Dirtymilkman Posted August 17, 2022 Share Posted August 17, 2022 2015 MP10, cold starts great, warms starts good most of the time. But, on an upward incline, if it sits for 10 minutes it'll crank and sputter and crank. Sounds like a gas engine that's flooded. Then it will fire and take a second to clear out. 600,000 miles, 500,000 on injectors. Runs great, no power loss, no smoke. The upward incline thing puzzles me. Quote Link to comment Share on other sites More sharing options...
Mackpro Posted August 17, 2022 Share Posted August 17, 2022 Had a similar MP 10 issue years back. However In our case I don’t think any incline was a factor. I’m thinking it was exhaust rocker arms were the problem. I know there was a service bulletin on upgraded injector o-rings that are only used on the MP10. I’ll probably talk to the guy in the morning that worked on it . Hopefully he will remember. . 1 Quote Link to comment Share on other sites More sharing options...
Mackpro Posted August 17, 2022 Share Posted August 17, 2022 Talked to the Tech this morning . About 5-6 years ago we had a 2013 Titan MP10 that spun a main bearing. They installed a Mack Basic Reman engine. Reused the turbo and injectors. Shortly afterwards the engine would start fine but after about 20 seconds it would stumble and sometimes die , it would take about another 20 seconds for it to clear up and run right . It was the exhaust rocker arms. We still had the core motor so we pulled the complete rocker arm shaft off and installed it on the reman motor and all was good . Found the reman engine did not have the newest part number rockers on it . Ordered the new ones, installed them and all was good. In September of 2015 mack released a bulletin and tool for new upgraded special o-rings for the injectors. No mention of the symptoms for this update other than to help with injector cups blowing 1 1 Quote Link to comment Share on other sites More sharing options...
Dirtymilkman Posted August 17, 2022 Author Share Posted August 17, 2022 Thanks for checking. They told me to pressurize the injection system so that may be the next step. Quote Link to comment Share on other sites More sharing options...
Mackpro Posted August 17, 2022 Share Posted August 17, 2022 I’ve had to that a couple of times due to a batch of bad reman injectors. Plugged the fuel outlet in the front of the head and hooked up a air pressure regulator going into the fuel galley and set to 65 psi and shot air into the injectors. We sprayed soapy water down in the injector spring looking for bubbles. We also bumped the engine over to check both when the injector is pushed down and in the up position. One truck with leaking injectors would only do the start and die issue when the fuel tanks we’re below 3/4 full. And of course there were signs of fuel in the oil but not as much as I would think Quote Link to comment Share on other sites More sharing options...
Dirtymilkman Posted August 17, 2022 Author Share Posted August 17, 2022 5 hours ago, Mackpro said: I’ve had to that a couple of times due to a batch of bad reman injectors. Plugged the fuel outlet in the front of the head and hooked up a air pressure regulator going into the fuel galley and set to 65 psi and shot air into the injectors. We sprayed soapy water down in the injector spring looking for bubbles. We also bumped the engine over to check both when the injector is pushed down and in the up position. One truck with leaking injectors would only do the start and die issue when the fuel tanks we’re below 3/4 full. And of course there were signs of fuel in the oil but not as much as I would think They said I can start right at the fuel line off the tank first with low pressure. He mentioned the Davco filter could be doing it? Quote Link to comment Share on other sites More sharing options...
fjh Posted August 18, 2022 Share Posted August 18, 2022 3 hours ago, Dirtymilkman said: They said I can start right at the fuel line off the tank first with low pressure. He mentioned the Davco filter could be doing it? Yup! Quote Link to comment Share on other sites More sharing options...
Mackpro Posted August 18, 2022 Share Posted August 18, 2022 I seem like I like to blame everything on cups and injectors but in my defense, here’s what I have encountered at my day job here lately. 90% of our trucks are out of warranty so we are repairing what we can till our new trucks arrive, which will probably be Spring of next year. Last week I had 2 different 2016 CXU’s MP8 with the classic hard start complaint . Each truck had 2 cups leaking and pitted injectors so replaced the bad cups and injectors and reinstalled remaining injectors with new o-rings and hold down bolts . Not to bad a job to do . I have a buddy with his own shop and works on everything ( Cats, Cummins,Detroit) but Mack/Volvo. He calls me last week and I spend a couple nights on a 2010 GU MP7 with coolant in fuel and fuel in coolant. . Yank cups out and o-rings on them are shot. New cups and luckily the injectors were OK . Re-assembled and flushed cooing system and block and fuel tanks and back on the road . Then Wednesday/Thursday night I’m on a 2016 Volvo D-13 , hard start and 3 blown cups/ pitted injectors, done and on the road . This week at the day job. 2013 CXU MP8 engine miss, injector code for #1 . Got engine hot, yanked valve cover , did electrical test on injectors and 5 of the 6 were bad . Replacing all . Should be done with that one tomorrow. Night job this week involved another 2016 Volvo D13 hard starting , 3 cups and pitted injectors on it as well. Hope to have it done by tomorrow night or Friday night . Fun times ! Lol Quote Link to comment Share on other sites More sharing options...
Dirtymilkman Posted August 18, 2022 Author Share Posted August 18, 2022 Too bad they're not as easy to replace as an e7 Quote Link to comment Share on other sites More sharing options...
fjh Posted August 21, 2022 Share Posted August 21, 2022 Cupdemic!🤣 for you soon there will be a cup shortage ! your useing them up! They need to be a stocking item at your place! MP Quote Link to comment Share on other sites More sharing options...
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