Mjgrading Posted December 15, 2017 Share Posted December 15, 2017 Just installed a boost guage and plumbed it to the manifold. Running 15-16 psi. That as good as it gets? Quote Link to comment https://www.bigmacktrucks.com/topic/51963-em7-300-e-tech-boost-pressure/ Share on other sites More sharing options...
j hancock Posted December 16, 2017 Share Posted December 16, 2017 Double check all the connections and the cooler for leaks. Believe it is closer to 18-22 boost under load. Quote JimIt doesn't cost anything to pay attention. Link to comment https://www.bigmacktrucks.com/topic/51963-em7-300-e-tech-boost-pressure/#findComment-387574 Share on other sites More sharing options...
Mjgrading Posted December 18, 2017 Author Share Posted December 18, 2017 All connections are good. Can’t find any leaks in the cooler. Quote Link to comment https://www.bigmacktrucks.com/topic/51963-em7-300-e-tech-boost-pressure/#findComment-387674 Share on other sites More sharing options...
Mjgrading Posted December 19, 2017 Author Share Posted December 19, 2017 (edited) Soooooo...this truck is driving me crazy. Running through the gears (it’s a 7 speed) it’s only making 15-16 psi. Then once yesterday and today I’m in high gear, empty, around 55-65 mph and it hits 22-23psi. It’s only hit that much twice. Edited December 19, 2017 by Mjgrading Quote Link to comment https://www.bigmacktrucks.com/topic/51963-em7-300-e-tech-boost-pressure/#findComment-387745 Share on other sites More sharing options...
Dirtymilkman Posted December 19, 2017 Share Posted December 19, 2017 Fuel filters could need replacing. Quote Link to comment https://www.bigmacktrucks.com/topic/51963-em7-300-e-tech-boost-pressure/#findComment-387749 Share on other sites More sharing options...
Mackpro Posted December 20, 2017 Share Posted December 20, 2017 The early ETECHs had bad problems with intake manifold gaskets blowing out. Also remember all ETECH, CCRS and AI engines had the air compressor intake piped into the turbo boost pressure side of the intake system. Any leak at this piping will result in low turbo boost Quote Link to comment https://www.bigmacktrucks.com/topic/51963-em7-300-e-tech-boost-pressure/#findComment-387778 Share on other sites More sharing options...
2000CL713 Posted December 20, 2017 Share Posted December 20, 2017 5 hours ago, Mackpro said: The early ETECHs had bad problems with intake manifold gaskets blowing out. Also remember all ETECH, CCRS and AI engines had the air compressor intake piped into the turbo boost pressure side of the intake system. Any leak at this piping will result in low turbo boost how would you go by checking the air compressor for leaks that could cause low boost? Quote Link to comment https://www.bigmacktrucks.com/topic/51963-em7-300-e-tech-boost-pressure/#findComment-387795 Share on other sites More sharing options...
Mackpro Posted December 20, 2017 Share Posted December 20, 2017 (edited) You remove the turbo to after cooler pipe and install test plug on to after cooler, leave all other piping alone., hook up air pressure regulator and pump 30 psi into after cooler/ rest of engine. Spray soapy water on intake gaskets and around air compressor intake piping and back of engine. Due to intake and exhaust valves being open in engine it might not hit 30 psi but it will be good enough to find leaks Edited December 20, 2017 by Mackpro Quote Link to comment https://www.bigmacktrucks.com/topic/51963-em7-300-e-tech-boost-pressure/#findComment-387838 Share on other sites More sharing options...
Mack Technician Posted December 20, 2017 Share Posted December 20, 2017 Give the turbo impeller a spin too. Most of the time the turbo either puts up or gives up (chunks). On occasion we have found a turbo gaining drag in it's center bearing. When I tuned up my buddies '98 PLN the compressor side was slowly chewing itself skinny, but had not blown and still made enough boost to pull. Don't look at center slop/play.....only house contact. Quote Link to comment https://www.bigmacktrucks.com/topic/51963-em7-300-e-tech-boost-pressure/#findComment-387841 Share on other sites More sharing options...
theakerstwo Posted December 20, 2017 Share Posted December 20, 2017 2 hours ago, Mackpro said: You remove the turbo to after cooler pipe and install test plug on to after cooler, leave all other piping alone., hook up air pressure regulator and pump 30 psi into after cooler/ rest of engine. Spray soapy water on intake gaskets and around air compressor intake piping and back of engine. Due to intake and exhaust valves being open in engine it might not hit 30 psi but it will be good enough to find leaks Watch your pressure gauge and turn engine slow till you get max pressure .You can find a place were enough valves wether intake or exhaust will be closed to build pressure on all cyl. Quote glenn akers Link to comment https://www.bigmacktrucks.com/topic/51963-em7-300-e-tech-boost-pressure/#findComment-387849 Share on other sites More sharing options...
Lmackattack Posted December 21, 2017 Share Posted December 21, 2017 my 285 tip turbine puts out 23psi under load. Quote Link to comment https://www.bigmacktrucks.com/topic/51963-em7-300-e-tech-boost-pressure/#findComment-387858 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.