Thu May 13, 2010 1:45 pm

I also would have noticed an air in fuel problem about 40k ago....if the fuel pump fixes your problem it is just compensating for your fuel leak. You don't need a fuel pump. They do make finding a fuel leak easier though.

onthehunt · **Posted:** Thu May 13, 2010 2:05 pm

Quote:

The connection leaks because it got hot from air being in there.

Since fuel flows over the heater on it's way to the filter I really doubt it. Try again.

BVCRD · **Posted:** Thu May 13, 2010 2:38 pm

onthehunt wrote:

Quote:

The connection leaks because it got hot from air being in there.

Since fuel flows over the heater on it's way to the filter I really doubt it. Try again.

Try again? Alright. The fuel flowing over the element actually COOLS the element from over heating. Air in the system will rise to the highest point. Since air will keep the fuel from reaching or totaly bathing the element, it over heats and causes a leak and or fire on the electrical connection port. Come on. We have discussed this in great length for 4 years now. Get with the program!!! :lol:

onthehunt · **Posted:** Thu May 13, 2010 2:53 pm

Exactly what program would that be? The electric fuel pump fan-boy club?? The air-trapped in filter head burns your heater out club?? I'm not a member of either. I also don't believe the theory stating 9/11 was an inside job. Just not enough facts to support it...

BVCRD · **Posted:** Thu May 13, 2010 2:55 pm

onthehunt wrote:

Exactly what program would that be? The electric fuel pump fan-boy club?? The air-trapped in filter head burns your heater out club?? I'm not a member of either. I also don't believe the theory stating 9/11 was an inside job. Just not enough facts to support it...

Sorry, I can't help your ignorance then. The heater electrical plugs on many show signs of overheating. That would be a start.

stoutdog · **Posted:** Thu May 13, 2010 3:25 pm

onthehunt wrote:

I also would have noticed an air in fuel problem about 40k ago....if the fuel pump fixes your problem it is just compensating for your fuel leak. You don't need a fuel pump. They do make finding a fuel leak easier though.

x100

I asked the guys at GDE about this a long time ago and they said essentially the same thing. The fuel pump may help you find the leak, and it may cover it up, but it's just compensating for your still-existing problem - i.e. the filter head or hoses.

In my father's case, the fuel heater plug leaked and shorted out his fuel heater. If your explanation, BVCRD, was correct, then explain how the redesigned fuel filter head has never had an issue with leaking. If replacing the fuel filter head is only "covering up the problem," as you claim, then the new head should short out as well... air would still be circulating over the unit and shorting it out. On top of that, explain why my father's - and I'm guessing onthehunt's - CRDs have zero air in the system. We can't prime any out, 10k miles into it.... We certainly had air-in-fuel issues before the swap!

With the filter head swap, the stock system is perfectly sufficient unless one of your hoses decides to leak. If that happens, the solution is to find/fix the leak, not add a pump.

BVCRD · **Posted:** Thu May 13, 2010 3:33 pm

stoutdog wrote:

onthehunt wrote:

I also would have noticed an air in fuel problem about 40k ago....if the fuel pump fixes your problem it is just compensating for your fuel leak. You don't need a fuel pump. They do make finding a fuel leak easier though.

x100

I asked the guys at GDE about this a long time ago and they said essentially the same thing. The fuel pump may help you find the leak, and it may cover it up, but it's just compensating for your still-existing problem - i.e. the filter head or hoses.

In my father's case, the fuel heater plug leaked and shorted out his fuel heater. If your explanation, BVCRD, was correct, then explain how the redesigned fuel filter head has never had an issue with leaking. If replacing the fuel filter head is only "covering up the problem," as you claim, then the new head should short out as well... air would still be circulating over the unit and shorting it out. On top of that, explain why my father's - and I'm guessing onthehunt's - CRDs have zero air in the system. We can't prime any out, 10k miles into it....

With the filter head swap, the stock system is perfectly sufficient unless one of your hoses decides to leak. If that happens, the solution is to find/fix the leak, not add a pump.

I can't comment on the new design. It may let any air enter the combustion chamber along with fuel. It may have a bigger air capacity. I do know the new designs have air in them and are not a fix. In your cases, the air might have been coming from the fuel filter area. Maybe you didn't have a good seal. Maybe you overtightened it. Who knows? Too many variables. But more than likely on the old one, it overheated first, then leaked.

ATXKJ · **Posted:** Thu May 13, 2010 6:54 pm

Actually if you compare the old/new - the old had molding problems around the heater plug - it was a bad design - the plastic/metal didn't seal well - there were gaps along the metal insert - the new one has more plastic around the heater plug (which is why it requires a new connector) and seals better no gaps.

I have the new filter head - and a lift pump - there is no air in the system.

stoutdog · **Posted:** Thu May 13, 2010 8:40 pm

What ATXKJ said... I'm not saying your scenario is impossible BVCRD, I'm saying that there are plenty of cases where leaks began at the poorly designed fuel heater plug and actually caused issues.

Big Montana · **Posted:** Thu May 13, 2010 9:32 pm

I didn't mean to cause problems. I guess I was just thinking, "hey... I have not wanted to spend a bunch of money on a filter head that is still working... now I'm pretty sure it's leaking air because it runs like crap at startup and I can pump twice before fuel comes out... Perhaps there are other CRDers with around 79k miles who have also put off the fuel filter head swap. I better let them know that we are now brothers in the 'I don't like to pay for stuff when I don't have to but now I have to club.' I hope people don't tell me I'm full of crap."

Thanks for the advice. All of you. It's pretty obvious that I have a fuel in air problem. Does the fact that the Jeep runs just fine once it is warm mean anything? Could that indicate a leak in a different area?

at 79k miles, original fuel filter head may be bad

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