We have 2 buses that have been sitting since May when school was let out and have only been started once since then. I went out today to try to start them but they both crank but no start. When cranking the oil pressure gauge gradually builds but doesnt reach past 20 psi. I am new to school buses and especially the maxxforce engines. One unit is a 2012 with roughly 30,000 miles and the other one is a 2009 with 78,000 miles. Any idea what could cause the issue? Both buses were running fine when parked both have morning and afternoon routes and we havent had any issues before this.
Welcome the club of MaxxFarce junk. I assume you are talking about MaxxFarce 9's. These things are notorious for this problem and most of believe it is fuel draining back to the tank. I have 5 here and I let them sit since may until two weeks ago and had the same issue. After a ton of cranking they finally started. I had the same issue with a dozen or so in the last system I was in. Start them often or find out why the fuel drains back.
What MaxxForce are you talking about? I assume that RonF knows what he's talking about because he has had the same problem, but if it isn't a Maxxforce 9, you will need to look at different things for different engines.
It seems I've heard mention of a check valve located in the filter housing block, or some area. I might not be thinking of the same thing, but I've heard that you have to change the entire block if the check valve malfunctions. Does this sound familiar to any Maxforce people?
I have had the maxxforce dt -07 epa engines with the primer pump/ fuel filter housing assy are the ones we have had this issue on the fuel draining back ***but they always start for me just is an extended crank mabey 10-15 seconds at first start ---Sounds like its either that or some type of high press oil issue seeing you said they get to 20 psi possible leak but could be separate issues ---let em sit and before you start them pull the fuel filters should be empty if the fuel is draining back I believe
Open the fuel filter housing and see if it`s empty. I have a fleet of 25 maxforce DTs and never had that problem , i did have an extended crank on a DT that sat for 1-1/2 years do to a crash in the side but like was said 10 to 15 seconds of cranking and it was running. What is you cranking fuel pressure and injection control pressures??