Rob

I was worried for a short bit there till reading the disclaimer. Rob

I don't smoke, dip, drink, wash or wax anything including myself and am constantly flat broke. Suppose I do have my vices however to the tune of 10 Mack trucks when my livelihood has absolutely nothing to do with trucking. Fortunate for us all it is widely recognized that Mack trucks are not a frivilous expense, but rather a necessity for sanity and enhanced quality of life. Rob

I have found it much easier to pull the pump complete and send it in as opposed to remove the governor from the pump while on the engine. The pump can be evaluated properly by the fuel shop when rebuilding the governor also. Rob

I had the flat bulldog mirrors on both of my Midliner carriers. I liked them because they were heated. That was about the only reason however. They oxidized and did not look "new" for very long operating in the Chicago atmosphere during winter. My 1989 Midliner came with painted bubble back mirrors and arms. I changed to the stainless and bulldog mirrors. I still have the originals in the basement. Never had any problems with vibration as those trucks really were smooth in operation. Rob

That's great to know as I prefer the old bubble back ones myself. Although this truck was always a Texas truck and never seen any salt, the 1/2 bulldog mirror is oxidized with the dog pitted. I have a new pair of both styles so will install the bubble back ones. This truck is very "fleet spec" with no real amenities except factory air conditioning, and power steering. Thanks, Rob

That was a perfectly good Mack five speed that went down the hole. I can replace the goat without fanfare next spring just before the grass starts to grow. That hole's purty deep too. I warn against jumping down it cause you're libel to wind up landing in some Chinese manufacturing facilty producing products for the US market as prison labor. Rob

Thanks Herb, I knew they were new about that timeframe but certainly didn't know for sure. Rob

On my 1980 Mack truck there is mounted one stainless bubble back mirror, and one stainless type with the 1/2 bulldog, and inside the cab a flat back generic looking style. I don't know which is correct for the truck. I have "spares" of both types mounted on the truck. The mirror arms are stainless. Which style is original to the truck? Thanks, Rob

None of my B models have the rubber insulators. Rob

Well tonight I removed the factory underdash HVAC unit after putting power to it. The fan runs on all speeds and will probably be installed into the 74 RL complete. This truck had a "Kysor" roof mount unit that was no good and missing parts. The 866 engine however still has the junk compressor mounted, (Sanden from the looks of it) installed so 1/2 the battle is over from the start. I'm not going back to a roof air unit but rather will install a front mount condensor coil and quite possibly use this underdash unit. I did discover the cab is either a 1989, or 1990 model as most of the plastic air lines are date coded 1989. Too bad this cab sat exposed without doors for some time as it had the upgraded interior package that was destroyed partially from exposure. Rob

Is your compressor a rotary screw type, or reciprocating? Screw types make a lot of compressed air in a small package but really generate a lot of water in comparison to reciprocating piston type. I can't stress enough to drain the traps frequently. Cleaning out a high flow blaster hose and fittings for a steady and even spray can be "entertaining" if the ancillary equipment service is neglected. Rob

I have a "Brute" 150# pressurized pot blaster that works very well. Really don't have use for one much larger. The pot is not the important part but rather the moisture traps/filters are the leading indicators. You don't need water in the sand as it will clog and restrict delivery of the material. Do change your filter media often and drain the traps several times per day. Stop by any vendor that supplies "Sullair" brand compressors, they will steer you correctly. Rob

I believe the oil galleries within the block are cast and bored differently. Rob

I always ran a plastic disc with my camper. I did grease the king pin itself because it does pull and twist in the fith wheel jaws. I did not grease the platter on either the camper, or fifth wheel side. Rob

There is a guy around here that runs a "CL" series tractor and the hood dog fits inside a custom doghouse he built. The house is welded, polished stainless steel and really does look good. Rob

Yes, but then they come to the realization of how much GOLD could be traded for just one of those cabs and switched to another brand for the sacrifice. Can you guess which red oval truck is in high demand for this operation now? Rob

The valve is relieving at 155psi by the gauge I've installed into the tank. I removed the drain cock installed the gauge into the port. I agree with Glenn as it takes air pressure to raise the pistons in the compressor head. If the rings are passing air the pistons cannot lift thus the compressor will not unload, or send air to atmosphere but rather to tank. The dual needles of the air pressure gauge in the dash will peg against the "0" stop after wrapping completely around the face. Rob

Great news and congratulations! It still is a lot of work I know but will be worth the effort when complete. Rob

Hi Glenn, I have a few Schrader valves with 1/8th NPT threads and will do as you suggest. The line from the receiver to the governor is connected and routed properly without restrictions. The governor does pass air pressure to the unloader port when it's setting is reached. I suspect the unloader pistons are leaking by their respective "O" ring seals as suggested. I don't think this is a Bendix compressor as the unloader port is a bolt on type plate with three capscrews retaining it to the head. It uses a #4 Stratoflex hose connected to the unloader port. Thanks, Rob

There's all kinds of good parts on that truck. Even if the engine is junk the intercooler, turbocharger, power steering gear, front brake axle, etc. are desired to the restorer. Most Most Mack tractors of that vintage had a nine inch frame and they served well. I always thought the five spoke rears were 34,000# rears but I've been corrected as they very well could be 38.000#, or 34,000#. On the rear rear banjo housing to the right of centerline will be a stamped number. That number can be decoded to what the suspension is rated at. When you finish with the parts you need please do part the remainder fairly starting on this site. I don't personally need anything at the moment but somebody does. Rob

This R612 is making lots of air pressure, to the tune of blowing the relief valve on the tank. I adjusted the governor with no luck, so I replaced it with a fresh reman unit. It will still make air with all settings until the relief valve on the tank opens. I disconnected the unloader line from the governor that runs to the compressor head and it unloads as it should, according to the adjustment screw setting. I'm thinking the unloader valves in the compressor head are not functioning. Has anyone seen this happen before? The air compressor seemed to work fine a couple of days ago. Rob

I did not make it. Been chasing & replacing burnt wiring in a 62 year old radar for over two weeks. Have extra help coming in from Detroit tomorrow. Both of my codrivers opted out for the Lititz trip and it was too far to travel solo to be back Monday. Really need to get this problem here at work fixed. Rob

Tonight I sacrificed a cab for the good of three others. I purchased this badly rusted cab someone had patched/repaired with a new roof skin and rear drip rail, (gutter). It appears the truck was then run for awhile, and clipped in the cowl with an end loader bucket, destroying it. With both my 74RL797L, and my 77 R795 needing sheet metal work in the roof and rear gutter areas, I used a five inch, 3/32 cutoff wheel and took the roof off the cab just under the drip rail. Pretty clean job that way. Tomorrow I'll strip out the inner sheet metal that is not needed by drilling spotwelds and get this skin installed onto the 74 truck. The gutter will be installed onto the 77 truck although I have new parts. This 74 truck is not a long way along so it can go back in a corner till spring under cover. I'm wanting to concentrate on "Project R-12" this winter, and need the room this truck, and the associated parts are taking up. The relatively new windshields, with gasket were removed and will be installed into the new R612 as both are cracked. The PP1 valve now also resides in the R612, and this solved the air leak problem within the dash. Also the dash panel was appropriated to replace the missing original. Rob

That's great news!! I know the excitement well after reviving something that has been setting for a long spell. You really want the experience to be positive, and am so surprised when it is easily attained. Have fun with it. Rob