Midwest Farms

New solenoid is $500! I may live with it unless it fails to start in the colder months. Thanks again for the input. Much appreciated.

Thanks BR549 and FJH, you appear to both be spot on. It appears to be the solenoid or an oil antidrain back valve (check value) at minimum. The truck will run rough until the oil pressure picks up. On a cold motor, it takes about 4-5 seconds for the oil pressure gauge to move and it smooths out right as the oil pressure gauge begins to move. I'm speculating this 4-5 seconds is how long it takes the sump to pump oil to the injection pump. Oil pressure is good otherwise. Also, if trying to restart the truck after sitting for 30 minutes, it fires right up. So if I understand this correctly, the issue may be the solenoid failing to shuttle due to no oil pressure at startup to actuate it. Is there an oil anti-drain valve or check value that could be causing this issue? If I'm headed in the wrong direction on this one, feel free to call me out. Thanks again for the help. We are a new small business and this forum is a huge help in keeping things moving! Also, are there any online manuals for these motors or do I need to contact Mack to buy a manual? Thanks again

Thanks for the quick replies. I'm hopeful it's not an injector. I'll unplug the timing control off the injector pump tomorrow morning and determine if that makes a difference. Appreciate the help! Nate

Anyone have any thoughts on this? I'm ok with some general places to start. Fuel filters are new. I haven't checked the fuel check valve but uncertain if it would exhibit these symptoms. Thanks!

New to the forum! I just bought a 98 Mack Midliner 24' box truck last week and am trying to work the bugs out. We use it for hauling floor tile-it works great with the 5,500# Maxon liftgate! It's a great driving/running truck with 140k on it-still getting used to the turning radius with the rear tandem down but otherwise great. This of course has the Renault engine. The main issue is a startup. It will crank but not start unless you tap the accelerator a few times while cranking. Once started it will stumble and buck for 5-10 seconds then cleans up. It blows white smoke (fuel) while cranking until it reaches standard idle. Power is fine, or as good as 210 hp with a 6 speed can be! No coolant loss or oil consumption. I'm anticipating the answer is in the fuel rack or a sensor. I can live with it for now but anticipate as the temps drop, I won't be able to get it to light in the winter months. Any insight is greatly appreciated. Thanks all!