Rob

The full flow is physically larger in length and has three hoses out of the bottom. One of the hoses is considerably smaller than the other two. Also I believe all the full flow filtered engines used an external oil cooler on the left side of the engine. Rob

I know the experts here at BMT wouldn't steer me wrong so I ask as to avoid making mistakes. Rob

Sooooo, do you all think if I was to install my 11.00X20 tires on the road side of the drives, and my 9.00X20 tires on the curb side, I could stike me a deal with either M&M Mars, or Hershey's for making peanut butter with my Mack power divider? I do have a few 7.50X20 tires which could be used for a "finer grind" if need be but don't have the correct spacers for them. I could market the idea such as: Rare Earth Mineral Candy. So, good proposition or what????? Rob

Good on ya. Rob

Base oil stocks are the same and originate in the ground essentially. Refineries add different compounds and chemicals to formulate a final product to meet certain specifications and criteria. These differing compounds or formulations can easily conflict with one another and when brands are changed strange things can happen. Remember the standard warning on wheel bearing greases? They still print to not intermix types due to incompatibility. This is due to the "soaps" used to thicken the oil which comprise a grease not readily intermixing with one another and a point of starvation can occur. It is not near as prevelant as in years past but still a possibility today. Nor is engine oil faced with the same incompatibility issues. However diesel engine oil is much higher in quality than it's gasoline rated only counterpart to keep byproducts in suspension better, and with increased shear strength of the film a diesel engine is faced with. This is why gasoline rated engine oil always starts with an "S" rating, where diesel oil is rated with a starting "C" rating to distinguish between the two. I don't know how that rating system came to be however. I suspect an incompatibilty between sealing surfaces which had taken a final set against one product in your trucks lifetime, was aggravated when the switch was made to Rotella causing your aforementioned problems. Rob

The guy that gave me my B67 called last evening saying his blower in a 1988 R model quit working. He replaced the blower motor under the dash to no avail so he's wondering if the switch is bad? I don't know if that truck has a variable resistor pack in the air plenum or not so I'll ask here before advising any further. Most cars do not limit the running current or voltage through the dash switch any longer and I don't know if the trucks of that vintage do or not. I'm T/S over the phone right now but he'll bring the truck to the shop if need be. I don't know for sure what series of truck it is but it's a standard R model with an E6-350 so probably along the lines of an R688. Does anybody know for sure if there is a resistor pack in the air plenum? Thanks, Rob

Whether divine intervention played a role or not that is good news. I've never used Rotella oil but rather Delo, or Chevron in all my diesels. I really don't have anything negative to say about Shell, or it's products, as there are far too many users out there that swear by one product or another. My local distributor is a Mobil, and Chevron, Texaco, Castrol dealer so I stay with his products on top of good performance. Rob

Those "rookie sticks" are solid 1.25" cold roll steel with a 1.25" solid ball welded to the top, they are as tough as the rest of the truck. Matter of fact the truck was built in Marion, IL. Rob

I had them on my R795 but removed them, epoxied the holes shut and finish glassed the balance. I think they are a good idea when driving in traffic but I don't favor the looks of them myself. I do like spot mirrors on the lower portion of the door mirrors though. Rob

I can only assume he washed his, and others' feet before performing the miracle first. Rob

Looks like he had a good sense of humor. Gets you through sometimes. Rob

But will he perform miracles? Rob

Hi Bigen, I was not referring to your truck. I had to go back to the initial post to see what you meant by "mirrors on the fenders". I was referring to the 2009 truck on truckpaper. Sorry for the confusion. Rob

If it idles smooth and steady, I'd suggest changing out the throttle arm on the side of the injection pump, and looking for loose connections in the throttle linkage as a start before moving to the governor internals. Rob

Those doors should be positive in latch engagement and not rattle in the door opening at all. Good perimeter gaskets are paramount for this to happen. They are inexpensive too. If Macks thinks there is "nothing worse than a rattly door", then he's never had a scorned 230 pound butcher knife wielding woman that knows where he sleeps as I have!!!! Rob

Hi Herb, the only snap together one I've been exposed to had loosened and wollered the ears that fit together and was really loose. It gave the truck a metalic "ping" at idle that was difficult to find. Rob

Is the airflow discharge rate from the vents deteriorated from the past, or is the discharge air not a cold as it was? A clogged evaporator usually restricts the airflow through the coil and the discharge air drops in temperature due to the airflow not removing temperature within the coil. If your airflow is satisfactory, you are either low on refrigerant charge, or have a mechanical problem. Ensure your condensor is clean in front of the radiator to allow proper head pressure during operation. Rob

The "E" is for exhaust. The line terminates into free space under the truck cab. It does not connect to anything. Cheap insurance is to rebuild that "Selectair" valve while you have the truck down. Parts are less than $20.00 from Mack. Rob

You too have a blow up doll???????? Rob

It's a nice truck that is borderline "gawdy" with all the brightwork installed. Rob

Ask Other Dog to deflate his so you can borrow her........ She don't say much. Rob

The B model emblem is taller, and wider. I looked for years for a replacement for my 51 A40 and finally ran across one. Is yours missing, or dented up? Rob

My limited experience is that I like the "screw together" type rather than the clip type. I've seen the clip type work loose and rattle. I've also seen two types of screw together types. One used recessed Allen head fasteners, the other flat headed screwdriver type fasteners. The Allen head type was more compact but would be difficult to install and tighten without extended reach wrenches. The flat screwdriver type would only require a long #2 straight slot screwdriver. Rob

Sounds like the electrical connections behind the horn button located within the steering wheel are needing adjustment. I'm assuming the horns are electrically actuated and slaved to the horn relay under the dashboard. I've seen this several times through the years with the electric horns but have never dealt with an electrically actuated air horn setup. The theory however, is the same. Rob

Here are some photos of my trucks in the areas we have discussed: The red solid color truck is a 1978 RL755LST series. The brown truck is a 1974 RL797LST series. The red truck that has a sanded hood is the 1977 R795 series. Plus a few other miscilaneous photos cause nothing better to do. You can see the differences between them, and the lower fender/battery box arrangements. Also the hood on the 1978 RL with the body character lines. I even moved the brown truck to allow the opening of the red truck's hood to show the serial paint markered on the underside. Rob