Mark T Posted January 7, 2023 Share Posted January 7, 2023 Bottom line..... cold needs rich fuel mixture. So if after a turbo the air doesn't get exposed to ambient temp, it's theoretically warmer. (think poor man's glo plug) and then Mack had all sorts of ways to interrupt the rack's amount of travel in mechanically governed engines. ( be it to start or on the old extended range transmission models ) Old extended range transmissions with crazy low gears , nothing rearward of them could withstand as much torque multiplication as all that gearing could supply let alone any torque from the engine too . Now ???? all this can be actuated at the speed of light with an ECM. Quote Link to comment https://www.bigmacktrucks.com/topic/70046-charge-air-cooler-bypass/page/2/#findComment-520247 Share on other sites More sharing options...
95RD Posted March 20, 2023 Share Posted March 20, 2023 Thank you for the information. I was able to learn a lot from this. I am having issues with "sluggishness" when loaded. I am in the process checking my LDA per the video instruction. I think I have a leak in the hose or in my LDA valve. My question, is there a way to trick the LDA permanently? To allow for full rack all the time. Quote Link to comment https://www.bigmacktrucks.com/topic/70046-charge-air-cooler-bypass/page/2/#findComment-527558 Share on other sites More sharing options...
fjh Posted March 20, 2023 Share Posted March 20, 2023 You could apply 30 psi regulated air to it ! You can also take the small cap off the end two screws under that is the start position screw screw it in! Quote Link to comment https://www.bigmacktrucks.com/topic/70046-charge-air-cooler-bypass/page/2/#findComment-527567 Share on other sites More sharing options...
95RD Posted March 21, 2023 Share Posted March 21, 2023 Thank you!! I will try that. I will keep y’all updated. Quote Link to comment https://www.bigmacktrucks.com/topic/70046-charge-air-cooler-bypass/page/2/#findComment-527575 Share on other sites More sharing options...
fjh Posted March 21, 2023 Share Posted March 21, 2023 12 hours ago, 95RD said: Thank you!! I will try that. I will keep y’all updated. yup So the issue with the air fix is if the the diaphragm is burst inside you won't Know! To check the diaphragm simply suck or blow on the hose if it won't hold a vacuum or you can blow thru it the diaphragm is toast! in evet the diaphragm still holds air , If you need to just take the edge off the sluggishness remove the two screw cap at the rear and turn the screw in 1/4 turn at a time! NOTE !This will still not repair the sluggishness if the diaphragm has a hole in it! proper fix is to replace the diaphragm! Just sayin! Quote Link to comment https://www.bigmacktrucks.com/topic/70046-charge-air-cooler-bypass/page/2/#findComment-527594 Share on other sites More sharing options...
95RD Posted March 21, 2023 Share Posted March 21, 2023 1 hour ago, fjh said: yup So the issue with the air fix is if the the diaphragm is burst inside you won't Know! To check the diaphragm simply suck or blow on the hose if it won't hold a vacuum or you can blow thru it the diaphragm is toast! in evet the diaphragm still holds air , If you need to just take the edge off the sluggishness remove the two screw cap at the rear and turn the screw in 1/4 turn at a time! NOTE !This will still not repair the sluggishness if the diaphragm has a hole in it! proper fix is to replace the diaphragm! Just sayin! Yes! That is the first think I am checking (and the supply hose from the intake) before I do anything to it. Quote Link to comment https://www.bigmacktrucks.com/topic/70046-charge-air-cooler-bypass/page/2/#findComment-527599 Share on other sites More sharing options...
67RModel Posted March 21, 2023 Author Share Posted March 21, 2023 1 hour ago, 95RD said: Yes! That is the first think I am checking (and the supply hose from the intake) before I do anything to it. Another thing to look for if the supply hose to the LDA checks out OK is the torque limiting valve (if you have one). If its faulty it could be permanently dumping your boost pressure to the LDA regardless of what gear you are in. I don't know if these fail and if they do what is their mode of failure is. You could check it by capping the line running from the manifold back to the transmission. This will take the torque limiting valve out of the equation for diagnostic purposes. If your sluggishness improves you might have a bad torque limiting valve. As I said before I don't know how common this really is though but easy to check. Quote Link to comment https://www.bigmacktrucks.com/topic/70046-charge-air-cooler-bypass/page/2/#findComment-527600 Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.