Re: ISM450 120,000 mile service Reply #25 – January 04, 2022, 08:12:43 am The M11 and ISM DOES have a mechanical adjustment for the fuel injectors. It's covered in your engine owners manual and service manual. These engines do NOT have a high pressure fuel injection pump. There is a low pressure fuel pump driven off the end of the air compressor, 160 psi is what I remember. Each injector is a mechanical pump, driven off the camshaft, with an electrical solenoid that releases fuel into the engine. The longer the solenoid is pulsed open by the ECM the more fuel injected. Excess fuel is returned to the fuel tank. The mechanical adjustment is rather important but typically doesn't change after properly set. However if that adjustment is too tight it will damage that injector requiring injector replacement. I expect the ISX works the same way. Quote Selected 4 Likes
Re: ISM450 120,000 mile service Reply #26 – January 04, 2022, 10:39:57 am Good information if an injector has to be changed. Quote Selected
Re: ISM450 120,000 mile service Reply #27 – January 04, 2022, 11:30:50 pm Don't have either of these engines but sounds very Detroit Diesel regarding the cam driven injectors. No injection pump, never knew this. So, setting the clearances on injectors is kind of like running the rack? (with the addition of electronic injector control)? Quote Selected
Re: ISM450 120,000 mile service Reply #28 – January 05, 2022, 08:16:36 am Thanks David for the good information. Quote Selected
Re: ISM450 120,000 mile service Reply #29 – January 05, 2022, 05:08:26 pm Quote from: Chuck Pearson – January 04, 2022, 11:30:50 pm1. Don't have either of these engines but sounds very Detroit Diesel regarding the cam driven injectors. 2. No injection pump, never knew this. 3. So, setting the clearances on injectors is kind of like running the rack? (with the addition of electronic injector control)?Chuck, 1. After working on both over the years I would say they are verry similar2. The injector operation on this age engine is closer to how the injectors work on the Isuzu 3LD1 that are in some of our generators. But yes no real high pressure pump except in the injector.3. YesI have a set of instructions from school that explains how to set the injectors along with the valves and how to read the timing marks. If I could make this a pdf file I would post it as several DIY people here could use it. The purple Cummins book has the info but it is harder to understand than the school hand outs.Mike Quote Selected