642 ENGINE
642 ENGINE
After diagnosis I found the tips of number 3 and 4 glow plugs completely melted. After further testing it appears they were just defective and there was not too much amperage or voltage sent to them. These are rapid heating ceramic glow plugs that will pre glow an engine on a below zero morning as fast as you can turn the key to start it. Im begining to wonder how these will hold up through the years after experiencing this problem with a brand new car.
1979 450SEL 6.9 - stock
1960 220SE
111 tube chassis car/undergoing full restoration. Body work in progress. Merging with a 1996 S500 (119 engine, 722.6 trans, and both subframes)
2005 S55 AMG - stock
1999 SLK230 Kompressor - stock
2006 SLK55 AMG - stock
I recently checked in a 2009 E Class with the 642 V6 Bltc Diesel, when I pulled the vehicle in the check engine light and glow plug light were on.
After diagnosis I found the tips of number 3 and 4 glow plugs completely melted. After further testing it appears they were just defective and there was not too much amperage or voltage sent to them. These are rapid heating ceramic glow plugs that will pre glow an engine on a below zero morning as fast as you can turn the key to start it. Im begining to wonder how these will hold up through the years after experiencing this problem with a brand new car.
1979 450SEL 6.9 - stock
1960 220SE
111 tube chassis car/undergoing full restoration. Body work in progress. Merging with a 1996 S500 (119 engine, 722.6 trans, and both subframes)
2005 S55 AMG - stock
1999 SLK230 Kompressor - stock
2006 SLK55 AMG - stock
To me, the OM613/OM647 (2.7L CDI) was the last good MB diesel engine sold in the USA.
ForcedInduction
05-07-2009, 08:40 AM
#2
Probably worse than the OM606. If I were to buy a CDI, removing the glowplugs and coating them in conductive antiseize would be first priority. The 642 is a throwaway engine so there are a lot of parts not designed to be replaced independently. Example: If you damage the valvecover you have to replace the entire cylinder head, the cam bores are integrated as part of the valvecover and machined with the head. #2: If you bend one piston oil jet, you have to replace the entire engine block.
To me, the OM613/OM647 (2.7L CDI) was the last good MB diesel engine sold in the USA.
My personal favorite cdi motor is the 648, it has proven its durability in my experience and can crank out some power when you put the Kleemann chip on it.
1979 450SEL 6.9 - stock
1960 220SE
111 tube chassis car/undergoing full restoration. Body work in progress. Merging with a 1996 S500 (119 engine, 722.6 trans, and both subframes)
2005 S55 AMG - stock
1999 SLK230 Kompressor - stock
2006 SLK55 AMG - stock
You are exactly right with the replacement procedures, and thats not the only engine that is like that, all of the new gas engines are of the same design. Also one of my co-workers did break one of the valve covers on the 642 trying to remove the egr, it was about $4000 for a new head and valve cover combo. Explain that one to the boss OOOPS!!
My personal favorite cdi motor is the 648, it has proven its durability in my experience and can crank out some power when you put the Kleemann chip on it.
1979 450SEL 6.9 - stock
1960 220SE
111 tube chassis car/undergoing full restoration. Body work in progress. Merging with a 1996 S500 (119 engine, 722.6 trans, and both subframes)
2005 S55 AMG - stock
1999 SLK230 Kompressor - stock
2006 SLK55 AMG - stock
A technical bulletin came out that the ceramic plugs are no longer available and steel versions are the replacement. An ECM reflash is required to lower the voltage so it won't burn out the new steel plugs.
One quick maintenance item is to squirt penetrating oil on base of each of the glow plugs to let it soak into the threads at every oil change. This will help in removal when needed. Some car manufactures specifically states to not apply anything to the threads when installing the glow plugs.
,
Gota love Mercedes Diesels!
.
DeliveryValve
05-07-2009, 11:02 AM #4Volkswagen had installed these ceramic glow plugs in their TDIs starting in 2004 and used them for a few years. They later found a number of cars with failing glow plugs that were melted as you described or would completely break off and ruin the combustion chamber of the engine, so a new engine would have to be installed. They used either Bosch or NGK ceramic plugs. These plugs have been known not to see at least 30,000 miles of life but we've seen a number of them go over 100,000 miles. So I guess it varies.
A technical bulletin came out that the ceramic plugs are no longer available and steel versions are the replacement. An ECM reflash is required to lower the voltage so it won't burn out the new steel plugs.
One quick maintenance item is to squirt penetrating oil on base of each of the glow plugs to let it soak into the threads at every oil change. This will help in removal when needed. Some car manufactures specifically states to not apply anything to the threads when installing the glow plugs.
,
Gota love Mercedes Diesels!
.
1979 450SEL 6.9 - stock
1960 220SE
111 tube chassis car/undergoing full restoration. Body work in progress. Merging with a 1996 S500 (119 engine, 722.6 trans, and both subframes)
2005 S55 AMG - stock
1999 SLK230 Kompressor - stock
2006 SLK55 AMG - stock
Thats funny you mention the tip breaking off, because after removing them I set them down on my toolbox and one of the tips broke off right then and there.
1979 450SEL 6.9 - stock
1960 220SE
111 tube chassis car/undergoing full restoration. Body work in progress. Merging with a 1996 S500 (119 engine, 722.6 trans, and both subframes)
2005 S55 AMG - stock
1999 SLK230 Kompressor - stock
2006 SLK55 AMG - stock
The procedure is to squirt oil at the base let it soak for a few. Then unscrew the plug slightly and squirt more oil and let it soak. You can repeat the process by tightening slightly and unscrewing slightly, and squirting more oil to make sure it gets all the way through and hopefully also loosen up the built up carbon. If you hit any resistance, stop, spray, go back in, and wait. If you do not hit any resistance, keep turning out but be careful not to cock the plug at any angle other than the one it sits in in the head!!!!
This is a pain in the arse, but these plugs are very delicate and absolute care is needed to remove them or else your up sh t's creek without a paddle.
Gota love Mercedes Diesels!
.
DeliveryValve
05-07-2009, 11:54 AM #6The TDI folks have found it is very important to soak the glow plugs first in penetrating oil for a few hours before taking them out. Some have not done this and the ceramic tip would break off into the combustion chamber as they were removing them.
The procedure is to squirt oil at the base let it soak for a few. Then unscrew the plug slightly and squirt more oil and let it soak. You can repeat the process by tightening slightly and unscrewing slightly, and squirting more oil to make sure it gets all the way through and hopefully also loosen up the built up carbon. If you hit any resistance, stop, spray, go back in, and wait. If you do not hit any resistance, keep turning out but be careful not to cock the plug at any angle other than the one it sits in in the head!!!!
This is a pain in the arse, but these plugs are very delicate and absolute care is needed to remove them or else your up sh t's creek without a paddle.
Gota love Mercedes Diesels!
.
1979 450SEL 6.9 - stock
1960 220SE
111 tube chassis car/undergoing full restoration. Body work in progress. Merging with a 1996 S500 (119 engine, 722.6 trans, and both subframes)
2005 S55 AMG - stock
1999 SLK230 Kompressor - stock
2006 SLK55 AMG - stock
I will have to try that next time, I would rather take a little extra time than wreck something. Thanks for the tip.
1979 450SEL 6.9 - stock
1960 220SE
111 tube chassis car/undergoing full restoration. Body work in progress. Merging with a 1996 S500 (119 engine, 722.6 trans, and both subframes)
2005 S55 AMG - stock
1999 SLK230 Kompressor - stock
2006 SLK55 AMG - stock
I was quite worried that some incompetent VW dealership mechanic would break them while removing them. Luckily, they replaced them without a hitch. I couldn't keep the plugs, but I took a picture of them at the dealership. The service guy thought I was crazy. But they look fine.
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Gota love Mercedes Diesels!
.
DeliveryValve
08-08-2009, 01:51 PM #8FYI - Well I got a recall notice for my 2005 Passat TDI wagen with the 2.0L BHW motor this past week to replace the ceramic glow plugs with steel and reflash the ECM so it can use the new plugs. I had a feeling that this was coming so I held on the replacement instead of installing them.
I was quite worried that some incompetent VW dealership mechanic would break them while removing them. Luckily, they replaced them without a hitch. I couldn't keep the plugs, but I took a picture of them at the dealership. The service guy thought I was crazy. But they look fine.
.
Gota love Mercedes Diesels!
.
(05-07-2009, 11:26 AM)MB TECH Thats funny you mention the tip breaking off, because after removing them I set them down on my toolbox and one of the tips broke off right then and there.
Hey MB TECH, do you remember if the glow plugs were Bosch or NGK?
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Gota love Mercedes Diesels!
.
DeliveryValve
01-22-2011, 05:42 PM #9(05-07-2009, 11:26 AM)MB TECH Thats funny you mention the tip breaking off, because after removing them I set them down on my toolbox and one of the tips broke off right then and there.
Hey MB TECH, do you remember if the glow plugs were Bosch or NGK?
.
Gota love Mercedes Diesels!
.
1979 450SEL 6.9 - stock
1960 220SE
111 tube chassis car/undergoing full restoration. Body work in progress. Merging with a 1996 S500 (119 engine, 722.6 trans, and both subframes)
2005 S55 AMG - stock
1999 SLK230 Kompressor - stock
2006 SLK55 AMG - stock
I checked one this morning and saw neither a Bosch nor NGK logo on them. The MB part # is 001 159 58 01 if you google the part number it crosses over to a Bosch # so I am going to assume it is a Bosch part. Still not sure though, I will try to look into it further.
1979 450SEL 6.9 - stock
1960 220SE
111 tube chassis car/undergoing full restoration. Body work in progress. Merging with a 1996 S500 (119 engine, 722.6 trans, and both subframes)
2005 S55 AMG - stock
1999 SLK230 Kompressor - stock
2006 SLK55 AMG - stock
Gota love Mercedes Diesels!
.
DeliveryValve
02-08-2011, 09:53 AM #11Thanks it would be interesting to know what brand it was.
Gota love Mercedes Diesels!
.
![[Image: prechamber1.jpg]](http://superturbodiesel.com/images/benz/w123%20maintentance/om617%20broken%20prechamber/prechamber1.jpg)
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