Anybody have any actual experience with EGR marbles -- the chunks of carbon that come loose from the EGR cooler / intake manifold and stick the EGR valve open? Anybody have these stop on their own after some time, or have servicing stories on this?

I've been getting these on 3 recent occasions, maybe 100 miles or so apart. The truck loses pretty much all power below 2000 rpm, smokes and stinks bad until I pull the EGR valve and dump these out. I'm trying to decide if I need to dig in and do a new EGR cooler and oil cooler. I've read the FordDoctorsDTS.com article suggesting these are caused by and coming from a leaking EGR cooler (possibly only when very hot) over time.

I'm not currently losing any coolant that I can tell, but was losing some a few months ago (during warmer weather), but also had a leaky heater valve that I replaced at the time. Not sure if the leaky valve would account for the total coolant loss (I lost over a gallon in a few weeks).

Here's the additional details:

• 2004 Excursion with just over 109K miles
• Replaced faulty EGR valve (was sticking open) about 300 miles ago
• Replaced stock turbo with new powermax turbo 300 miles ago. Old was rusty and pitted with sticking unison ring.
• I just did a total coolant flush, oil cooler back-flush, Restore and Restore+ and added new coolant filter
• Replaced thermostat during coolant flush. ECT stays pretty close to 190 degress when warmed up.
• ECT/EOT delta is mostly between 15 to 18 degrees, sometimes slightly lower or higher. Not much change after the coolant flush, but may be slightly improved.
• I've been doing pretty regular wide open throttle tests during recent test drives with the new parts above (I'm thinking this may have broken some of this stuff loose).

Here's today's marbles. They're all dry and will crumble if crushed. They are dull gray on the inside - not metallic as they kind of look here:






Thanks.

 

wow. Another thing to watch for on these engines...

Is there an end???/....

sorry, no valuable input.
good luck

 

Since you read the FDDTS article, are you asking if the article is trustworthy, or if there might be another mechanism for the marbles to form? I thought the article stated that it was fairly certain that the leaking EGR cooler was the cause. IMO it is time for an oil and EGR cooler.

 

Thanks bismic. The FDDTS article was a good article. I'm just hoping to hear some other experiences of anybody who has worked through this, and understand the severity of what was found, or if anybody has ripped the EGR cooler out due to this and not found an issue with it. And yes, in case something else might cause this too.

I don't look forward to the time and expense of this job obviously, and would like to be positive this is the issue before digging in. As you've seen, I do have some other indicators that this *might* be what's happening, but it still seems like it's not a 100% certainty here yet.

 

Good questions for sure. Hope you get some responses. To be honest, I don't recall seeing very many posts of people w/ EGR marbles, but clearly the Techs see it occasionally.

Do you have the square or the round EGR cooler?

 

It looks to be square from what I can see, with rounded edges and has the orange connector hose. It's stock as far as I know, but we got the truck with 33k miles on it.

 

The round ones do not leak very often. It makes sense that it is a square one.

 

A follow-up here... I had at least 3 more instances of the clogged EGR valve after my original post above at about 100 miles or so apart each (keep your EGR valve removal tools handy if you get to this point -- you'll be cleaning it out at roadside or calling for a tow). I also had a chance to get good ECT / EOT difference readings during one of these trips with some long flat freeway driving. We were at a pretty steady 22 to 23 degree difference.

This was finally followed by an attempted drive where there was a LOT of steam on start-up that never went away and started looking like a steam engine train when we started moving. There was also a visible coolant level drop and a smell of coolant mixed into the steam. At this point we aborted the drive, parked it and I started taking everything apart.

The EGR valve was now visibly wet with coolant and slimy with black carbon goo. The EGR cooler had lots of visible moisture in the exhaust section (inlet and outlet) and tons of crud between the EGR cooler outlet and into the intake manifold (see photos), almost blocking the manifold port (definitely where our EGR marbles were coming from before the leak got really bad).

I sent the intake manifold out to get hot-tanked ($55) and ordered a Bullet Proof Diesel EGR cooler and new stock oil cooler and replaced both. Also did new V-belt since everything was apart and checked the IPR screen.

With the new parts in everything is running great so far (about 150 miles driving on it now). The ECT/EOT difference is now not more than 8 degrees so far.

EGR Cooler Inlet wet with coolant


EGR cooler to intake manifold port


Some of the crud extracted from intake manifold EGR cooler port


New BPD EGR cooler inlet vs old stock cooler


Hot-Tanked Intake Manifold


Oil cooler cavity


New BPD EGR Cooler mounted to intake manifold


Getting it all together

 

With all the EPA garbage, it's hard to find anyone who will dunk and chemically clean aluminum, to me, it's one of the worst parts of this job. I'll search again, I need to do one later this month. And BTW, if you put a CCV can on your truck, your intake will stay squeaky clean too.

 

FYI - too much driving w/ an EGR cooler leak can increase the risk of incurring head gasket leaks. Keep an eye on the coolant level, especially after a heavy tow.

 

Yeah, I've been worried about the head gaskets too and am keeping a close eye on everything. Hopefully the leak was small/slow enough initially that its not caused damage. When it got to the steam engine phase before I tore it down, that last drive was less than two driveway miles, speed below 20mph before we stopped.

 

You also need to take a hard look at the oil cooler. Restricted coolant flow thru the oil cooler useually causes the egr cooler failuer.
You may be lucky and it was a pinhole in weld that finally got big enough to take out the egr cooler.
Actually found that to be the cause a few times. No oil cooler issues at all but egr cooler failed. Very few tho.

 

As mentioned above, replaced the oil cooler with this too: