Any substitute for a DRB3?

geordi · **Posted:** Mon Oct 07, 2013 12:42 pm

I'm not that concerned with the hard-starting at low temps. The glow plugs can't possibly counteract the cold-soaked iron and aluminum in the engine in just a second or two, so the startup will involve a bit more effort than normal. The trick is just wait without the light for a count of 5, recycle the key back off then on once more to see if the light is just as quick... THEN start it. She will still argue with you a bit, and you will want to let it idle until the sound smooths out... And ignore the white-ish smoke while this is happening. That is just really poor cold combustion.

Any random power loss that doesn't come with a code (and goes away randomly) could also be the result of a buggy Mercedes Logo Sensor or broken wires on that plug. Especially if you don't have a GDE tune. (FYI: The tuner he has can pull codes, so there is a side benefit to getting one, beyond all the main benefits) I'm not entirely certain, but I think Keith might even be able to isolate that sensor in the programming and either kill it, or just set it's range to a fixed number, effectively isolating it out of the system. I know I had talked about that with him at one point, but then I replaced the plug and the problem went away... Or it was something else at the time. Not having a code and having an intermittent electrical glitch will drive you insane.

pwrwagn · **Joined:** Mon Jul 22, 2013 2:40 am **Posts:** 192

papaindigo wrote:

For what it's worth:
1. if the seat belt light stays on all the time even with the belt fastened and you get the annoying enhanced warning chime and the Owner's Manual enhanced warning chime doesn't do anything then my quess would be you have some combination of a driver seatbelt wiring problem and/or a BCM (at least I think the body control module handles that stuff) problem. If you are good enough with wiring diagrams you can probably trace the wire and if you are really good, I'm not, you might even be able to determine if any sort of signal is associated with the wire. Check with Sir Sam on the BCM as there may be a way with the DRB3 to determine what's going on at that end with respect to the chimes.

2. glow plug light only briefly is normal but hard starting at 20F combined with a not working CEL light worries me a bit. Have you tried pulling ECU codes? I wonder if you have a bad glow plug(s) and someone has disabled the CEL to hide that fact. OEM ceramic glow plugs are a known failure point and can shed bits of broken glow plug tip into cylinders with occasional very bad results. Fix, assuming no piston/cylinder/valve damage is replacing with metal glow plugs - either OEM 5v which requires an ECU reflash or the Italian 7v drop ins (IDParts has a good deal on the latter).

I just replaced the glow plugs as I just had a new head gasket and studs put in, as well as a timing belt, water pump, belt idler pulley and . I have the metal 7 volt plugs from Italy, so it took no changes to the controller.

I only owned it before in hot weather, so no clue on the starting previous to being changed.

I did clear the DTC's with the DRB3 a few days ago and haven't had a chance to check again, to see if there's any glow plug related DTC's.

As for the belt thing... I'm gonna try to get a new (junkyard) driver's belt buckle (the old one is sticky), and then I'll pursue it more.

papaindigo · **Posted:** Tue Oct 08, 2013 8:35 am

I don't know the mechanics of how the system determines if the belt is fastened but "sticky" might be a hint. Pop the thing off, unplug the connecting wire (at least I assume it has a plug under the carpet somewhere - may require removal of driver's seat but that's only 4 bolts and one air bag plug but best do it with battery disconnected), check continuity on the wiring to the seat belt head (should, I'd guess, have no continuity when not connected to shoulder harness but have continuity with shoulder harness plugged in), if there is no continuity with shoulder harness plugged in then the problem is in that sticky head where the belt plugs in. Try some good spray lube and plugging/unplugging and recheck continuity. If no go replace might be in order but I'd check continuity on the replacement part before purchase.

Pulling codes is a good idea as is fixing that bad CEL. Just a reminder I can send instructions on the bulb fix if you email me.

pwrwagn · **Joined:** Mon Jul 22, 2013 2:40 am **Posts:** 192

Well, I solved the "loss of power" problem, where I had to cycle the key to get it work.

I knew I had a vacuum leak somewhere, but hadn't found it yet. Anyway, it was a leaky hose connection. And, it was confirmed when I changed the filter / water separator. It's difficult to get all the air out, but after getting it running, I drove off and it got a burp of air, and it did it again. Quick key cycle and we're back on and running good. I've found my code reader, so I'll check and see if I can determine what code was set. I suspect a rail pressure problem, since the pump doesn't like air bubbles much.

I knew the air leak was getting worse because the last half of my 1900 mile trip, it began to fall flat now and then when it was being pushed hard, like a run up to 80 from an onramp, and the power would go flat before it shifted.

Not any more. It goes all the way to 4K pulling well.

geordi · **Posted:** Wed Oct 09, 2013 8:22 pm

Glad to hear that it was a simple problem and that it is fixed.

Be aware, the fuel rail doesn't hold that much actual fuel space - so it might take a good bit of idling or about 15-20 miles of driving before it purges all the air out. It will eventually smooth out though.

pwrwagn · **Joined:** Mon Jul 22, 2013 2:40 am **Posts:** 192

geordi wrote:

Glad to hear that it was a simple problem and that it is fixed.

Be aware, the fuel rail doesn't hold that much actual fuel space - so it might take a good bit of idling or about 15-20 miles of driving before it purges all the air out. It will eventually smooth out though.

The velocity through the rail is more than enough to purge it almost instantly. What won't purge fast is the filter / separator. It's on the vacuum side, is complex construction, lots of places for bubbles to hide.

However, with it fixed, it just flat out runs MUCH better and smoother.

papaindigo · **Posted:** Thu Oct 10, 2013 8:44 am

Lots of posts on the topic of air in the fuel but to more or less summarize:
1. the CRD KJ uses a "puller" fuel pump (aka the CP3) located in the engine bay. This is not "unusual" as that pump location was the most common one for decades.
2. the gasser KJ uses a "pusher" fuel pump located in the fuel tank (essentially the same assembly as the fuel level sending unit in the CRD fuel tank just with a fuel pump included), which is a more "modern" design, and unfortunately the CRD and gasser share the same fuel lines which were designed for the gasser system which is under pressure from the tank. As a result the quick disconnect fittings on the CRD line, which are designed to seal under internal presssure, can allow air into the fuel as fuel is "pulled" thru the lines.
3. the CRD 1st gen fuel filter head has an undersize fuel heating element that is prone to burning out especially when air gathers in the fuel filter head and based on my personal experience air can get in via a burned element even if the leak is so tiny that fuel does not visibly come out. In addition both the 1st and 2nd gen fuel filter heads can ingest air via a) a bad seal on the bleeder screew, b) a bad seal on the bleeder pump, c) via the fuel filter gasket if the filter is not on tight or the inner gasket of the old filter is not removed during a new filter install, or d) a bad seal on the WIF sensor at the bottom of the filter. It's not impossible for diesel to foam in the tank and air the get into the system that way but that's usually associated with running the tank to exceptionally near empty which is a bad idea for a variety of reasons and something I avoid.

Solutions:
1. 2n gen filter head or other aftermarket filter alternative is generally a good first step but it won't solve other leak sources.
2. replacing (2 I think) quick disconnect fittings back by the tank (I think access to one requires dropping the tank) with quality marine grade diesel rated fuel line.
3. adding a "in line" fuel pump which can mean installing an Airtex E7181M in tank pump or something like a Facet 40109 or single Kennedy Duramax lift pump somewhere between the tank and the fuel filter head.
Which solution or combination of solutions you pick depends on your circumstances. My problem and stoutdog's was solved by a 2n gen filter head install although I have, still on the shelf, 2 Facet pumps just in case. I suspect a pump does the "best" job of pushing any bubbles thru the system quickly.

arengant · **Posted:** Thu Oct 10, 2013 10:51 pm

pwrwagn wrote:

Well, I solved the "loss of power" problem, where I had to cycle the key to get it work.

I knew I had a vacuum leak somewhere, but hadn't found it yet. Anyway, it was a leaky hose connection. And, it was confirmed when I changed the filter / water separator. It's difficult to get all the air out, but after getting it running, I drove off and it got a burp of air, and it did it again. Quick key cycle and we're back on and running good. I've found my code reader, so I'll check and see if I can determine what code was set. I suspect a rail pressure problem, since the pump doesn't like air bubbles much.

I knew the air leak was getting worse because the last half of my 1900 mile trip, it began to fall flat now and then when it was being pushed hard, like a run up to 80 from an onramp, and the power would go flat before it shifted.

Not any more. It goes all the way to 4K pulling well.

Nice, when it happened to me it was "P0093 Fuel Leakage. Large."

pwrwagn · **Joined:** Mon Jul 22, 2013 2:40 am **Posts:** 192

papaindigo wrote:

Lots of posts on the topic of air in the fuel but to more or less summarize:
1. the CRD KJ uses a "puller" fuel pump (aka the CP3) located in the engine bay. This is not "unusual" as that pump location was the most common one for decades.
2. the gasser KJ uses a "pusher" fuel pump located in the fuel tank (essentially the same assembly as the fuel level sending unit in the CRD fuel tank just with a fuel pump included), which is a more "modern" design, and unfortunately the CRD and gasser share the same fuel lines which were designed for the gasser system which is under pressure from the tank. As a result the quick disconnect fittings on the CRD line, which are designed to seal under internal presssure, can allow air into the fuel as fuel is "pulled" thru the lines.
3. the CRD 1st gen fuel filter head has an undersize fuel heating element that is prone to burning out especially when air gathers in the fuel filter head and based on my personal experience air can get in via a burned element even if the leak is so tiny that fuel does not visibly come out. In addition both the 1st and 2nd gen fuel filter heads can ingest air via a) a bad seal on the bleeder screew, b) a bad seal on the bleeder pump, c) via the fuel filter gasket if the filter is not on tight or the inner gasket of the old filter is not removed during a new filter install, or d) a bad seal on the WIF sensor at the bottom of the filter. It's not impossible for diesel to foam in the tank and air the get into the system that way but that's usually associated with running the tank to exceptionally near empty which is a bad idea for a variety of reasons and something I avoid.

Solutions:
1. 2n gen filter head or other aftermarket filter alternative is generally a good first step but it won't solve other leak sources.
2. replacing (2 I think) quick disconnect fittings back by the tank (I think access to one requires dropping the tank) with quality marine grade diesel rated fuel line.
3. adding a "in line" fuel pump which can mean installing an Airtex E7181M in tank pump or something like a Facet 40109 or single Kennedy Duramax lift pump somewhere between the tank and the fuel filter head.
Which solution or combination of solutions you pick depends on your circumstances. My problem and stoutdog's was solved by a 2n gen filter head install although I have, still on the shelf, 2 Facet pumps just in case. I suspect a pump does the "best" job of pushing any bubbles thru the system quickly.

I'd like someone to confirm that your water separator works properly under pressure. Many years ago, when I was a diesel injection tech in an injection pump (and diesel vehicle repair) shop, we had some nice factory information on how they were designed to work either under pressure or under vacuum, and some would not work when switched to the opposite, and some would. I no longer remember the specifics in design and materials. The vast majority of water separator systems are designed to be under vacuum, not pressure, and will "leak" water into the fuel injection system if not working as designed.

Now, perhaps things have changed since then, but I am very hesitant to "fix" via means that may cause other issues.

papaindigo · **Posted:** Fri Oct 11, 2013 9:45 am

pwrwagn interesting thought to which I have no answer other than to comment that:
1. a number of members are running with some type of "in line" pump and I don't recall seeing any water problems.
2. the consensus is that if you do use an "in line" pump it needs to be a low psi one. The Facet and Kennedy run on the order of 5-7psi IIRC.

Any substitute for a DRB3?

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