Chevy Duramax issue

Just an FYI for those fellow GM tow vehicles. Recently had an issue where the truck would start, then die 2 minutes later. Found air in the fuel feed system. After priming, ran fine for a while then the same symptom. Thought the problem was the plastic bleeder, replaced it with a machined one - problem reappeared. Local shop, with a reputation said the problem "may be the filter mount ($600 to replace), however no guarantee as there is no fuel pump in or near the tank. Relies on suction. Seems normal to have some air in the fuel mix. Installed a FASS filter system, which incorporates a fuel pump, and problem resolved. Further discussion indicates Ford includes a small pump at the tank. Have not verified with Dodge. No further issues, or leaks over the past few months. Local tow truck driver says he has made a small fortune due to this oversight. Just thought I would pass along. A bonus, I did notice a small increase in fuel economy.


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Have you changed the primer module that the fuel filter screws into. Mine was bad and wouldn't hold pressure

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I had a similar problem with my GMC. I taliked to a friend of mine and told him my problem as he knows more about diesel than I ever will.
The first thing he asked is if I has one of those plastic WIX fuel filters, and I did.
He informed me that there had been some issues reported of the same problem I was having.
I installed a new metal canister filter and never had the problem again.
Take it for what it's worth.

Peace
Dave

Mine had a problem last year. After pulling the RV for a while when traveling. When you shut it off it would not start until you pumped up the primer pump. Pump it up and it would start right up and run fine. It only did it about 4 times in the few months.
I took it in to my GM shop and they found the fuel filter housing was cracked. ($600) After they replaced it I've had no more problems.

There are long threads on various Chevy/GMC Duramax sites about this problem. It happens to all of us at one time or another. Generally it is caused by air leaks around the filter head. O-Rings need to be replaced and the plastic bleeder screw cracks or the O-ring needs replacing. The two rubber lines going into the head get old and need replacing. The WIF module at the bottom of the filter becomes a problem. Basically two things cause major problems in diesels, dirt and air.

You will notice in my signature that I no longer use the expensive, and ineffective GM fuel filter ($35-40). The head has been replace with a modification that allows using a much better Cat filter ($15)and I have added a lift pump. The filter gets the dirt out and the lift pump keeps a steady stream of fuel going to the filter so that if there is an air leak at some point the system is not trying to suck fuel, as is normally the process with the Duramax system but is fed by the lift pump. Normally the system sucks fuel forward from the tank which can magnify any air leak.

Rather than pay $600 for a new filter housing, add the mod which does away with that issue.

Totally agree with Lynn1130. In addition to correcting so this never happens. Having a 2 micron cat filter will ensure your duramax fuel injectors last a long time. The injectors in these duramax engines are bosch type injectors and a 2 micron fuel filter is required. Don't ask me why the truck comes from the factory with a 6 micron inadequate filter.

My mechanic said it "may" be the fuel filter housing is cracked, however they could not prove it. By putting a low pressure pump at the tank, I expected to see leaks in the housing, seals, or filters. However nothing has materialized. I have considered the Cat filter option for the future. Thanks for the clarifying info. I have monitored the Duramax forum for options mentioned, just thought I would post one here as well


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Glad you did. It is common and not only with Duramax. I love my Duramax. It runs strong and the only time it failed me, even for a short no start session, was because of a leaky GM Filter. My mechanic took it, and since we suspected it had something to do with the filter, took the wheel well cover off, fired it up and let it run in the bay next to him while he worked on another one. About 20 minutes into running, the hidden, broken O-ring opened up and fuel began running down the side of the filter. Up until that point I could not find where it was sucking air but was sure it was.

I am not pointing fingers here but do hate the mechanic who says " I think it is" and begins the shotgun approach to repair. Find it and fix it or plan on paying for all these test parts on your own dime. Luckily I have a good diesel mechanic who will not throw parts at a problem.

The filter mod is a rather cheap safety measure but I strongly recommend a lift pump for any Duramax. The CP3 (fuel suction) is a weak point. There are a number of different ones out there just be sure that what you replace it with (for those that do) is a pass through so that if it dies your CP3 keeps on working.

Thanks for the hint on 20 minutes. I will have to check that out


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Huh? 20 minutes and a $1.20 O-ring + 1/3 hr shop time at $110 an hr or $600 and a new filter head??

Lynn,

Quick Question for you - are you saying that the Nickane filter system has a pump or that you installed it and a secondary pump as well?

Kevin,
The Nicktane filter adapter is an item that screws on to the stock filter head. At the time that you install that you should probably rebuild the OEM head's O-rings because that is where many air leaks develop. There are some other things that are done at the time of install but it is not a difficult process. You then can use the Caterpillar or Donaldson 2 micron filter which cost $15-18 rather than the expensive, OEM which is not as efficient.

The lift pump is another item and there are many brands out there. I have a Kennedy on both the 04 and 14 Duramax. That is generally installed near the fuel tank and pumps, rather than sucks like the CP3 or CP4. Sucking fuel forward from where the CP's are installed, sucks air into the system at any point in between the tank and CP if there is an air leak (filter head or bleeder screw) whereas the lift pump pushes fuel forward greatly decreasing the chance of pulling air into the line.

So short answer is that they are two different items for install.

I will add here that if someone did the filter head he/she should probably do the lift pump because the 2 micron filter is likely going to increase drag for the CP trying to suck fuel forward.

cookie said:

I had a similar problem with my GMC. I taliked to a friend of mine and told him my problem as he knows more about diesel than I ever will.
The first thing he asked is if I has one of those plastic WIX fuel filters, and I did.
He informed me that there had been some issues reported of the same problem I was having.
I installed a new metal canister filter and never had the problem again.
Take it for what it's worth.

Peace
Dave

Click to expand...

Yup cookie, I too had the same issue last summer when changing my filter
Lesson learned...no more plastic filters!

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Hey Lynn, what did the lift pump set you back? Total with labor

This is the pump that I have used on both the 04 and now the 14. I think the shop charged me about $150/175 for the install and they lifted the bed in both cases to install next to the tank. Saves draining and dropping the tank for an install. If your handy it is not that difficult a job but my back won't take much of that any longer. The pump is a flow through so if it should fail for some reason you still have the CP3/4 pulling fuel and you are not dead on the road. I used the single pump. That is plenty for stock. If you are running a tune you may want the double.

http://www.kennedydiesel.com/categoryresults3.cfm?Category=3&SubCategory=157&SubCategory2=125

Thanks Lynn.