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Are there any problems with the Duramax fuel pump?

Are there any problems with the Duramax fuel pump?

It can also be relatively difficult to prime the fuel system once air has been introduced into the system, such as when the fuel filter is changed. The 2001 to 2004 LB7 fuel filter housings seem to be the most prone to problems. Water pump failures for Duramax engine are somewhat common.

What causes fuel starvation in a Duramax Diesel?

Fuel Starvation and/or Air in the Fuel Lines. The Duramax diesel is susceptible to fuel starvation and getting air in the fuel lines. This can be contributed to the fuel filter housing design and the fact that the Duramax does not use a lift pump. Rather, the high pressure fuel pump (injection pump) is responsible for vacuuming fuel from the tank.

Where do you Bleed the fuel line in a car?

When you are done working on the fuel system, purge the system of air. To do this, you must know how to bleed a fuel line. Open the hood of your vehicle and locate the fuel rail. This is normally located towards the back of the engine bay, on top of the engine towards the firewall.

What is a bleeder valve on a fuel line?

Locate the Schraeder valve. This valve looks like a valve stem that you would normally find on a tire. This valve is a bleeder valve that will release pressure and purge air from the system if you loosen or remove it.

What to do if your diesel fuel line is bleeding air?

Here are the steps to take in bleeding air from a diesel fuel system: 1. Turn off fuel valve. 2. Clean outside of filter housing. 3. Install new filter element and new gaskets. A little oil on the gasket will aid a tight seal. 4. I’d suggest that you fill a spin-on filter with clean fuel before installation. 5.

When to close bleed plugs on diesel engine?

Close bleed plugs after all air is removed from the fuel tank, filters, settlement bulb, and fuel pump (only one at a time working through all bleed screws beginning closest to tank and ending at nozzles if necessary). 10. Try the engine; if it doesn’t start or runs poorly, you may have to bleed the injection

How do you fix a bleed plug in a fuel pump?

Most all equipment has a hand priming pump lever to pump fuel through the system and replace trapped air. (Check operator’s manual.) Pump several times until full flow, without air bubbles, escapes from the bleed plug holes. 8. You may need to bleed filters, fuel pump and lines to the injectors.

Are there any problems with the Commons 6.6L Duramax Diesel?

Common Problems with the 6.6L Duramax Diesel. The 6.6L Duramax has been in production since 2001 and has proved, on a large scale, to be a relatively reliable and durable platform. While various versions of the engine have surfaced over the years, all generations of the Duramax are based on the same foundation.

What’s the problem with the fuel gauge on my Silverado?

Enter your ride HERE to be a part of this months Ride of the Month Challenge! Recently my 2008 Silverado’s fuel gauge started acting funny. Let me start off by telling you what it was doing.

What kind of fuel does a Silverado Duramax use?

As for fuel I have always filled up at Sunoco with their Gold diesel. The previous owner did the same. I always run the tank to empty before refilling it. I get about 300-350kms to a tank.

Why is my Duramax diesel engine not starting?

I have seen more leaks causing no starts, loss of prime and low fuel rail pressure codes from poor fitting aftermarket fuel filters use Delco only. Remember when dealing with power loss and fuel pressure issues the duramax has no in- tank or frame mount fuel pump pushing fuel to the engine.

How much power does a Duramax Diesel have?

Power was at an all-time high coming in at 397hp and 765 pounds of torque, and in order to provide this much power while still keeping pollutants low, GM needed to be able to increase the pressure in the fuel system to levels above what the tried-and-true CP3 could safely deliver.

Where does the fuel leak go on a Duramax?

Fuel leaks on a duramax are almost always on the return side of the system, the smaller of the two fuel lines traveling down the frame rail, going to the fuel cooler and back to the tank. They can leak at the cloth covered rubber return lines at the injectors, these lines can only be replaced in sets left and right side, they are expensive.

What should the idle knock sound be on a Duramax Diesel?

The sound is often more pronounced in the interior of the truck as it’s amplified by the transmission bell housing. Idle the engine at about 600 RPM with the transmission in Park or Neutral. The engine oil temperature should be 113–185°F (45–85°C). Turn the HVAC fan and radio off. Remove the accessory drive auxiliary belt.

Why does my Duramax water pump keep overheating?

This seems to be inherent of the factory water pump design. Overheating. Overheating issues with the Duramax diesel seems to be a hit-or-miss problem; some owners experience it, while others never will. Regardless, it’s more common with the Duramax than other engines.

The sound is often more pronounced in the interior of the truck as it’s amplified by the transmission bell housing. Idle the engine at about 600 RPM with the transmission in Park or Neutral. The engine oil temperature should be 113–185°F (45–85°C). Turn the HVAC fan and radio off. Remove the accessory drive auxiliary belt.

Are there any problems with my 2003 Duramax?

Thaks for the help. injectors,water pump,headgaskets,injectors again,instrument cluster,steering shaft,pinion seal,and injectors again. I have on 03 with 66,000 on it and know problems. Friend of mine has 03 asmost same truck and know problems with 145,000 on it. Sure love mine. P:S Injectors should be warrantied to 200,000.

What kind of thumping noise does a Duramax make?

As promised here is an update on my previous post regarding the thumping/knocking noise many are experiencing with the 2020 GM Duramax.

How long can a Duramax go out of service?

This special policy covers the condition described above for a period of 7 years or 200,000 miles (320,000 km), whichever occurs first, from the date the vehicle was originally placed in service, regardless of ownership. The repairs will be made at no charge to the customer.

What happens when a Duramax engine goes down?

Not only does this mean game-over for the engine, but it results in a truck that’s down for weeks (if not months) and a huge chunk of change missing from your wallet. The failure is most common in higher horsepower engines, but can still occur in moderately modified and even stock power plants.

What kind of pump does a Duramax cp4.2 use?

Like all Duramax engines from ’01-’10, the LML was also void of a lift pump from the factory. This means that not only does the CP4.2 have to pressurize fuel as high as 29,000 psi before sending it to the rails, but it also has to pull its low pressure fuel from the tank.

What’s the RPM on a 2005 GMC Duramax?

Check out the thread “2005 6.6 max rpm 2000”, there are some suggestions there. Also search for the “ice pick trick” as it is one of the suggestions that often comes up for this problem.

When did GMC Duramax lose power under load?

In 2012 there was a P1093 code and the dealer invoice states “…low rail pressure during enrichment. Command high fuel rail pressure, pressure drops. Follow diagnostic chart, test system pressure, relief valve failed” so they replaced the FPRV.

Can a GMC Duramax run with no trailer?

Dropped the boat, let it sit a while then it ran great with no trailer. Took it back and they replaced “some fittings”. So 2 months later, I don’t fish near enough, I drove it 8 hrs to the coast and hooked up to a boat. It ran about 5 miles. Same thing , light comes on loss of power but can feather it up to 40-50 but cant push it.

What causes a Chevy 2500HD to lose power under load?

Probably P0087. Check the fuel hoses at the side of the trans– they can get kinked, weak and collapse. I’ve just experienced a very similar situation with my 2005 2500HD. After driving about 2 hours, over varying terrain, I had to stop at a light (not the first on the trip).

How often does a Duramax diesel engine leak?

Fluid leaks are important to catch early as running low on fluid can cause catastrophic damage to the transmission. If you are leaking you will notice red fluid dripping from underneath the engine bay. This issue is extremely common and can occur as frequently as every 20,000-30,000 miles.

What to do if your Duramax won’t start?

Re: Duramax won’t start! I had the same problem. The LLY is famous for developing a small crack in the fuel/water filter housing. Try priming the filter (loosen small nut, push down on primer until fuel seeps out of nut, retighten nut).

Are there any issues with the Duramax pickup?

This can produce long cranks and hard starts. Glow Plug System Issues – Nearly half of the check engine lights that come in for the Duramax pickups are for glow plugs. The glow plugs burn out over time and can be a real nuisance to remove from the aluminum heads sometimes.

Are there any problems with the Duramax diesel engine?

Overheating issues with the Duramax diesel seems to be a hit-or-miss problem; some owners experience it, while others never will. Regardless, it’s more common with the Duramax than other engines.

Are there any problems with the Duramax water pump?

This seems to be inherent of the factory water pump design. Overheating issues with the Duramax diesel seems to be a hit-or-miss problem; some owners experience it, while others never will. Regardless, it’s more common with the Duramax than other engines.

Are there any problems with the LLY Duramax?

In terms of LLY injector problems, GM had sorted out the internal failures with the 2004 ½ redesign, but the LLY Duramax would occasionally exhibit a trouble code for the injectors, but in most cases it turned out to be an issue with the injector harness rubbing through and causing a short or open in the wiring.

In terms of LLY injector problems, GM had sorted out the internal failures with the 2004 ½ redesign, but the LLY Duramax would occasionally exhibit a trouble code for the injectors, but in most cases it turned out to be an issue with the injector harness rubbing through and causing a short or open in the wiring.

What to do if your Duramax injector is not working?

To relieve this problem, the wiring harness (or affected portion of the harness) will need to be replaced/repaired. Often, you can verify the problem by wiggling the wires around the injector. If the problem goes away (even momentarily), you’ve identified the affected zone.

To relieve this problem, the wiring harness (or affected portion of the harness) will need to be replaced/repaired. Often, you can verify the problem by wiggling the wires around the injector. If the problem goes away (even momentarily), you’ve identified the affected zone.

The editors of Diesel Tech Magazine contacted InjectorsDirect.com and have received the following information put together by Daniel Lehmkuhl which can be found on InjectorsDirect.com blog. According to InjectorsDirect.com, the 2011-2016 Duramax suffers from a high pressure fuel pump issue unique to this year-range model.

What are the symptoms of a bad Duramax fuel regulator?

Common Duramax Fuel Pressure Regulator Problems 1 Black Smoke. As we’ve said before, one of the most common problems that fuel pressure regulator experience is black smoke. 2 Strong gas smell. What are some of the most common symptoms of a bad fuel pressure regulator? 3 Hesitation on the gas pedal. 4 A decrease in power acceleration. …

When does a Duramax LML / LGH CP4 pump failure?

If the body casing of the pump is cracked, as in the picture, or you find metallic debris on the fuel pressure regulator screen (pictured right) this is indicative of a pump failure. InjectorsDirect.com has put together complete repair solution for LML/LGH CP4 Pump failure using all OEM parts (pictured below.)

What causes black smoke in a Duramax engine?

The engine will increase the fuel pressure, which causes the fuel pressure regulator to produce more fuel inside than the engine needs. While it is true that black smoke could be another problem, most of the time, it is a faulty fuel pressure regulator causing the smoke.

What causes a Duramax LML engine to die?

Small aluminum bits can shave off of the internals of the pump and then get circulated through the whole fuel delivery system. The fuel rail, the injectors, fuel lines, etc. all will have metal shavings circulating throughout. Once this happens, the fuel pump will fully die, leaving your engine starving of fuel.

The editors of Diesel Tech Magazine contacted InjectorsDirect.com and have received the following information put together by Daniel Lehmkuhl which can be found on InjectorsDirect.com blog. According to InjectorsDirect.com, the 2011-2016 Duramax suffers from a high pressure fuel pump issue unique to this year-range model.

What’s the fuel pressure on a Duramax cp4.2?

To handle the additional power capabilities of the engine the fuel rail pressure was increased to 30,000psi. However, the pump actually flowed 20% less fuel than its CP3 predecessor. This makes the CP4.2 highly incapable of handling additional horsepower without the addition of a lift pump.

If the body casing of the pump is cracked, as in the picture, or you find metallic debris on the fuel pressure regulator screen (pictured right) this is indicative of a pump failure. InjectorsDirect.com has put together complete repair solution for LML/LGH CP4 Pump failure using all OEM parts (pictured below.)

How big is a LMM Duramax diesel tank?

2008-2010 GMC Sierra & Chevy Silverado HD 6.6L LMM Duramax Specs Manufactured Years: 2007.5-2010 Valvetrain: Overhead Valve (OHV) 4 Valves per cylind Engine Oil Capacity: 10 Quarts With Filter Fuel: Diesel Fuel Tank Size: Short Bed: 26 Gallons Long Bed: 34 Gallo

Why did my 2004 Duramax engine not start?

My 2004 Duramax started and then died like it was out of fuel. Now it won’t start. I have about 1/4 tank of fuel, tried priming it until the batteries died.

How can I Keep my Duramax Diesel pump healthy?

However, there are measures you can take to keep the pump happy and healthy, the first being to always buy your diesel from a high-traffic, reputable filling station that’s known to dispense good, clean fuel. Second, always change the fuel filter at or before the recommended service interval.

Are there any flaws in the Cummins Duramax?

Still, and just as we exposed the shortcomings of the almighty Cummins, the Duramax isn’t without its flaws—some of them catastrophic. For example, did you know the injection pump on the LML version is prone to coming apart and wrecking the entire high-pressure fuel system when it does?

Like all Duramax engines from ’01-’10, the LML was also void of a lift pump from the factory. This means that not only does the CP4.2 have to pressurize fuel as high as 29,000 psi before sending it to the rails, but it also has to pull its low pressure fuel from the tank.

Is the water pump on the LB7 Duramax leaking?

Water Pumps – Another issue with the LB7 Duramax is the water pump leaking. This one is fairly common and unfortunately a huge pain in the butt to change. Water will seep from the underside of the pump. Be prepared though because you will have to remove the dampner pulley to get the pump off.

Can a Duramax run without a lift pump?

If you have a stock truck with no desire to add horsepower, then sure, the engine can run fine without a lift pump for a long time. But just because it can doesn’t mean it should. If you compare the CP3 in the Duramax to the CP3 in the Cummins, the one on the Duramax has to do a lot more work.

Why does my Duramax Diesel keep cutting out?

. The Duramax diesel is susceptible to fuel starvation and getting air in the fuel lines. This can be contributed to the fuel filter housing design and the fact that the Duramax does not use a lift pump. Rather, the high pressure fuel pump (injection pump) is responsible for vacuuming fuel from the tank.

What should I do if my Duramax engine wont start?

With the engine OFF, loosen fuel filter assembly plastic bleed screw a turn or so, and depress the round priming pump on top of FF assembly until fuel squires out of vent. CAREFULLY close plastic vent nut with fingers or nutdriver. Depress pump until firm. Barely finger tight with nutdriver is all you need.

How does the fuel pump work on a Duramax?

Finally, once the pressurized fuel enters the injector, it either gets sprayed directly into the cylinder to make a big boom, or if there is extra, it flows back to the tank through the injector return to start its journey all over again.

If you have a stock truck with no desire to add horsepower, then sure, the engine can run fine without a lift pump for a long time. But just because it can doesn’t mean it should. If you compare the CP3 in the Duramax to the CP3 in the Cummins, the one on the Duramax has to do a lot more work.

Power was at an all-time high coming in at 397hp and 765 pounds of torque, and in order to provide this much power while still keeping pollutants low, GM needed to be able to increase the pressure in the fuel system to levels above what the tried-and-true CP3 could safely deliver.

Is there a problem with the glow plug on my Duramax?

Often, you can verify the problem by wiggling the wires around the injector. If the problem goes away (even momentarily), you’ve identified the affected zone. Glow plug failure was a concern on the 2006 model year LBZ and LLY Duramax models, but the problem should have been long corrected for owners of these years.

Why is my Duramax diesel engine not working?

The trucks computer keeps track of how much fuel needs to be added or subtracted from each individual cylinder to make the engine run smoothly, and this value is called the balance rate. If one cylinder is contributing too much or not as much as the rest, the cause is usually a bad injector and the cure is a replacement.

What are the most common LLY Duramax engine problems?

The 6 Most Common LLY Duramax Problems. 1 1. LLY Bent Rods. While the LLY made competitive performance numbers back in 2004, the engine is certainly not competitive to the modern day diesels. 2 2. Head Gasket Failure – LLY Duramax. 3 3. EGR Valve Failure. 4 4. Glow Plug Failue – 2006 LLY Duramax. 5 5. Overheating in Pre-2006 Models.

What’s the best way to replace a fuel pump?

If playback doesn’t begin shortly, try restarting your device. I like fixing things. all kinds of things. I do pretty much everything myself. I like making things.

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Ruth Doyle