Zippy63 Posted October 1, 2010 Share Posted October 1, 2010 Are injector cups in the head surrounded by the cooling system on the mp8? If so shouldn't u get fuel in the cooling system with a cracked cup? Quote Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/ Share on other sites More sharing options...
rhasler Posted October 1, 2010 Share Posted October 1, 2010 Are injector cups in the head surrounded by the cooling system on the mp8? If so shouldn't u get fuel in the cooling system with a cracked cup?The injector cups are surrounded by by coolant. Usually the cups don't crack, instead combustion gas from the cylinders tends to burn out the sealing washers at the base of the injectors causing the o-rings that seal the fuel passages to disentegrate and drop fuel from the injectors. Quote "Mebbe I'm too ugly and stupid to give up!" Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-64600 Share on other sites More sharing options...
fjh Posted October 1, 2010 Share Posted October 1, 2010 The injector cups are surrounded by by coolant. Usually the cups don't crack, instead combustion gas from the cylinders tends to burn out the sealing washers at the base of the injectors causing the o-rings that seal the fuel passages to disentegrate and drop fuel from the injectors.Theres More to the story , But Haslers holdin out on ya! Quote Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-64606 Share on other sites More sharing options...
rhasler Posted October 2, 2010 Share Posted October 2, 2010 Theres More to the story , But Haslers holdin out on ya! Yep. That's just the short version. Quote "Mebbe I'm too ugly and stupid to give up!" Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-64610 Share on other sites More sharing options...
Zippy63 Posted October 2, 2010 Author Share Posted October 2, 2010 What's the rest of the story. I like the technical side of the story Quote Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-64614 Share on other sites More sharing options...
Mackpro Posted October 2, 2010 Share Posted October 2, 2010 If you have a truck down with the bad cups, get the new style stainless steel cups and new style injectors. We have put several sets in. However today I had to pull a stainless cup out and replace it. The new cup didnt fail but the injector hold down bolt broke and the injector jumped around and damaged the cup. Quote Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-64616 Share on other sites More sharing options...
Zippy63 Posted October 2, 2010 Author Share Posted October 2, 2010 When I worked for ford, we use at tap with threads in the end of the tap for a slide hammer. Is it the same process, if so what size is? Quote Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-64618 Share on other sites More sharing options...
fjh Posted October 2, 2010 Share Posted October 2, 2010 If you have a truck down with the bad cups, get the new style stainless steel cups and new style injectors. We have put several sets in. However today I had to pull a stainless cup out and replace it. The new cup didnt fail but the injector hold down bolt broke and the injector jumped around and damaged the cup. We GOT a binder in the shop today one of the injector bolts fell out and flooded the muffler with fuel wonder if that will happen with the new injector cups?We got about 3 gallons of fuel out of the muffler! :)Imagine this happening to a dpf engine. Quote Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-64619 Share on other sites More sharing options...
Zippy63 Posted October 2, 2010 Author Share Posted October 2, 2010 If the seals are failing in the cups/ injector and compression gases are entering the fuel system, I should be able to install a clear hose on the return line at the fuel filter houseing and check for bubbles/gases returning to the tanks? Quote Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-64623 Share on other sites More sharing options...
Zippy63 Posted October 2, 2010 Author Share Posted October 2, 2010 In ur shop do u'll have paper manuals or are they on cd's, if so can u tell me where I can buy them? Quote Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-64624 Share on other sites More sharing options...
Zippy63 Posted October 2, 2010 Author Share Posted October 2, 2010 When installing the cup and injector, do I have to replace all of them? If so do the injectors have a calibration # that need to be programed into computer Quote Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-64625 Share on other sites More sharing options...
rhasler Posted October 2, 2010 Share Posted October 2, 2010 If the seals are failing in the cups/ injector and compression gases are entering the fuel system, I should be able to install a clear hose on the return line at the fuel filter houseing and check for bubbles/gases returning to the tanks?Yes, you can, and should, check for air in the fuel so as to make sure of where the air is entering the system.In ur shop do u'll have paper manuals or are they on cd's, if so can u tell me where I can buy them?Mostly electronic at the momentWhen installing the cup and injector, do I have to replace all of them? If so do the injectors have a calibration # that need to be programed into computerIf changing to steel injector cups all must be replaced. If this is the case you injector trim codes will need to be programmed as well (codes are on the injector wiring harness connector, four alpha-numeric characters). If replacing with copper cups the codes are already programmed, just keep them in the same cylinders they were removed from. DO NOT CLEAN THE INJECTOR TIPS, YOU WILL DAMAGE THE SPRAY PATTERN AND VOID YOUR WARRANTY. Quote "Mebbe I'm too ugly and stupid to give up!" Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-64627 Share on other sites More sharing options...
diesel9193 Posted November 15, 2016 Share Posted November 15, 2016 Have a question. If I'm replacing an injector on a 2013 MP8, do i have to reprogram it on the ECM or can i just replace it? Quote Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-352052 Share on other sites More sharing options...
ChicagoJohn Posted December 7, 2016 Share Posted December 7, 2016 3 months ago I had to replace all 6 injectors and cups on my 08. They were original with the copper cups and 2 were cracked. Everyone seems suprised that I got 825,000 on the originals. Quote Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-354293 Share on other sites More sharing options...
Mackpro Posted December 7, 2016 Share Posted December 7, 2016 On 12/8/2016 at 1:46 AM, ChicagoJohn said: 3 months ago I had to replace all 6 injectors and cups on my 08. They were original with the copper cups and 2 were cracked. Everyone seems suprised that I got 825,000 on the originals. Yea , I believe that a record! 1 Quote Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-354295 Share on other sites More sharing options...
220cummins Posted December 14, 2016 Share Posted December 14, 2016 Yes, when installing new injectors, the Calc Codes on the injectors will need to be updated in the ECM. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-355015 Share on other sites More sharing options...
little puppy Posted January 15, 2018 Share Posted January 15, 2018 would a 2011 mp8 be copper or conical? Thanks Quote Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-389716 Share on other sites More sharing options...
Mackpro Posted January 15, 2018 Share Posted January 15, 2018 If it has a DEF tank it has the stainless cups Quote Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-389720 Share on other sites More sharing options...
little puppy Posted January 15, 2018 Share Posted January 15, 2018 I have DEF, only got 395k mls, I'm pretty sure I'm getting seals leaking, my local mack said I probably need all new injectors ext ext @ $6 grand. Truck runs great, so why do I need to change all 6 injectors if there not bad? Can't I just do new cup seals? Thanks for your help! Quote Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-389722 Share on other sites More sharing options...
tristate concrete Posted April 17, 2019 Share Posted April 17, 2019 (edited) Got a 2012 mac mp7 on a concrete pump with 65k miles. smoking like a 12 valve cummins...... keeps over heating . heard theres 27 revisions on the injector s lol. added coolant still over heating. replaced thermostat but still bad. and ideas? Edited April 17, 2019 by tristate concrete Quote Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-420754 Share on other sites More sharing options...
JoeH Posted April 17, 2019 Share Posted April 17, 2019 8 hours ago, tristate concrete said: Got a 2012 mac mp7 on a concrete pump with 65k miles. smoking like a 12 valve cummins...... keeps over heating . heard theres 27 revisions on the injector s lol. added coolant still over heating. replaced thermostat but still bad. and ideas? Hey don't make fun of my 12 valve! It only smokes a pretty black cloud when you goose it, and just for a second til the turbo catches up to the fuel! And that's with 218k miles! Quote Link to comment https://www.bigmacktrucks.com/topic/15980-injector-cups-mp8/#findComment-420760 Share on other sites More sharing options...
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