Hey guys I had a force regen done today and the tech told me my egr valve is closing at 22% at regen and it should be 0% so that's not letting the exhaust gas get to 700 which was getting to 580. My doc temp was (585), dpf temp (1039) oulet temp (1029) is that correct or something wrong the egr valve is a year old and was taken off few months ago and clean and inspected. I was told since the exhaust gas isn't getting hot enough it keeps doing frequent regens.
(07-02-2017 )Hendog83 Wrote: [ -> ]Hey guys I had a force regen done today and the tech told me my egr valve is closing at 22% at regen and it should be 0% so that's not letting the exhaust gas get to 700 which was getting to 580. My doc temp was (585), dpf temp (1039) oulet temp (1029) is that correct or something wrong the egr valve is a year old and was taken off few months ago and clean and inspected. I was told since the exhaust gas isn't getting hot enough it keeps doing frequent regens.
On a very healthy CM871 enigne (I own one), the expected exhaust temp should be 560-600 degrees during a regen cycle. The DPF inlet temp should be roughly 1,000 degrees or so and the outlet temp about the same, but usually slightly higher after the DPF has gotten cleaned. The timespan should take 40 minutes. Here is a reference video of a healthy system...
=======
So when I read your post and what you say that mechanic has said to you ---
WHAT AN IDIOT!!!--- DON'T LET HIM TOUCH YOUR TRUCK AGAIN AND HE NEEDS TO GO BACK TO TRAINING!!!!!
i.e. --- IF IT IS REGENING TOO OFTEN, THEN IT IS NOT LIKELY THE EGR VALVE. TELL HIM TO SHOVE THAT THEORY OF NOT RUNNING 700 DEGREES RIGHT UP HIS ARSSE! -- In fact, if mine were to get to 700 degrees instead of the EXPECTED 580~600ish at the DOC inlet, I would be seriously concerned.
Thanks rawze so the egr valve doesn't close to 0% doing a regen . This was a TA truck stop tech I knew that didn't seem right after reading alot on this forum so I thought I would post that to to reassure my self. The soot level was low before the regen I'm just wondering what is causing it to regen frequently , I know cummins said the filter was on its last leg when they cleaned it a few months ago, I'm going threw before buying a new filter
(07-02-2017 )Hendog83 Wrote: [ -> ]Thanks rawze so the egr valve doesn't close to 0% doing a regen . This was a TA truck stop tech I knew that didn't seem right after reading alot on this forum so I thought I would post that to to reassure my self. The soot level was low before the regen I'm just wondering what is causing it to regen frequently , I know cummins said the filter was on its last leg when they cleaned it a few months ago, I'm going threw before buying a new filter
Many things can cause frequent regen cycles including idling a lot. If your engine has a lot of miles and age on it then it could be putting oil or other contaminants into the exhaust making it clog up more, and sometimes it is worn fuel system components. There is simply no direct answer but if you keep looking, you can usually find it. If you resort to pulling off those DOC/DPF cans, then always take pictures of their faces and get some opinion as to their health. Also the DOC filtert gets weaker over time making it more dificult to regen. Sometimes it is simply old components or components that have suffered moisture or coolant intrusion in their past.
My truck has 725,000 don't burn oil the doc was replace last year the filter was new when I bought the truck so it has close to 300,000 on it . I do egr tunes once a year the only thing I haven't checked the tube going from the back pressure sensor location to the manifold to see if it's plug because I can't get it off it is seized on there and I don't want to break it
(07-02-2017 )Hendog83 Wrote: [ -> ]My truck has 725,000 don't burn oil the doc was replace last year the filter was new when I bought the truck so it has close to 300,000 on it . I do egr tunes once a year the only thing I haven't checked the tube going from the back pressure sensor location to the manifold to see if it's plug because I can't get it off it is seized on there and I don't want to break it
it is easy to check that tube for clogging without removing it. Take off the exhaust BP sensor at the thermostat housing and spray a bit of brake cleaner into the hole then crank the truck. The brake-cleaner should come shooting back out.
(07-02-2017 )Hendog83 Wrote: [ -> ]My truck has 725,000 don't burn oil the doc was replace last year the filter was new when I bought the truck so it has close to 300,000 on it . I do egr tunes once a year the only thing I haven't checked the tube going from the back pressure sensor location to the manifold to see if it's plug because I can't get it off it is seized on there and I don't want to break it
it is easy to check that tube for clogging without removing it. Take off the exhaust BP sensor at the thermostat housing and spray a bit of brake cleaner into the hole then crank the truck. The brake-cleaner should come shooting back out.