MCHAM Posted May 28, 2011 Share Posted May 28, 2011 I have a 1992 RD690s quad axle with the E7300 and 7 speed trans. When I got the truck it was rolling blk smoke when going down the road, but it clear after you change all the gears. So I was told to change the injectors, had them rebuild & the rack was ran. The truck stills smokes but not as bad. So today everytime I got loaded the truck would smoke like a tire on fire, and her power was way down. Get the load off her back and power was back. I don't know what to do. This is my first truck. Can somebody help me out. Quote Link to comment Share on other sites More sharing options...
rhasler Posted May 28, 2011 Share Posted May 28, 2011 Sounds like you may be lacking for clean air going into the engine. Check the air cleaner for restrictions and the charge air cooler and piping for holes. Quote "Mebbe I'm too ugly and stupid to give up!" Link to comment Share on other sites More sharing options...
theakerstwo Posted May 28, 2011 Share Posted May 28, 2011 And after you make sure itr dont have a boost leak on the coller plumbing make sure that the hose from the intake to the air compressore is not leaking boost. The i would pull the exhaust and intake off of the turbo and look at both ends. Look at the exhaust wheel and make sure there is no tips bent of missing on the exhuast wheel. Quote glenn akers Link to comment Share on other sites More sharing options...
MCHAM Posted May 28, 2011 Author Share Posted May 28, 2011 Went over everything and found no leaks. Buddy of mine hooked up a boost gage and the truck is showing it's make 11-12psi unloaded. Is this the nomal boost range? He thinks the timing is off on the truck. The truck has new fuel & air filters also. Quote Link to comment Share on other sites More sharing options...
Lmackattack Posted May 28, 2011 Share Posted May 28, 2011 No, that's way low.18-23 psi is normal boost.21 is about avg. turned up pump is 25 psi...Check the turbo like said above. I had a housing melt away allowing exhaust to bypass the blades and thus no boost over 14 psi could be made... Quote Link to comment Share on other sites More sharing options...
fjh Posted May 28, 2011 Share Posted May 28, 2011 No, that's way low.18-23 psi is normal boost.21 is about avg. turned up pump is 25 psi...Check the turbo like said above. I had a housing melt away allowing exhaust to bypass the blades and thus no boost over 14 psi could be made... Yup check for leaks or the turbo your way down on boost!You need to preasure up the intake side of the engine with at least 20 psi to fined leaks properly how are you checking it? Quote Link to comment Share on other sites More sharing options...
theakerstwo Posted May 29, 2011 Share Posted May 29, 2011 Like done been stated pressure test the intake system in stead like some guys do by looking at it.Then also check the throdle linkage if its a manual pump for full throdle. Quote glenn akers Link to comment Share on other sites More sharing options...
MCHAM Posted May 30, 2011 Author Share Posted May 30, 2011 Well guys, the guy working on my truck thinks my problem is in the injector pump. That's why the truck is over fueling when it gets aload on it. When you back off the gas some it some of the smoke clears up and you have to the truck build speed like that. He was saying when he was cracking on the lines #2 goes to flutting abit. I'm new to this, but I'm trying to learn as much as I can. I just had the injectors done, and ran the rack. He checked all the lines, hose, and the turbo. In the morning I'm taking it to a guy that does injector pumps, I'm about to go trucks with this truck!!! Quote Link to comment Share on other sites More sharing options...
fjh Posted May 31, 2011 Share Posted May 31, 2011 Well guys, the guy working on my truck thinks my problem is in the injector pump. That's why the truck is over fueling when it gets aload on it. When you back off the gas some it some of the smoke clears up and you have to the truck build speed like that. He was saying when he was cracking on the lines #2 goes to flutting abit. I'm new to this, but I'm trying to learn as much as I can. I just had the injectors done, and ran the rack. He checked all the lines, hose, and the turbo. In the morning I'm taking it to a guy that does injector pumps, I'm about to go trucks with this truck!!!Hope Hes Right! Quote Link to comment Share on other sites More sharing options...
theakerstwo Posted May 31, 2011 Share Posted May 31, 2011 Hope Hes Right! I hear you. Quote glenn akers Link to comment Share on other sites More sharing options...
MCHAM Posted June 10, 2011 Author Share Posted June 10, 2011 Yeap he was right the problem was in the pump. Replaced a part on the back of the pump and the smoke cleared up. Got a half a day work out of the truck. Guess what? I got me a reman pump from Mack and it's going on Monday. So if the Lord is willing I can run problem free for a while. Quote Link to comment Share on other sites More sharing options...
Mike Posted June 11, 2011 Share Posted June 11, 2011 Makes me wonder if a pump can be bought for less at Mack than at a pump shop? I will probably need this service in the future. mike Quote Link to comment Share on other sites More sharing options...
rhasler Posted June 11, 2011 Share Posted June 11, 2011 Yeap he was right the problem was in the pump. Replaced a part on the back of the pump and the smoke cleared up. Got a half a day work out of the truck. Guess what? I got me a reman pump from Mack and it's going on Monday. So if the Lord is willing I can run problem free for a while.Air fuel control diaphragm? Quote "Mebbe I'm too ugly and stupid to give up!" Link to comment Share on other sites More sharing options...
fjh Posted June 11, 2011 Share Posted June 11, 2011 Air fuel control diaphragm?The LDA will repair the smoke problem to some degree but maybe not the power.Glad ya found the problem Maybe? Quote Link to comment Share on other sites More sharing options...
MCHAM Posted June 11, 2011 Author Share Posted June 11, 2011 I went with a mack pump due to the fact I could get one the next day vs rebuilding my pump and my truck would have been down bout a week. If da wheels ain't turning you ain't earning Quote Link to comment Share on other sites More sharing options...
MCHAM Posted June 17, 2011 Author Share Posted June 17, 2011 Well I got my truck back this morning. All I can say is she is running like a raped ape!! Fires up when I turn the key, and the power is there. I can get a speeding ticket now!!! Quote Link to comment Share on other sites More sharing options...
fundadtn Posted June 18, 2011 Share Posted June 18, 2011 I have a 1992 RD690s quad axle with the E7300 and 7 speed trans. When I got the truck it was rolling blk smoke when going down the road, but it clear after you change all the gears. So I was told to change the injectors, had them rebuild & the rack was ran. The truck stills smokes but not as bad. So today everytime I got loaded the truck would smoke like a tire on fire, and her power was way down. Get the load off her back and power was back. I don't know what to do. This is my first truck. Can somebody help me out.My FIRST suggestion is to take the air cleaners out and try it. If that clears up the problem than you know what caused it. When I was in the trucking business I had more than one shop try to sell me injectors, and turbochargers in similar problems, and sometimes it was an injector or turbo, but pretty rarely, because I watched the exhaust stacks and other symptomatic areas when the trucks were on my yard. An injector should smoke all the time,,, just like a turbocharger would. If the air cleaners don't fix the problem, check the boost pressure line going from the intake manifold to the pump. When the boost pressure is low, it will sometimes allow more fuel into the injectors. Likewise when the boost (manifold pressure) pressure is high, it will automatically decrease the amount of fuel flow through the pump.Hope this helps.Dan. Quote Link to comment Share on other sites More sharing options...
MCHAM Posted June 18, 2011 Author Share Posted June 18, 2011 Hey Dan, my problem was my injector pump. Quote Link to comment Share on other sites More sharing options...
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