NewD-MaxLLY
09-26-2004, 11:15 AM
To all,
Before I start with my question(s), I want to say that this is THE BEST forum that I have seen on the Internet. For the most part, people listen, provide helpful information or will tell you where to go to get the CORRECT information. This is not so with many of the forums that has a bunch of A---s giving - in many cases – DANGEROUS information to the uninformed. With that said, here we go.
Some time around Aug. 13, 04 I started a topic with “New LLY Stumbles, Knocks and Smokes”. As of today I do not think ANYBODY has had a lasting solution to this problem other than replacement of the pickup.
Finally the question(s).
Why do we need a heater on the fuel filter during the summer or even in MOST of the US?
SALESREP made a comment on one of the posts that started to make me think.
<Quote> fuel pressurized above 20,000 psi and braised temps over 650 degrees. prolonged exposure accelelrates thermal breakdown of fuel, that creates sediments and sludge altering spray patterns and possibly plugging filters. <End Quote>
I have driven diesel pickups since 1984. NONE of them have had a fuel heater. I know that the pressures have gone up in the fuel system. Could the extra heat in an enclosed system be “Boiling off” the lighter compounds causing a more volatile fuel mix to enter the injectors and cause them to “Cook-Off” in the injector? Something similar to this is called “Flash-Back” in an Oxy-Acet. Torch and it could cause damage. The erosion to the tip could be extensive if the fuel is igniting INSIDE the injector tip.
As far as I know, this engine (LLY) has been around only since the beginning of the summer. Could the higher outside temps combined with hot fuel etc. be the problem? Am I shooting in the dark? As I recall my tank was always below 3/8, mostly 1/4 when the problem would occur. Could it be that the heat gain from this fuel being heated and re-circulated over and over be the cause of the problem? That little radiator on the fuel return can not be sufficient enough to solve the heat gain on a 100 degree day for 7 gallons of fuel.
Has anybody tried disconnecting the fuel heater?
The NA 7.3 Ford diesel I drive for work will suck air - yes I know that air is bad for diesel fuel systems - but it happens when the tank gets around 1/4 full and I am driving on less than flat ground. This causes the injectors to get a lighter than normal amount of fuel that is mixed with air. It causes the same type of knock that I get with the D-Max and it will smoke and I get the benefit of short term extra power (if you have driven a Ford 7.3 NA you know what I mean about power benefit).
I was just thinking out loud. Any answers/feed back?
Thanks in advance.
Carl
Before I start with my question(s), I want to say that this is THE BEST forum that I have seen on the Internet. For the most part, people listen, provide helpful information or will tell you where to go to get the CORRECT information. This is not so with many of the forums that has a bunch of A---s giving - in many cases – DANGEROUS information to the uninformed. With that said, here we go.
Some time around Aug. 13, 04 I started a topic with “New LLY Stumbles, Knocks and Smokes”. As of today I do not think ANYBODY has had a lasting solution to this problem other than replacement of the pickup.
Finally the question(s).
Why do we need a heater on the fuel filter during the summer or even in MOST of the US?
SALESREP made a comment on one of the posts that started to make me think.
<Quote> fuel pressurized above 20,000 psi and braised temps over 650 degrees. prolonged exposure accelelrates thermal breakdown of fuel, that creates sediments and sludge altering spray patterns and possibly plugging filters. <End Quote>
I have driven diesel pickups since 1984. NONE of them have had a fuel heater. I know that the pressures have gone up in the fuel system. Could the extra heat in an enclosed system be “Boiling off” the lighter compounds causing a more volatile fuel mix to enter the injectors and cause them to “Cook-Off” in the injector? Something similar to this is called “Flash-Back” in an Oxy-Acet. Torch and it could cause damage. The erosion to the tip could be extensive if the fuel is igniting INSIDE the injector tip.
As far as I know, this engine (LLY) has been around only since the beginning of the summer. Could the higher outside temps combined with hot fuel etc. be the problem? Am I shooting in the dark? As I recall my tank was always below 3/8, mostly 1/4 when the problem would occur. Could it be that the heat gain from this fuel being heated and re-circulated over and over be the cause of the problem? That little radiator on the fuel return can not be sufficient enough to solve the heat gain on a 100 degree day for 7 gallons of fuel.
Has anybody tried disconnecting the fuel heater?
The NA 7.3 Ford diesel I drive for work will suck air - yes I know that air is bad for diesel fuel systems - but it happens when the tank gets around 1/4 full and I am driving on less than flat ground. This causes the injectors to get a lighter than normal amount of fuel that is mixed with air. It causes the same type of knock that I get with the D-Max and it will smoke and I get the benefit of short term extra power (if you have driven a Ford 7.3 NA you know what I mean about power benefit).
I was just thinking out loud. Any answers/feed back?
Thanks in advance.
Carl