JoeH

Our shop compressor airs up to 150psi, shuts off, then kicks on again at like 115 psi. When you get down near 115 it takes a while to trigger it to pump back to 150. Tires hold a lot of volume. And if you're working in flat mud, you're not really winding your turbo like you can on hills...

Don't change the coolant filter too often. They're supposed to have an additive in them to revitalize your coolants pH level. Changing too often will skew the pH level in a bad direction.

Haven't looked at the hood in a while, don't recall if it's really even usable. Scoop is fine, I can just cut the hood around it and let you separate them. Whereabouts are you? Haven't thought much about boxing it for shipping.

Cat motor, no thanks. Looking at that interior, I'd believe the mileage. Talked to an oil customer today who drives a fuel truck for h&k, he guesses my '88 we just bought is probably around 800k miles. Mine has mold on the dash around the cup holder screwed to the dash panel, HVAC duct work is duct taped, dash panels are not secured well... Radio missing from the overhead... That super liner probably hauled a low boy to and from job sites. Less trips than a dump truck per day...

We just bought an h&k Mack from Coopersburg kw. My dad bought his first Mack from Bobby Metzger there in 1987. Still running it. Truck we just bought had new frame rails and trunion put in sometime in the past 5 years or so, and a good ticking motor. Mack Macungie plant gave their construction work to another construction company, so h&k traded 60 Macks in for KWs. Or so we were told... Some of those triaxles are in really rough shape, some aren't too bad. Coopersburg had the lift axle off one triaxle, bottom frame flange was rusted clean through... We only put 5-10k miles a year on a truck, so we'll get 20 plus years out of our purchase as long as Volvo doesnt screw with parts availability too much more...

I've got a hood with a scoop on it from a 1981 Canadian r686st. Hood has some cracks, but the scoop is in good shape. Don't have anything else from the truck it went to the junk yard close to 10 years ago. Thought I'd offer it before I get around to cutting it up this spring. Can try to upload pictures if anyone is interested. Southeastern PA.

We just bought a 1988 triaxle with an em6-300L / t2070 maxitorque. How does it compare to the endt676 285 hp / 2 stick maxitorque? Not sure what ratios it has, does 60 mph at 1600rpm on 24.5 rubber. Is the em6-300L a maxidyne? We're rehabbing a body to go on it, so it'll be a few months until I can compare to our other trucks! Hopefully it'll have more scoot than our 95 mechanical e7 350...

Great advice on sandblasting in the cold! If you have the ability, chill your garage before bringing the blasted parts in. Once the parts hit room temp then turn the heat up? Glad to see someone saving a good cab! Most of my R models have rust holes along the back of the roof! Doesn't help that we use muriatic acid to wash them, it's about the only thing that takes cement off....

We use waste oil; it's dirty and horrible to deal with but it's free! We have a local shop that gets us about 750+ gallons a year! Our tank for the heater has about 4 inches of sediment in it from over the years.... Can't wait to replace the tank and deal with that mess!

My 95 rd takes forever to air up, but it's a triaxle so it has extra tanks. The compressor gets air from the turbo, so it may be a low cfm pump that relies on turbo boost to be high cfm. How are your Pete and Sterling set up for compressor intake?

As swishy said, "self" adjuster gets so far out that S cam goes over center, effectively releasing that brake, giving you unsynchronized brakes. This is why i always liked manual adjusters, you gotta get out and set them, and the truck will stop straight every time. Added bonus is while youre in there you gotta look at things like brake linings, air hoses, springs, youll hear if a maxi is leaking, etc. Downside is if you hire incompetent people that won't check them then they'll rear end someone at some point.

+1 on the rust, gotta disassemble frame, sandblast and paint before it gets to cracking point. You could probably still take it apart and weld it back together if it's the horizontal flange crack by the trunion. Mack frames want 100,000 pound tensile welding rods, 3/32nds for frame repair. I think 10018 rod? Took my dad and I about a week and a bit to do our 95 rd. Well worth it, but we didn't have any cracks yet. Because the DOT caught you you might have to show them the truck to be put back on the road, or sign that it's been fixed. Once it's been welded, bring it so you can't tell it's been welded.

I have several seized anchor pins on my trucks, never get this. When I drive other people's trucks I do sometimes. Adjusting the "self" adjusting slack adjusters takes it away for me...

Ratio should be stamped in the carrier housing on the differential housing. Axle ratio is how many times the driveshaft has to spin per wheel rotation. If the ratios are different, youre going to blow up one of the rears. If they're the same, check your driveshaft for bad u-koints or a bad carrier bearing. (Rubber bushing looking thing to hold it over the lift axle) Power divider is a switch on the top of your dash. It forces one wheel on each drive axle to have to spin. (If it's unlocked in mud, all it takes is one drive tire to spin and you lose all power through that wheel) Never switch it when a wheel is spinning. Never drive on blacktop with it locked. If all else fails get an experienced trucker to ride along with you.

You can get pneumatic cylinders online for cheap, just need to measure the throw and figure out how to attach it to the butterfly valve.

My 95 RD e7 350 has a "cold start only" switch on the dash, operates some sort of intake plumbing that bypasses the intercooler until things get warmed up... We have never had to work on the engine in the 10 years we have owned it, so not real familiar with it. And we never use the switch b/c it's in a heated garage....

Glad it's not you that's in for the never ending repair bills then! My dad and I are picking up a 1988 rd6882 tri axle with a new frame (guessing 5 years old) new camelback (5 years again...) rebuilt rears (5 years...) a rebuilt 300 horse with a T2070! About the only thing wrong with the truck is duct taped hvac, some mold on the dash, and it's the wrong color. Price? $21k! Thats how you buy a truck. 😉

Your problem is you bought a new truck! You're supposed to buy em after someone else figured this crap out.

I can't see that in the pics, but I'll take your word for it!

Double frame looks in good shape, can't see an oil pan to see if there's even an engine in it. Hood has a nice crack, nothing a 2x4 fiberglassed in can't hold. Doesn't look like there's a rear window in it. Needs a lot of small stuff though... Maybe worth 1500...

The 2001 rd688st I owned for a year had relays in the glove box and a relay/fuse box under the hood, top center on the firewall. It had an etech 400 engine. FJH and co. might be talking about the accessory relay in the dash under the ash tray. On our mechanical Macks, when you bump your key on it actuates an accessory solenoid in the dash under the ash tray. It powers your gauges, radio, blower, etc. Not sure if the electronic engines use this solenoid too, I expect they do. The last couple I got from Mack are junk, they get hot on our stock truck and stop making contact reliably. Smack it with a screw driver handle usually gets it to engage.

Build sheet says "extra roomy cab interior" What are they comparing cab roominess to? A Mini Cooper? Never worked on an E9, are they shorter than an E6? Can't imagine them being much shorter, your only 4 1/2 pistons deep instead of 6... Maybe that's the "extra roomy cab interior" - less dogbox.

Made me think of Maxwell the Pig.

+1 on the engine brake. It'll make a big difference. 1) cuts shift time to less than half, and 2) Jake keeps the turbo spooled up a bit. I would try that before swapping transmissions. Makes the maxidyne & maxitorque a real heal climber. 3) when you use Jake to slow down through your curve it can keep your turbo at 10psi boost if your RPMs are kept at1800+ for long enough. Note his problem isn't low end, it's 40+ mph.

Those are sweet dimensions. Do you have those drawings for a 1995 rd688s? 228" wheelbase? Does Canadian spread tandem have the same turning radius as the closer set American tandem with same wheelbase?