Is this the end of my OM642?
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GL350
Is this the end of my OM642?
Looks like there is a pinhole near what I think is the #1 cylinder. On a 2014 GL350 X166 with 128K miles.
I noticed it after a coolant leak developed.
I'd appreciate any advice as to what may be wrong here. Is this holing a known issue? Is it repairable at any sensible cost?
I noticed it after a coolant leak developed.
I'd appreciate any advice as to what may be wrong here. Is this holing a known issue? Is it repairable at any sensible cost?
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From: In the Shadow of the Tetons
2013 ML350 Bluetec
Are you sure that's not just an injector leak AKA "Black Death"? Caught early enough, it's just a matter of cleanup and replace the seal under the injector. Caught late, you have a lot of coke to clean out before the injector can be removed for resealing. It looks like you caught it early. I doubt it is much more than a leaky seal.
It was a relatively common issue on the straight 6 diesel circa 2005 (648 diesel?). I didn't experience it on mine, but I did have to mess with it when I replaced the head gaskets on my '05 Duramax. It had leaked long enough to where I had to replace the valve cover - the injector leak had coked the hole about 1/2 full. It did not come apart gracefully. Fortunately, a new valve cover was less than $200.
It was a relatively common issue on the straight 6 diesel circa 2005 (648 diesel?). I didn't experience it on mine, but I did have to mess with it when I replaced the head gaskets on my '05 Duramax. It had leaked long enough to where I had to replace the valve cover - the injector leak had coked the hole about 1/2 full. It did not come apart gracefully. Fortunately, a new valve cover was less than $200.
Last edited by rapidoxidation; Jul 31, 2025 at 12:41 AM.
Thread Starter
Member
Joined: Nov 2014
Posts: 150
Likes: 32
GL350
Are you sure that's not just an injector leak AKA "Black Death"? Caught early enough, it's just a matter of cleanup and replace the seal under the injector. Caught late, you have a lot of coke to clean out before the injector can be removed for resealing. It looks like you caught it early. I doubt it is much more than a leaky seal.
It was a relatively common issue on the straight 6 diesel circa 2005 (648 diesel?). I didn't experience it on mine, but I did have to mess with it when I replaced the head gaskets on my '05 Duramax. It had leaked long enough to where I had to replace the valve cover - the injector leak had coked the hole about 1/2 full. It did not come apart gracefully. Fortunately, a new valve cover was less than $200.
It was a relatively common issue on the straight 6 diesel circa 2005 (648 diesel?). I didn't experience it on mine, but I did have to mess with it when I replaced the head gaskets on my '05 Duramax. It had leaked long enough to where I had to replace the valve cover - the injector leak had coked the hole about 1/2 full. It did not come apart gracefully. Fortunately, a new valve cover was less than $200.
It could be an injector leak, it's hard to tell with all the black stuff on there. But would an injector seal leaking cause loss of coolant? The amount of coolant that comes out when the car runs is quite a lot.
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2005 E320, 2008 E320 Bluetec
My best guess would be that you have two separate problems. Black death, and a coolant leak. You definitely have black death, and that shouldn't be related to a coolant leak. If it is, that's probably not good. Try to find the coolant leak, and plan to do an injector reseal. There are a few good videos of the procedure to cure black death on YouTube.
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GL350
I had it evaluated at an independent shop that I trust. I have a few leaking injectors and quite a foul up in the cooling system. Estimate for repairs on the cooling - half of which were parts - is over US$1200. The cost to clean and reseat the injectors was $1400, plus a risk that not all of them would be salvageable with a replacement parts cost of $600 each.
Given the truck has some other issues it's going to Copart tomorrow. I am going to look for a GLE450 or GLE580 to replace it.
Given the truck has some other issues it's going to Copart tomorrow. I am going to look for a GLE450 or GLE580 to replace it.
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From: V E G A S
1922 Ford Model T / no OBD
I sold my GLE 300D as it become too small for me and the friend bought it from me. She commute 40 miles 1way and with stiff knee, she needs taller vehicle.
Loves 600 miles range on the tank.
