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Discussion Starter #1
I just got home from a 125 mile trip. Noticed the engine was knocking pretty loud. Running rough as if a cylinder was missing. When revving engine, it continues to miss and blows lots of black smoke. Injectors were done in August and have less than 10,000 miles on them. Valve lash was also set then.
Any ideas as to where to look for the problem. I am wondering if one of the valves could be out of adjustment or what...
 

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Discussion Starter #2
water n fuel?
 

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So that was the damndest thing.. I went out there to take a troubleshooting video.. started her up..same knocking and running rough.. then I revved up the engine, and when it came back to idle, she was running smooth again.. I wonder if I ran something through an injector... I'm uploading the videos now..
 

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Here is what it looked and sounded like when it was rough..
 

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Discussion Starter #5 (Edited)
Then after I revved it up again, it was back to normal
 

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iflybeach- How is your truck running now? Does it run smooth or do you get an occassional knock? I just got back towing my travel trailer approximately 300 hundred miles to Mammoth Lakes in California and my truck had that same knocking sound when I arrived at the campground. The knock only occurred during idle and not noticeable when the truck was accelerating. First time I have heard anything like this on my truck. Truck towed great without any problems with plenty of power. Towed trailer home without any problems and knocking during idle is gone. Truck idles smooth just like video shown by iflybeach. Thanks for both videos. Can a mechanical knock just disappear on its own or could this be a serious issue?
 

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iflybeach- How is your truck running now? Does it run smooth or do you get an occassional knock? I just got back towing my travel trailer approximately 300 hundred miles to Mammoth Lakes in California and my truck had that same knocking sound when I arrived at the campground. The knock only occurred during idle and not noticeable when the truck was accelerating. First time I have heard anything like this on my truck. Truck towed great without any problems with plenty of power. Towed trailer home without any problems and knocking during idle is gone. Truck idles smooth just like video shown by iflybeach. Thanks for both videos. Can a mechanical knock just disappear on its own or could this be a serious issue?
Its been purring like a kitten ever since.. This happened last Friday. It seemed to have plenty of power at the time and it was less noticeable with more RPM.. I didn't do anything to fix it.. I just revved the engine between those camera shots and when it came back to idle it just fixed itself. I am tending to think it was some sort of fuel contamination that finally got pushed through an injector or one of the sensors temporarily failed. Water in fuel? I am leaning towards water in fuel. I also add about 2 gallons a week of Jet-A that I sump off my airplane and I might have had a couple capfuls of water in the jet-A that I put in the night before..
 

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That is good to hear that your truck is running fine. Maybe my truck also encountered some minor fuel contaminate because it is running fine now. It did encounter a low oil pressure problem for a minute or so while towing a steep incline. My oil pressure guage started to fluctuate and behave erratically for a minute or so causing the low oil pressure to chime. It corrected itself and guage worked fine rest of the trip. I checked my oil and everything was good. I am going to take my truck to my mechanic to make sure the guage is working properly. Once again, it is good to hear your truck is running fine after that scare.
 

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not to derail, but what model Beech do you operate?
 

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Discussion Starter #11
not to derail, but what model Beech do you operate?
I used to fly a Travelair and a Bonanza.. for now I fly a Cessna Caravan.. Looking at a Beech King Air though..
 
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