Are you cleaning your OM642 EGR valve as well as you think?

98Firebird

Well-known member
Hey everybody,

Slow week at the shop this week for whatever reason so I decided to investigate the sticking EGR issues a little which required a bit of a sacrifice from an old, completely seized, EGR valve. I've had this issue on a couple of EGR valves lately where even after what I thought was meticulous cleaning, the valve was still sticking. What I've found is that the soot accumulation that's visible is not what everyone should be worried about, though it is a good idea to clean everything while the EGR is out.

This first pic is the EGR housing and most of the internal components in the housing area
EGR Components.jpg

Up second is what I've found as the main culprit, soot creeping up the EGR shaft (circled in red)
EGR shaft.jpg

These last 2 pics are what I've found will clean/free up even the most stuck EGR valves. I recommend heating up the shaft housing area outlined in red (don't melt the aluminum or burn yourself) so the penetrant can have a better chance to seep in. Be sure to spray penetrant in the areas circled in yellow with the shaft housing heated up and make sure to have a rag or gloves handy because you'll need to work the EGR blades back and forth after spraying the penetrant in while the housing is still hot.
Where to heat & spray penetrant.jpgCleaning 2.jpg

I had two old EGR valves I had all but written off that were totally stuck shut and still would not work after "regular cleaning" that now work completely normally after using this method. Hopefully this helps some of you guys and I'm also curious if this extends peoples EGR cleaning intervals that clean on an "as needed" basis. I know I will for sure be adding this step to any EGR valves I clean for people in the future.
 

lindenengineering

Well-known member
Hey Firebird
We just have such a specimen on the bench which seized after we supplied it new to a hard driving Sprinter expediter who has close a minimum of 1,000,000 miles on the odometer.
We will try your "freedom" solution today ! :thumbup:
Cheers Dennis
 

jrod5150

Well-known member
Hey everybody,

Slow week at the shop this week for whatever reason so I decided to investigate the sticking EGR issues a little which required a bit of a sacrifice from an old, completely seized, EGR valve. I've had this issue on a couple of EGR valves lately where even after what I thought was meticulous cleaning, the valve was still sticking. What I've found is that the soot accumulation that's visible is not what everyone should be worried about, though it is a good idea to clean everything while the EGR is out.

This first pic is the EGR housing and most of the internal components in the housing area
View attachment 220131

Up second is what I've found as the main culprit, soot creeping up the EGR shaft (circled in red)
View attachment 220134

These last 2 pics are what I've found will clean/free up even the most stuck EGR valves. I recommend heating up the shaft housing area outlined in red (don't melt the aluminum or burn yourself) so the penetrant can have a better chance to seep in. Be sure to spray penetrant in the areas circled in yellow with the shaft housing heated up and make sure to have a rag or gloves handy because you'll need to work the EGR blades back and forth after spraying the penetrant in while the housing is still hot.
View attachment 220135View attachment 220136

I had two old EGR valves I had all but written off that were totally stuck shut and still would not work after "regular cleaning" that now work completely normally after using this method. Hopefully this helps some of you guys and I'm also curious if this extends peoples EGR cleaning intervals that clean on an "as needed" basis. I know I will for sure be adding this step to any EGR valves I clean for people in the future.
Great insider information from you as usual. Thanks for your contributions :thumbup:
 

98Firebird

Well-known member
Hey Firebird
We just have such a specimen on the bench which seized after we supplied it new to a hard driving Sprinter expediter who has close a minimum of 1,000,000 miles on the odometer.
We will try your "freedom" solution today ! :thumbup:
Cheers Dennis
Excellent! Hopefully it works long term. I unfortunately have only been able to put 20 miles or so on this test valve as I've been swapping it in and driving when people bring warranty vans in while I'm waiting on EGR cleaning approval.
 

lindenengineering

Well-known member
Well we were just going to order a new one, wait for my beard to grow like Khomeini and toss it in a packet as a core return, when the new one turns up!
But we will try this freedom solution of yours first!
Cheers Dennis
 

Happy29

2020 2500 OM642 4x2 170HR
spraying the penetrant in while the housing is still hot.
What penetrant are you using or recommending? Some use Purple Power but it's quite corrosive with aluminum. What breaks down the carbon deposits but does not harm the cast alum?
 

98Firebird

Well-known member
What penetrant are you using or recommending? Some use Purple Power but it's quite corrosive with aluminum. What breaks down the carbon deposits but does not harm the cast alum?
I have used PB blaster and Kano Kroil for this part of the procedure for freeing up a stuck valve that has already been cleaned. As far as the actual cleaning goes I have used Simple green as well as the recommended Terraclean EGR cleaner.
 

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