Diesel problem
Diesel problem
hi I purchased a 2005 e320cdi with low compression on #5 cylinder and when I removed the cylinder head I found damage to the exhaust valve as in the picture. I’ve never seen a valve get burnt like that it looks like a piece of the glow plug has broken off and caused the damage but luckily there is no damage to the piston crown of the cylinder head
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From: V E G A S
1922 Ford Model T / no OBD
You might want to post it in diesel section.
I have burn valves like that 20+ years ago one of Fiat and one on Toyota, but have never seen MB doing that.
Piston got melted as well, so first suspect would be bad injector.
I have burn valves like that 20+ years ago one of Fiat and one on Toyota, but have never seen MB doing that.
Piston got melted as well, so first suspect would be bad injector.
Last edited by kajtek1; Mar 14, 2018 at 03:56 PM.
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From: In the Shadow of the Tetons
2013 ML350 Bluetec
No?
The piston looks like it has a divot at the 5 o'clock position, a half inch from the rim. The cutout for the valve at that position on the rim also looks compromised. It also looks like it took some damage on the inner rim left side.
Post up a pic of neighboring pistons?
The piston looks like it has a divot at the 5 o'clock position, a half inch from the rim. The cutout for the valve at that position on the rim also looks compromised. It also looks like it took some damage on the inner rim left side.
Post up a pic of neighboring pistons?
Last edited by rapidoxidation; Mar 14, 2018 at 05:22 PM.
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From: In the Shadow of the Tetons
2013 ML350 Bluetec
Looks like the cylinder head just needs to be ground for that valve seat (and make sure the head is absolutely flat. Taking a few .001's off the deck is a good idea. How many miles on the engine? Might be worth putting some new valve guides in there and have the whole head cleaned while you have it out.
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Joined: Aug 2016
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From: S. W. Washington State
2008 E320 BlueTec, 1980 300 SD
Ha, not so if it was my car!
Maybe OK if it was max 1800 rpm air cooled agricultural gasoline utility engine but sorry it's a high Rpm modern Diesel and needs a new piston in my opinion.
But you know how opinions are...
Last edited by arto_wa; Mar 15, 2018 at 01:17 PM.
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From: V E G A S
1922 Ford Model T / no OBD
You choose not to disclosure your location, so hard to judge repair economics.
I was repairing such things in old days when engines were relatively more expensive and repairs were easier to do.
Now just to get head off inline engine is whole day of work, so in US such work is not economical as you can buy whole car of this age for the money mechanic would charge.
Economics aside, that head is toasted, or at least for complete overhaul.
Assuming the cylinders walls are not scored, the engine needs at least that piston replaced and all new rings. That for starters - expect more to show up.
Lower engine bearings on MB diesels are bulletproof, but still should be checked.
I was repairing such things in old days when engines were relatively more expensive and repairs were easier to do.
Now just to get head off inline engine is whole day of work, so in US such work is not economical as you can buy whole car of this age for the money mechanic would charge.
Economics aside, that head is toasted, or at least for complete overhaul.
Assuming the cylinders walls are not scored, the engine needs at least that piston replaced and all new rings. That for starters - expect more to show up.
Lower engine bearings on MB diesels are bulletproof, but still should be checked.
Last edited by kajtek1; Mar 15, 2018 at 01:29 PM.
I am not sure if anyone else noticed the piston bowl lip at the 9-oclock position, it's very obvious that it has started to melt. I am certain that a faulty injector caused all this mess. On a more positive note, the cylinder head looks very clean and reusable considering what has happened to this engine. Depending on how much you're willing to invest, personally I would re-surface the head, give it a valve job and run the bottom end the way it is.
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Joined: Aug 2016
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From: S. W. Washington State
2008 E320 BlueTec, 1980 300 SD
I am not sure if anyone else noticed the piston bowl lip at the 9-oclock position, it's very obvious that it has started to melt. I am certain that a faulty injector caused all this mess. On a more positive note, the cylinder head looks very clean and reusable considering what has happened to this engine. Depending on how much you're willing to invest, personally I would re-surface the head, give it a valve job and run the bottom end the way it is.
Yes it is easily noticeable. Lot of metal is missing.
I’ve decided to get the valve seat cleaned up fit a new valve and gaskets and give it a try worse case scenario I’ll drop in a used engine. I only paid $1500 for the car and I do all my on repairs so it’s still worth doing the car is 1 owner and the last owner dropped a lot of cash in the car it’s got new injections,sbc unit, cam cover,battery etc
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From: V E G A S
1922 Ford Model T / no OBD
I hope you did more inspections than posted here to come to this conclusion?
Because.. ... beside burned piston bowl, I also see bur piston edge with addition of small chunks from piston missing here and there.
When those damages on top of the piston might not play big role in engine work, chances are what piston, piston rings and cylinder walls are scored by the debris. You already did big job coming to this point, so putting it all back without actual fix is not giving good prediction.
Used MB diesel engines are not easy to find in this country.
I was seeking 320 BT for 6 month before I found rebuild in UK.
Because.. ... beside burned piston bowl, I also see bur piston edge with addition of small chunks from piston missing here and there.
When those damages on top of the piston might not play big role in engine work, chances are what piston, piston rings and cylinder walls are scored by the debris. You already did big job coming to this point, so putting it all back without actual fix is not giving good prediction.
Used MB diesel engines are not easy to find in this country.
I was seeking 320 BT for 6 month before I found rebuild in UK.
I hope you did more inspections than posted here to come to this conclusion?
Because.. ... beside burned piston bowl, I also see bur piston edge with addition of small chunks from piston missing here and there.
When those damages on top of the piston might not play big role in engine work, chances are what piston, piston rings and cylinder walls are scored by the debris. You already did big job coming to this point, so putting it all back without actual fix is not giving good prediction.
Used MB diesel engines are not easy to find in this country.
I was seeking 320 BT for 6 month before I found rebuild in UK.
Because.. ... beside burned piston bowl, I also see bur piston edge with addition of small chunks from piston missing here and there.
When those damages on top of the piston might not play big role in engine work, chances are what piston, piston rings and cylinder walls are scored by the debris. You already did big job coming to this point, so putting it all back without actual fix is not giving good prediction.
Used MB diesel engines are not easy to find in this country.
I was seeking 320 BT for 6 month before I found rebuild in UK.
Senior Member


Joined: Aug 2016
Posts: 301
Likes: 29
From: S. W. Washington State
2008 E320 BlueTec, 1980 300 SD


