HK Trucking

That was the Eaton 3 speed tandem axle setup you're referring to. 1 was both axles in low, 2 was 1 axle in low and 1 axle in hi, and 3 was both axles in high. Those used a conventional spider gear type inter axle power divider though, and not the cam & wedge type power divider like the Mack tandems. A spider gear type power divider will not clunk or bang if there is a difference in axle ratios or tire sizes the way a cam & wedge type power divider will. That's why with "brand X" tandem setups you can match the tires the same across each drive axle without concern for any discrepancy in diameter from front drive axle to rear drive axle, whereas on a Mack tandem, you must match tires the same front and back on one side and then do the same on the other side so there is not a great difference in average tire diameter from front drive axle to rear drive axle(keeping the larger 4 on the curb side to compensate for road crown).

I think Rowdy has the Mack air ride, which is made by Hendrickson and is identical to this: http://www.hendrickson-intl.com/products/product_detail/has_tandem.asp Those U bolts are tiny compared to the ones on any of the Mack camelbacks. If the U bolts have been on there a while, tightening may be impossible, and the U bolts may need to be torched off and replaced, then tightened properly, and retightened after running it for a day. I also use a 3/4 impact @175 PSI air pressure and tighten as tight as it'll go, whack the tops of the U bolts with a sledge a few times, then tighten some more till they don't tighten any further. .

Mid 70's - early 80's vintage, just prior to the debut of the "high sprocket" Cats. .

You were in "Heavy Spec Heaven". DM800's ruled that area in the late 60's, 70's and 80's. .

....And running it with the U bolts loose will eventually cause the "Z" bar to break right next to the saddle. .

http://www.bigmacktrucks.com/index.php?showtopic=12971 http://www.bigmacktrucks.com/index.php?showtopic=12973

Sounds like you're talking about the Rolling Stones (Keith Richards especially). lol.

Randy: The Tach drive is not on the inj. pump, it is under the pump, toward the front, sticking out of the block, pointing upward. It will have threads similar to what you saw on the back of the tach (but larger) where the tach cable screws on. Hope this helps. .

That would be the same as a D333T equipment engine wouldn't it? .

Of the ones I've dealt with over the years the 44k rears and the later style 87? on up 38k had 6 spoke hubs. I honestly can't answer that as I have never made that comparison. If they're the pressed steel housings, check real carefully for cracks in the area at the left front of the bolt circle. I've had several that developed cracks and resulting oil leaks in that area. If that's the case the housing can be welded up and ground down and filed flat at the mating surface. Is that what happened to the housing you spoke of earlier?

Best thing to do is check with your state DMV, as rules regarding that sort of thing vary from state to state. Find out for sure before spending money on a truck that may be useless if it doesn't have a title. .

Hi Rob. My 1972 DM685s triaxle had 38k Mack rears with 5 spoke hubs, as did all of the 38k rears in Van Handels fleet when I worked there. Regarding the width of the housing, I believe it would be the same. .

Wasn't that Steve Avella's B81 that had "Stray Cat" lettered on the grille guard? .

Also, if you put the throttle lever wide open with the machine in neutral, does the engine seem to rev all the way up as it used to when it was running right? If yes, then it's probably the previously described problem. If no, then it could be something as simple as the throttle linkage being out of adjustment, or the high idle screw being set at too low of an RPM.

It's a diaphragm looking thing with about a 3/8" dia. line hooked to it. The other end of the line would be connected to the intake manifold. When the turbo increases boost pressure in the intake manifold, the boost pressure comes thru the 3/8 line to the aneroid, causing the diaphragm to move, allowing the inj. pump rack to open all the way up. If this doesn't happen for one reason or another, the rack doesn't open all the way, the engine doesn't get full fuel, and the engine cannot produce full power. .

Sounds like the aneroid control isn't letting the rack go all the way open as boost pressure rises, due to a ruptured diaphragm in the aneroid control, disconnected or loose line from the intake manifold to the aneroid, or stuck parts in the aneroid or pump. Does that machine have an intercooler out in front of the radiator? If so there could be a boost leak in the cooler or connecting pipes causing a loss of boost pressure, which also will not open the aneroid control fully and will not provide sufficient air for full power. We had a similar problem on an old 980B with a 3306 engine. .

Reminds me of something that happened last year at the shop where I work. We got a factory rebuilt 3116 Cat engine for one of the 950F loaders. The engine came with a magnetic drain plug in the oil pan, but the machine application required a quick drain valve and drain hose. The head mechanic was switching parts over from the old engine to the new one, and when he removed the magnetic oil drain plug there was a bolt stuck to it! Cat was notified, sent a tech to the shop to investigate, said it looked like a bolt from the fuel rack. They pulled the valve cover and all required bolts were present, so Cat said to install it, run it and they would stand behind it if there were any problems. So far so good after a winter of plowing snow. May have been a bolt that was dropped during assembly and fell down into the pan. .

I've heard that he's "old school". He doesn't buy any new trucks, he buys glider kits and builds them with classic mechanical motors, just like the good old days. .

No. All the B42 series were gas powered.

Looks like a CH/CL dashboard panel screw to me. Look at your dashboard and you'll see what I mean. I concur that it probably got dropped in the oil filler, possibly by some smart ass while the truck was up for sale, then found it's way to the magnetic plug. The magnet did it's job.

Those transmissions suffered from the "range shift self destruction syndrome", so that later shift pattern was designed to allow the range shift to take place at a lower speed, thereby putting less stress on the range shift synchro. If he's looking for an on/off road transmission, that rules out the 2050 or 2060, as they don't have enough low gear reduction for that. .

I remember there was an O ring on the older ones, but any that I've ever dropped in I just made sure the mating surfaces were clean and then put silicone gasket maker on the diff mating surface, being sure to encircle all the bolt holes, then drop the diff in the housing. The reason I put the silicone on the diff and not the housing is that if you put it on the housing, any crap that falls while you're lowering the diff will land on the silicone. With the silicone on the diff surface that can't happen.

I can't swear to it Mike, but I would think so. .

PPG paint code 72182.

I would also think that the baby quad box would handle that little Cummins without a problem, those transmissions were also used behind the ENDT 475 Scania motors back in the 60's. Horsepower isn't the main concern, it's the torque output of the engine that matters. If you could compare the torque specs of the 475 to the torque specs of the 6BT Cummins that would tell the story. .