Joe2007 Posted June 30 Share Posted June 30 Hey guys I have a 1990 Mack ch600 with a E7-300 I drive the truck just about everyday. I’ve started have some trouble with it but can’t figure it out. It starts and runs good not smoking out anything. The trouble I’m having is it’s got no power. Same routs everyday the hills I was climbing at 30mph I’m now climbing around 18 or 19mph and it’s the same way loaded or unloaded. Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/ Share on other sites More sharing options...
Joey Mack Posted June 30 Share Posted June 30 Fuel filters? 1 Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-578251 Share on other sites More sharing options...
Joe2007 Posted June 30 Author Share Posted June 30 I changed both of them. Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-578252 Share on other sites More sharing options...
mechohaulic Posted June 30 Share Posted June 30 fuel tank vent clogged creating vacuum / flex line in suction side has internal split line restricting flow? one tank or two? 1 Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-578256 Share on other sites More sharing options...
fjh Posted June 30 Share Posted June 30 11 hours ago, Joe2007 said: Hey guys I have a 1990 Mack ch600 with a E7-300 I drive the truck just about everyday. I’ve started have some trouble with it but can’t figure it out. It starts and runs good not smoking out anything. The trouble I’m having is it’s got no power. Same routs everyday the hills I was climbing at 30mph I’m now climbing around 18 or 19mph and it’s the same way loaded or unloaded. what trans do you have and do you have any fault lights ? If no faults and If You have a Mack trans >try disconnecting the torque limit switch on the rear of the trans Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-578257 Share on other sites More sharing options...
terry Posted June 30 Share Posted June 30 Loosing boost somewhere? terry Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-578258 Share on other sites More sharing options...
fjh Posted June 30 Share Posted June 30 1 minute ago, terry said: Loosing boost somewhere? terry Terry ! runs good not smoking out anything 1 Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-578259 Share on other sites More sharing options...
Joe2007 Posted June 30 Author Share Posted June 30 No faults. 10 speed. It’s got 2 110 gal tanks. But I have one of them turned off have not used it for a couple years. Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-578267 Share on other sites More sharing options...
fjh Posted June 30 Share Posted June 30 37 minutes ago, Joe2007 said: No faults. 10 speed. It’s got 2 110 gal tanks. But I have one of them turned off have not used it for a couple years. Sorry just noticed year is it vmac ? If not check throttle lever for going full on and stop for full on! Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-578271 Share on other sites More sharing options...
Joe2007 Posted June 30 Author Share Posted June 30 What are you talking about Vmac? Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-578280 Share on other sites More sharing options...
fjh Posted June 30 Share Posted June 30 Electric fuel pump! Likley not because of the year! That said the lda ont the top rear may be at issue here! Let us know! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-578283 Share on other sites More sharing options...
JoeH Posted June 30 Share Posted June 30 7 hours ago, fjh said: Terry ! runs good not smoking out anything Check boost, could have a crack in the Charge Air Cooler. My '95 e7-350 was a whole different engine when we replaced our cracked CAC. Went from 22psi to peaking around 34 psi under certain conditions. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-578292 Share on other sites More sharing options...
Joe2007 Posted June 30 Author Share Posted June 30 What’s the best way to check for boost leaks? Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-578293 Share on other sites More sharing options...
fjh Posted June 30 Share Posted June 30 4 minutes ago, Joe2007 said: What’s the best way to check for boost leaks? If. You don’t have smoke most likely a fuel issue just sayin Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-578294 Share on other sites More sharing options...
Joey Mack Posted June 30 Share Posted June 30 Some, on here have made pressure testers with PVC parts. If you do that, keep in mind that when you get near 10 psi, these home made tools can pop off with a vengeance. So build it smartly. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-578295 Share on other sites More sharing options...
Joey Mack Posted June 30 Share Posted June 30 https://www.googleadservices.com/pagead/aclk?sa=L&ai=DChsSEwi33eflmZqOAxXENggFHZ74B_kYACICCAEQIBoCbWQ&co=1&gclid=Cj0KCQjw64jDBhDXARIsABkk8J5pZuKDpgTeenxDmarE-L3O9LxHZdQp20D5JsrUALy4EhfFWHue3GsaAjjfEALw_wcB&sph=&ohost=www.google.com&cid=CAESwwHg9oUHqV36uRgSbbvkbz72M298ShJHG6glAhlB2DjLhlV346HFyHELH3S57AH-duG7SDnYsKL4gj0yOs1JiPiyoIak7aemnZkFjfdpuUm3KGxRWRAfchUt_6vrk9eRZ6EQN8Q0YC3vSQpjmtorPahrV-nG8Epg864ofPlSW6fktY0NIL1hU33jHc0A7KLASjlAVkubZFnUxG9ODW-6d4wOG4VUgje7XanFgMHdajWtbBlWM0l00Ndk8L5dFEFrO55P7O0&category=acrcp_v1_41&sig=AOD64_22SWCMH_4znJO98E2Gu73cxEunzQ&ctype=5&q=&ved=2ahUKEwizqeHlmZqOAxVYq4kEHfOOG7kQwg8oAHoECAoQHw&adurl= Here is a sample of a pressure tester. I have a Pro Set, but this may be good enough for you, and be a good addition to the tool box. There are many other choices.... Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-578296 Share on other sites More sharing options...
fjh Posted June 30 Share Posted June 30 (edited) 1 hour ago, Joey Mack said: Some, on here have made pressure testers with PVC parts. If you do that, keep in mind that when you get near 10 psi, these home made tools can pop off with a vengeance. So build it smartly. Oh ya! 😡 Found a gusher with this setup! By the way this is not my set up how ever he is a member here I have been helping him with his issue in this case lots of smoke lacking boost! Edited June 30 by fjh 1 1 Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-578298 Share on other sites More sharing options...
JoeH Posted July 1 Share Posted July 1 23 hours ago, Joe2007 said: What’s the best way to check for boost leaks? High pyrometer temps (1100+) and low boost mean not enough air. My e7-350 went from 1200+/22psi to 900/35 when I found/replacedy cracked CAC. 2 Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-578348 Share on other sites More sharing options...
mrsmackpaul Posted July 2 Share Posted July 2 It sounds t like the rack isn't shifting far enough I would expect if the intercooler had a air leak it would be making lots of smoke underload I would be looking for something obvious like the injector pump isn't getting pushed around far enough when the foots to the floor It sounds like something is preventing this from happening Paul Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-578362 Share on other sites More sharing options...
Joe2007 Posted September 23 Author Share Posted September 23 I’ve replaced throttle cable fuel filters nothing has changed it has no power loaded or empty. It will get up to speed, but it takes it forever. it does not smoke at all. I’m not sure when you push the throttle down and it moves the lever on the pump all the way forward I do see a little bit of oil in my air cooler. Could that be causing me some trouble? Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-583261 Share on other sites More sharing options...
fjh Posted September 23 Share Posted September 23 56 minutes ago, Joe2007 said: I’ve replaced throttle cable fuel filters nothing has changed it has no power loaded or empty. It will get up to speed, but it takes it forever. it does not smoke at all. I’m not sure when you push the throttle down and it moves the lever on the pump all the way forward I do see a little bit of oil in my air cooler. Could that be causing me some trouble? Not likly! You would likely have smoke if it were a turbo issue! Fuel pressure check? Also the smoke limit device at the top rear of the fuel pump ! It could have a hole in the diaphragm best way to check this is to take the air line off it and suck or blow through it if you can blow through it needs a replacement diaphragm! Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-583264 Share on other sites More sharing options...
Joe2007 Posted September 23 Author Share Posted September 23 What’s the easiest way to check the fuel pressure and where do you hook up at? Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-583267 Share on other sites More sharing options...
fjh Posted September 23 Share Posted September 23 11 minutes ago, Joe2007 said: What’s the easiest way to check the fuel pressure and where do you hook up at? You need to t into the inlet line of the pump! Did you check the smoke limit tube! Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-583270 Share on other sites More sharing options...
Joey Mack Posted September 23 Share Posted September 23 have you checked the throttle arm on the pump to see if it is moving all the way to the stop screw, and have some pressure on the spring to insure that it is at W.O.T. ? Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-583273 Share on other sites More sharing options...
fjh Posted September 23 Share Posted September 23 3 minutes ago, Joey Mack said: have you checked the throttle arm on the pump to see if it is moving all the way to the stop screw, and have some pressure on the spring to insure that it is at W.O.T. ? Joey he mentioned this above! (I’m not sure when you push thethrottle down and it moves the lever on the pump all the way forward) 1 Quote Link to comment https://www.bigmacktrucks.com/topic/75724-power-problems/#findComment-583274 Share on other sites More sharing options...
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