willtory Report post Posted January 15, 2018 With 114,500 miles on my 2004 Itasca Meridian powered by CAT 3126E, my mechanic has informed me that #2 and #3 injectors are bad. He recommended to change all 6. Injectors are on order, scheduled to change on Tuesday. The reason for change is a shudder at high idle (around 1200 to 1400 RPM) and driving during acceleration at around 1400 RPM. I have also been informed by this mechanic to increase my oil and filter replacement to 4,500 to 5,000 miles, and use an oil additive. My question is what if anything is recommended as an oil or fuel supplement? When looking at additives on the store shelf, there seems to be numerous brands for oil and fuel. Would appreciate the opinions of the resident experts. Share this post Link to post Share on other sites
manholt Report post Posted January 15, 2018 I put KLEEN into my tank when I fill up...keeps the injectors clean and have made a difference in performance...my Lady has a 2006 DP with a 350 CAT 40 foot and scoots along faster than me! We both use it. Right now we have the white winter mix in, along with a anti gel. First for me in Central Texas! Maybe you should give about $30 bucks a try, before you spend big $$$. Put double the mix in the first time and see what happens. Oil filter and supplement along with changing oil? Your mechanic got a kid in Private school? Have you taken your coach to a CAT Dealership or Freightliner? Share this post Link to post Share on other sites
jleamont Report post Posted January 15, 2018 The link below is what I have ran in HEUI injection engines for a few years, works well with the oil side of those injectors and keeping them free of sludge. http://www.archoil.com/ar9000-friction-modifiers/ Your engine utilizes the same technology as the Powerstrokes listed. There is a video in there somewhere explaining the issues and hurdles of a HEUI system. Share this post Link to post Share on other sites
wolfe10 Report post Posted January 15, 2018 I would SURE get a "second opinion"-- preferably from a Caterpillar dealer/tech. Could be nothing more than oil in the injector electrical connection. Same symptoms and $10 in parts. Read through this whole thread (below). There are some diagnostics to identify the issue and then the "fix": http://forum.dieselrvclub.org/index.php/topic,7558.0.html Share this post Link to post Share on other sites
willtory Report post Posted January 15, 2018 Brett, the CAT tech connected his laptop to the data port and stated there were no codes. With the engine running at fast idle (1000 RPM) we could hear and feel what I referred to as a 'miss' such as with a gasoline engine mis-fire. During driving, acceleration at around 1400 RPM, I could feel a definite shudder - it was not running gear or wheel balance. The tech selectively de-energized (?) each injector and we observed the change in RPM and engine 'sound'. Each one de-energized exhibited a definite change in engine performance with the exception of 2 injectors. This WAS with a second opinion - that being another tech. I am not excited about throwing money at the problem, but am not a diesel mechanic, so at some point I need to trust the tech's troubleshooting. Your opinion please on the oil change frequency recommendation and the oil additive. Share this post Link to post Share on other sites
wolfe10 Report post Posted January 15, 2018 Unless oil analysis shows that your oil has degraded, I would stick with factory recommendation on change interval. And, oil in the injector connection can show the same symptoms. Certainly worth pulling off the valve cover and checking all of them BEFORE jumping into the big bucks. Said another way, worth a "let's see if there is oil in there, and if any hint of that, use electric cleaner and new o rings" as the first step. Share this post Link to post Share on other sites
wildebill308 Report post Posted January 15, 2018 Before spending the money on injectors I would run a tank of fuel with extra rich mix of Diesel Kleene. I would be using a good full synthetic oil like Shell Rotella T-6 5-40. I would also follow the link that Brett posted. Bill Share this post Link to post Share on other sites
obedb Report post Posted January 15, 2018 Consider what Joe Leamont suggested. He has been in the business of keeping diesel equipment running for most of his adult life. He currently works for a well known PA trucking company at an executive level. All of the advice offered is worth a try, but the additive Joe linked to would be a simple possible fix. Share this post Link to post Share on other sites
manholt Report post Posted January 15, 2018 Sure wish I had the second part about who and what the Tech was earlier! That's why it's important to get all information up front. I would go with Brett and Joe's input first...KISS Share this post Link to post Share on other sites
willtory Report post Posted January 17, 2018 What "O" Rings? Here are two photos showing the connector on the harness side and the injector. BTW, all 6 injectors replaced, 2 had a large build-up of carbon on the tip. Engine now purring like a CAT! Share this post Link to post Share on other sites
wildebill308 Report post Posted January 17, 2018 I would start using Diesel Kleen to keep the new injectors clean. Bill Share this post Link to post Share on other sites
richard5933 Report post Posted January 17, 2018 If only two of the injectors had build up on them, would it be appropriate to check to see if everything is okay in those cylinders? Logically speaking, if this was caused due to a lack of something in the fuel (additives, etc) then wouldn't the build up be present on all the injectors and not just two? Share this post Link to post Share on other sites
willtory Report post Posted January 17, 2018 I suspect the build up was caused by over fueling of those injectors. But then what do I know?!? Share this post Link to post Share on other sites
jleamont Report post Posted January 17, 2018 HEUI injectors are notorious for failures, especially if the engine is idled a lot. Share this post Link to post Share on other sites
wolfe10 Report post Posted January 17, 2018 12 hours ago, WillTory said: What "O" Rings? Here are two photos showing the connector on the harness side and the injector. BTW, all 6 injectors replaced, 2 had a large build-up of carbon on the tip. Engine now purring like a CAT! Second picture-- the small ones around the electrical connection. They can degrade and allow oil into the connection. According to a retired Caterpillar tech (in my link above) the O rings can be obtained from most box stores, but perhaps not from Caterpillar. Again, this might not be the issue, but is certainly worth checking the connections for oil before assuming the injector is bad. If oil is present, replace the O rings on all 4 cylinders. If the connections are clean and dry, THEN go to the $$$$ fix. Certainly replacing the whole injector will fix it whether it is just a bad/oil-soaked electrical connection or a bad injector. But many $$ difference to your pocket. Share this post Link to post Share on other sites
jleamont Report post Posted January 17, 2018 Will, who did the work? Are those OE CAT replacement injectors? Share this post Link to post Share on other sites
willtory Report post Posted January 17, 2018 Seems like a lot of recommendations to go to CAT for service and information. Yes, the injectors did come from CAT. No I would NOT again take ANYTHING to the local CAT dealer. My experience with them is a BIG negative. Who did the work? a QUALIFIED technician with many years experience on CAT equipment. Am I happy? Glad to see the engine running as expected. NOT happy with the service life of the injectors (114K miles) and with waiting 4 days for CAT to deliver the injectors after they charged me to overnight them. Share this post Link to post Share on other sites
obedb Report post Posted January 17, 2018 My experience with CAT franchises has been positive. The techs know what they are doing. Yes/ their labor rate is well above the rates of nearby "local shops." Bit of a chip there? Share this post Link to post Share on other sites
manholt Report post Posted January 17, 2018 Will. Depending on where the Injectors came from...AZ is nice, warm and cozy. In Texas, we are so far below freezing the last week, that flights where canceled and other flights all over the mid west and east, where also canceled...I'm still waiting on parts that was "overnighted" before Christmas and the same 4 days ago! Your lucky you got them in 4 days!!! I had an Injector go bad in a year...speak Chinese? Share this post Link to post Share on other sites
jleamont Report post Posted January 18, 2018 Wil, why I was asking where they came from...aftermarket don't come with mounting hardware, only a CAT technician would know that the hardware also needs to be replaced as those bolts are once and done. CAT comes with the bolts in the box, so that would promt the tech to replace them. I had a guy in our shop that took the shortcut, didn't replace the hardware, truck left the shop 3 days later one injector came through the valve cover all of the oil and fuel hit the turbocharger and burned that truck to the ground. Keep in mind that mess all started with someone taking a short cut. I still have the photos from that mess . Share this post Link to post Share on other sites
manholt Report post Posted January 18, 2018 Will, I wish you well and hope you have many more miles of travel and enjoyment. If you have any issues in the future come back and we will do what we can to help! Share this post Link to post Share on other sites
arvyll Report post Posted February 6, 2018 Cat 2316. Lost an injector tip at highway speed. The tip got stuck between a valve and the head. The valve retainer broke, the valve fell into they cyl. and it crushed the piston, Metal parts all thru the engine. Engine a total loss. 113,000 miles on the coach. 1,000 miles from home. My extended warranty (good sam) only paid for damaged parts. No tax, no shipping, no "required replacement parts". My cost out of pocket for a cat certified re-manufactured long block installed was $13,500. The good sam service contract paid $25,500. The repair shop recommends a full injector replacement and a valve adjustment every 100,000 miles on the CAT engines. Share this post Link to post Share on other sites
manholt Report post Posted February 6, 2018 So, your point is? Fuel injector and valve adjustment every 100K? What make, model and year coach do you have? You'll find the valve info in your CAT manual. Share this post Link to post Share on other sites
jleamont Report post Posted February 7, 2018 CAT 2316? You mean 3126? I have heard of injector tips coming off and falling into a cylinder before, happens but rare. I can't recall it destroying the engine, reused the head on one, just replaced that piston, still have that piston in the garage as a paper weight . Right next to the boat prop DW wiped out on a sand bar . No oil additive will stop that from happening. Share this post Link to post Share on other sites