mechohaulic

At one of the fleets I worked for, I took a quart of AIR LINE alcohol (not from a package store) :drained the wet tank and pour the quart in. with marker wrote date on the tank. tanks were orange = black marker showed easily. every month drained did process over again. this was done yr round. never had a problem with frozen brakes in winter either. the alcohol kept system clean, many people wait till cold weather to add alcohol. this loosens all the crud sends it through lines. union company== drivers never drained tanks. far as this unit; i would suggest the airline alcohol treatment ; the alcohol will mix with the water /oil make it easy to drain till it's clean. as above stated, regular drain is best. starts showing up in other tank or goes brown to black that's raw oil not condensation .

I didn't think the rear mounts had that many variations . have mounted a few but that was years ago .as with everything else back then no one paid much attention to keeping numbers or all the stuff would be collectable 40-50 yrs later.

nice picture of "open air shop" ; sure brings back bad memories for me seeing a R-model on trailer. after loading a R-model on non-detachable lowbed and being in a major hurry;; stepped out of R model forgetting i just loaded it ; stepped out to a long way to ground level! one of many reasons my knees are past worn out.

sorry for correction '' not"he was part of the greatest generation . He IS part of the greatest generation.

the "greatest generation" is slowly passing away. with their passing goes knowledge and stories that will never be duplicated. I've been so fortunate to know a number of them. short story never forgotten by one of my mentors was how He took an AC chain drive Mack with well rig on the back from CT to Maine for a job. trip was three (3) days ride EACH way. LOL and the Mack was near new at the time. must be due to fact he didn't have his usb plug🤣

another thought to having a full crew is 1- more projects can be worked on at the same time ;2- faster doesn't need to be part of restoration ;3- quality has a better chance. many positive comments have been made through out this B73 build. for basically one individual to have been responsible for the entire 73 build and have it come out beyond perfection ;; no one sentence can sum up how great it looks.

seems there 's more progress on the real trucks of these forums then i can put into the 1/25 scale projects i have on hold. don't know where the time/ days are going. now i have a '84 john deere apart trying to find clutch parts; grass is still growing; etc and the list gets longer daily.

kinda late now but i always use lighter fluid made for the out door grills , spray the wood let it soak then light the top wood. it gets going slow burns in the wood . as above mentioned ; thoughts and Prayers for fast recovery.

quick look it seems like 4 wreckers set to retrieve the load. study closer 'it's 3 white wreckers and what looks like a 4th blue wrecker is actually the rear section of trailer. or I really do need new glasses...

don't feel bad about the laugh; i got basically the same reaction going to a john deere dealer and asked for a clutch assy for a 1984 JD 1450 i have apart right now. things are definitely different in today's world . that brake switch should be the same in later yr vehicles also. 1/4 or 3/8th pipe square top with two Philips head screws . unless it's totaled ;take it apart and emery the brass contact plate inside.

glad I'm not the only one with that thought . LOL .

one thing to keep in mind, much like the emergency shut off on the DD's ;; it called emergency for a reason. too many times of use it will suck in the seals on a turbo. engine at over high speed wants air from some where till it starves. a pair of vise grips flatting out the fuel supply line in some cases will be faster than taking off the intake hose to access the intake, NOT saying the flat piece is wrong;; anything to shut down a run away fastest .in total agreement regards to the plunger being the cause.

my number one priority would be to jam a rag in that drain hole to stop metal contamination going further in the oil system.

broken /weak spring in oil pad high pressure over ride, engine won't know it gauge and electronics will

if you are going to replumb this trailer with intent of running the road , law might say it must be done by todays standards meaning has to have spring brake parking brake. in that case clearance can be a situation requiring 24/24 cans . use to need two separate valves (R-8?R-6). modern technology must have a dual system valve set up; that can be effective yet simple for install. i wouldn't be concerned as to what it had but what will you need that will be safe and up to standards. good air tank, combo valve to screw directly in tank, 4 maxi cans or 2 maxi and 2 plain service cans . don't think anyone bothers with hose length vs hose size. should be 1/2 dia hose.

the old style trailer brake systems did NOT have maxi ( mechanical spring ) brakes . the single diaphragm can acted as a service brake and ALSO a parking brake. the magic was the valve it self. the valve screwed directly into the tank. brake application service side == air was directed through valve to brake cans. when disconnecting from trailer the brake valve closed an internal port and opened another sending air to the cans to hold brakes. imagine some little munchkin in the valve holding his foot on the port to keep air pressure going to cans, when the system lost it's air, "parking brake " was no more; resulting in trailers rolling away when fifth wheel backed under and landing gear came off the ground. that was the reason for the ridiculous procedure of back up to the trailer not touching the fifth wheel to trailer;; get out hook the hoses= charge the air system then apply trailer parking brake == then back under. even after the maxi can spring brake can was mandatory ; D O T inspectors made you follow the rule of the '40's/50'swhen going for CDL test.

thanks right back to you for the latest update.it does become frustrating when questions are answered by many on this forum and the "questioner" just vanishes from the planet, LOL .

do you have an air dryer that hasn't had the filter changed restricting air flow ??? being a '70 doesn't mean someone hasn't "modified" things through the yrs . has this issue been there or just become noticeable ??

when you say " all 4 segments drop the same" , does this unit have dual air system ( red and green needle on gauge);i don't remember when that started. when dump body was installed, were the air tanks moved or replaced? the main wet tank has a check valve connecting other half of tank;; when gauges are at 130 if you open each drain on the tanks individually ; does each drain have full pressure of air coming out ? have seen the one way check limit air to other tank half. tank not having an external check has one internal , pain in a-- to change, AFTER draining tank remove fitting on end of tank flashlight can see the internal check, long extention and grease on the socket will remove the check. have also seen an improper discharge line from compressor become restricted from wrong line too close to high heat compressor air. also as you stated ;;yes older units weren't made to build air like todays iron ;; NOT counting fire apparatus ; they had a rapid build up system.

what are you running for a signal light switch? old square original box or has it been updated ?

how many wires running to the back tail lights ?? rear turn signals on tractors didn't come to be till later yrs. were they working= now don't ?? brake switch is air operated .. front signals working ?? B61 tractor or straight truck.if it's tractor, are brake lights working in light plug ?

So when the Mack museum calls and makes You an amazing offer ; will you be able to say -yes or no. with out a doubt all Your effort has paid off and You have built an above museum quaility show piece.

depending on how the term "longest serving " title is meant, i know the R -model fire truck i delivered while working at waterbury mack in CT to winchester center back in '71 is still there may only be for parades or major emergencies . CT has (had) a ruling a fire apparatus can only remain front line equipt for 20 yrs. many times after the 20 yrs a unit is sold/ donated to another dept.

you didn't circle the difference of the one dot vs two dot in the trees under the big red circle of the trees and the air intake difference circled in red.

sounds like my marriage==first look -not bad; start pokin , moving "stuff "around ;; then the issues start add😁ing up 🤣, once again couldn't help myself LOL