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Discussion Starter #1
I was running down the interstate about 65. The truck lost power started to grey smoke like a freight train. As I was slowing down in the emergency lane it started to knock. I shout the truck down checked for leaks. I didn't find anything. I found no coolant or oil leaking that I could see. Said the hell with it need to get the truck and trailer of the side of the interstate. When I cranked it up it. It didn't knock at first but about 5 seconds after it started it began to knock, continued to get louder for the next 5-10 seconds, then leveled off. I ended up leaving the truck in a parking lot and calling a buddy to get me and the bull i was hauling. It's not a rod knock it sounds like a fuel knock to me. I have heard about some VP's taking a dump and the delivery valves sticking causing an injector to stick wide open. Also I was thinking maybe an injector went south or head gasket possibly the head gasket blew and the sound is compression leaking out. Im gonna check it out some later today when I get home.

The truck has 7x.010 sdx's, ED 62/68/13, so vp, and an airdog 165, and a drag comp.

Any one have any ideas or thoughts on were to check first let me know.
Thanks
Randy
 

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Discussion Starter #2
I just had an after thought. Theres no water in the oil. At the time the truck was at operating temp I didn't think to look at the cooling system to see if it was pressurized.
 

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Given the no water in the oil but a loss of power and grey smoke sounds like an injector but the knock throws me off.
 

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Discussion Starter #4
Yeah that's what has me thrown through a loop. I talked I to Tony Johnson today. He owns a small diesel shop in Tennessee. Several other people in the Tennessee chapter deal with him. He said he would bet on the pump. He said he has replaced several vp's that have done this and causing injectors to fail. He said the knock is because the timing is all out of whack due to the injector jammed open and the pump dumping fuel. I'm going to swap pumps and injectors between my two trucks and check the head bolts and go from there. I was just wanting to get some other opinions before I started disassembly.
 

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have Injectors tested or find a set to try. Leaking injector causes fuel knock. You can loosen each line and see if knock goes away on one line. VP issues cause miss, and smoke. Don't get thrown under the truck with high cost misdiagnois.
 

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Yeah if you have another set to throw in there try that and see if it helps. If not then could be the pump. I know when mine went out i had the smoke and power loss but no knock. You may get lucky and it be an injector though, I wish that was all mine was.... $1800:$::$:

Blue Chip Diesel Performance Specialists
 

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I'm new to the forum but I've been around trucks my whole
Life. I just went through the same thing and, not saying for sure that this is the issue but, when we pulled my head, thinking it was a head gasket, we found that two pistons had began to melt down. Oil was clearly pushing past them and there wasn't any compression. Burning oil caused my grey smoking issue and I'm going through a full build currently. I wouldn't be afraid to go ahead and pull the head and check it out. And maybe stud it while your in there. Especially if you do a lot of towing and see high egts/oil temp.
 

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Discussion Starter #8
I think I found the culprit. The #5 cylinder had a broken nozzle. Has any one run in to this before or know what maybe caused it. I think maybe bad fuel. Water in the fuel turned to steam cracking the nozzle.


 
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