Mackpro

Saw this on an old CH I was working on today.

It's a whole lot better to have oil running out of the engine ECM than antifreeze. The ASET's sometimes have the low coolant sensor leak antifreeze into the harness and it will make its way to the engine ECM and rot out the pins in the ECM. The MP engines usually have the oil level/temp sensor leak oil into the harness and usually not hurt anything but make a mess(sometimes cause weird codes to appear). So as long as it's just oil were are OK. Oil pressure or oil temp sensor is probably pushing the oil into the harness, we will get it figured out.

I'll make sure I have a switch and go ahead and try a new cap, just make sure it's a 16 pound cap. This cooler weather is causing lot of cold water leaks.

If you have a truck down with the bad cups, get the new style stainless steel cups and new style injectors. We have put several sets in. However today I had to pull a stainless cup out and replace it. The new cup didnt fail but the injector hold down bolt broke and the injector jumped around and damaged the cup.

We got the thermostat kit for $101. Yours is probably orignal and they were prone to leaking, as Rasler said these new style have a better o-ring for sealing.

You do have a Wabco compresssor and a Bendix AD9 air dryer on your truck. The Wabco compressors did have problems with their valves getting gummed up with carbon/sludge but this usually caused the compressor not to build up air or build up slowly. We had alot of Pilgiram Pride chicken trucks have this problem and had to replace the compressor head with a new updated head. Although I never remember it affecting the air dryer operation.

It does it have a MP engine? If so, it might be low fuel pressure due to blown injector cups. There is finally a fix for this as we have been putting in the new stainless steel cup's and new style injectors. Is the truck model a CV713 or a GU713?

Call Rochester Fuel they list performance CCRS injectors which are the same injector body as the AI injectors. I have talked to them before and they were very kowledgeable. http://www.rochesterfuel.com/products/etech-ccrs-stage-performance-injectorexchange-p-200.html

Thats what our DSM is also saying. The only problem I'm hearing is the DEF pump but Mack already has thoses in Reman.

We sold our 1st SCR truck today. It wasnt on the lot for a week. The guy took a test drive and the 505 HP made the sale easy. Started putting on the PTO and extra chrome this afternoon. Our sleeper truck CHU 505HP will be here any day, it was a custom order and is of course sold.

We have lots of 08+ MRU's running around here. Very few LEU though. I think I have a MRU to work on in the morning as we speak!

On some trucks (depending on software level in the engine ECM) the dealer can go in to the Engine parameters and uncheck the "air conditioning installed" . This way the Engine ECM ingnores the signal from the A/C high pressure switch and the fan should stay off if the problem lies with the A/C switch. However the 1999 CX I was working didnt have this feature but most newer trucks (2002 I think) do. The dealer should be able to use the laptop to check whats going on unless it is a bad Engine ECM. Does you dash have the fan override switch on it? If your truck has the APADS A/C system this could be the main problem. The APADS is a small square electrical box/ECM that is bolted near the radiator and has flashing lights to tell you the A/C is not working. The wiring on the APADS is so screwey that we always remove them and throw them away.

had a 1999 Etech in a CX today and the Horton air fan was coming on and off constantly. The water temp was only 180 degrees and the A/C was turned off. Hooked up the laptop and went to "switch status" and could see the A/C pressure coming on then off and the "Fan engage" was doing the same, this will happen even if the A/C is not turned on. Turns out it was a bad A/C high pressure switch. I also looked at the coolant temp and intake manifold temp on the laptop as if these get to high it will also engage the fan. Fuse 41 sends 12 volts to the fan solinoid the it returns back to the Engine ECM where the Engine ECM will ground the return wire. Basicly the Engine ECM makes or breaks the ground to control the fan clutch. It can be a pain to figure out without the laptop and Mack software.

Next time your in I'll turn it on where the fan will engage with the engine brake it helps. In the summer when going slow in very hot weather the A/C will kick on the fan clutch for 1 minute when the A/C head pressure reaches 300psi. I sometimes turn this down to 30 seconds if the truck is in dusty or farm field conditions so not to kick up as much debris. I cant remember what kind of fan clutch you have, I will look it up in the morning, I assume it a air operated Horton. If it has the Behr Electric Viscus fan there is no programing that can be done to it and you cant add a over ride switch on the dash. I got your cab shocks and air drier filter hid out so it will be here when you come by. The man up north working on the EGR bypass is waiting for me to send him some connectors but I have been covered up here at the shop for 2 weeks solid and I havent had a chance to talk to him.

On the Mack SCR website, somewhere on there it does talk about the DEF/urea being a byproduct of natural gas and that the price of natural gas will determine the cost of DEF. Our dealership has some onhand and also our local Ford car dealership has it instock all well (dont know why?).Our 2011 SCR trucks that we ordered are starting to show up now. All we have ordered is CHU's with 505HP MP8's.

I talked to a ABF driver that delivers and picks up at our shop and have gotten to know him over the years. He didn't know anything about the big buy. The first thing he said is "How can ABF afford this, they keep telling us were broke". He has 3 years left till retirement and ABF just closed our local treminal. Now he has to drive more than 75 miles one way to work for the next 3 years. He wasn't to happy. I do all the Mack warranty at our shop and for years we always returned the large warranty items back to Mack via ABF. Well about 2 years ago Mack said dont use ABF anymore. Appartley Vitran bought more new Macks or Volvos than ABF did and now we have to use Vitran and our second choice is Yellow Freight. Hopefully with this new ABF purchase we can go back to shipping with them.

It's on the back side of the coolant surge tank (where the metal radiator cap is/ top tank)

This has been done. It helps if the dealer you bought it from is also the dealer that has been repairing the problems. They need to get the DSM (distric service manager) involved and if he doesn't seem willing to help then time to start calling corprate headquarters. I will say this, we have customers who are used to older RD's and CV's that have very few breakdowns ( 1 breakdown/engine repair every 2 years) and then get into the GU's it' s whole different ballgame with breakdowns. Not that their bad trucks, but the techs working on them are used to very simple "Mack" engines and electronics. It's like working on 5HP Briggs and Stratton lawn mower engines all your life and then they make you start working on 2011 Corvette engines, sure it's still a engine but a whole different animal we have to learn. We at our shop have seemed to figured out most common problems with the MP engines and DPF's and of course now we have to deal with 2010 emissions and urea injection/SCR. Due to the EPA we are always having to change something or add something to the engine. It's not just Mack thats having problems, everyone else is too. Sorry to get somewhat off topic but here latley I have seen Mack take in 3 2008 CHU's on some special trade deal due to constant engine problems and replace them with 3 2011 CHU's with SCR engines. Dont know the details but the customer was very upset with Mack over the 2008 engine problems but did the trade anyway so it must have been a great deal.

The only time both "Red X shutdown" light and "yellow lighting bolt EML" come on at the same is when there is a low coolant fault. ( except on the DPF equipped MP7 and MP8 engines)Check the coolant level and if it's full it could be a coolant level sensor failure.

Best I remember and it's been 15 years ago, I used a small long chisle to make a screwdriver slot in the top of the bolt and then use a screw driver bit in a 1/4" ratchet to remove it. One time I cut the heads off with a dremel cant really remember how I got the dremel in there though? I then went to Lowes/Home Depot and replaced the screws/bolts with allen headed screws. I remember doing the Robert Bosch pumps that way all the time. The AMBAC's were nearly the same.

What really pi##ed me off was when Volvo changed the street adress of the Mack Warranty Parts Return Center (TMAC) from Macktruck Road to Volvo Way. Yes they actually changed the name of the road. What a slap in the face!

In the pic "cooling1" part#26 is the screen, in the pic "cooling2" it's also at part#26. Mack says for regular antifreez (not extended-life) change every 2 years or 200,000 miles.