Doffer

Okay, thanks for the information!

I have been running a 2003 Mack MR688S the past month or so since the windmill jobs have been done, and I'm having some issues with my truck I was hoping you guys could point me in the right direction. I remember before I posted a topic about the 1994 Mack MR688S I was running and asked about the oil pressure, and you guys said that it was OK being where it was. Now on the 2003, the oil pressure is running when the engine is hot below 30 PSi at idle. Is this Okay? Also, sometimes when driving up hills the turbo sounds like it stops spooling as fast as normal. I actually loose speed because the turbo quits working. I do not notice any smoke, and the engine RPM are usually steady between 1600 - 1800 RPM. What would cause the turbo to do this? Finally, every once in a while my truck takes forever to start up, It usually happens when the engine is hot, but i've had it happen when its completely cold as well. I actually recorded a video and from the overall length it took about 6 seconds of constant cranking for it to start. I know these have the plastic bosche fuel pumps, do you think the pump could be getting weak and loosing the prime?? That would make sense to me, but it doesnt have any problems Revving up to while operating on the job, which kind of is throwing me off because when I had a fuel pump go bad, it started to sputter real bad, and this truck once it starts doesnt skip a beat besides the turbo while driving engine hours are 13565.3, 133133 miles when i fueled up today heres a video of it starting: I really appreciate the help / comments so far, and would appreciate some help on the few issues im having currently. Thanks, Brandon

They are about 700 yards of concrete in each base!

Havent been logged on here in a while. I've been up in Ellenburg NY pouring concrete bases for windmills for the past 2-3 months! Anyways, Ive been running a 2004 Mack MR688S Cabover. This thing is a SWEET ride. the only problem I had the whole time I was there, was the fuel pump took a crap. For anyone who hasn't delt with the fuel delivery pumps on the 2004 mack, it is a good idea to keep a spare on-hand since the entire pump is made out of plastic besides the center shaft which is steel. Even the gear is plastic! For more info on the wind farm, check out http://www.noblepower.com/our-windparks/ellenburg/index.html

on the booms, its recommended to change the boom system every 10,000 yards. The cups need replaced around that also. The cups are the large Rubber Plungers attached to long hydrualic cylinders that push the concrete through the boom-line. The boom line on the larger pumps is a smaller diameter, so it wears a lot faster and its right around 4,000-6,000. These numbers are just recommended specs per manufacturers. A more realistic number for the smaller booms is around 15,000-20,000 yards before it needs replaced The hopper, and the pumping components are all Hardfaced, so the parts last a longer period of time. The boom system is not hard faced though, so it tends to wear out quite quickly. Not sure what the Yardage to Hours would be

Well that is good news indeed then! I just recently started running this truck, so i wasnt sure what the normal pressures were. On my other Mack, the oil pressure is higher, thats just why i was worried. Heres a few pictures of her

I run a 1994 Mack Truck with a Schwing Concrete Pump mounted on it. I am wondering what the normal oil pressure is supposed to be, HOT while idling. currently its hovering right around 30PSI which seems too low to me. When cold its at or above 60Psi, but as it warms up it gradually gets lower. If i am throttling the truck, the oil pressure is OK. The engine has 21750 hours on it and it has 550,000 miles on the chassis. The Engine Brake works great all the time if that helps? Any input would be greatly appreciated.