excavator

Hi guys One of my trucks is 1973 Mack R600 single axle dump that we run every day moving our equipment with 1988 tag trailer. We just bought new talbert trailer and none of the LED lights would work on positive ground. We also pull new trailer with our newer truck so only option was to convert 73 Mack to negative ground. We upgraded the engine few years back to 300 tip turbine. It had the 2 wire alternator so we just switched all wires around on alternator. We switched cables on batteries. I had to swap out the volt meter and coolant gauge and reverse the heater wires around. Switched wires on cigar lighter and now all is good. Starter works, alternator charges normal and all led lights now work with new trailer

I have a Sheppard 492 s 5 steering box that I removed because seal behind pitman arm is leaking. My local parts supplier sent it to a re builder and after a week they are having problems locating seals for the Job Any one here have source for a sheepard 492 box?

Just picked up this this 1986 RD686SX from one of my customers who upgraded to a Granite. He said it was getting too old, heat and air dont work, engine brake dont work, foot air valve leaks dump body has rust,air gate dont work. After 2 weeks in my hands all works great now.

sounds like your way worked well all those years and cant ind the SPECIAL wrench any way

this is the tool book shows to loosen lock nut and back off screw before adjusting yoke adjuster screw

Hi guys, I have a 1986 Mack RD dump that I just picked up and I am looking at my Mack book on how to adjust the dynatard 4 valve engine. I have no problem following the instructions other than is it required to use the SPECIAL tool as shown in book to loosen the lock nut on the hydraulic side. The tool is not available and I don't believe it is a must have. Book explaind to use special tool to loosen locknut and back out adjuster then using feeler gauge on yoke side adjust the yoke while holding pressure down using .010 feeler. Seems like the tool is not required. I have adjusted many 2 valve mack engines with dynatard cam but this is first 4 valve

Hey thanks for pic Mine looks just like the pic however the switch that was in there was not hooked up and is only 2 position. I will get a 3 position and see how that does. Do you know how many wires plug into 3 position switch in that pic

Ok thanks. I can get ac to work but I just don't know if it is right way. May not matter much as long as it works

Hey thanks. The rocker switch is only 2 position and might be the wrong one. Does anyone know if it has 3 position as heat max ac and ac

Hi guys I just picked up another old Mack a 1986 RD tandem dump. It has the 3 round style vent holes in air heater box and a single rocker switch in middle that was not hooked up to wires in rear of box. When I try plugging in wires I can get the ac to work but I also see the center cab vent outside of cab opens and I am trying to figure out how or why it opens and if it should. The outside vent on old r model has manual knob to crank open. This one has air line to it with electric switch also

thanks for reply

I had many mack tandems but this R685t single axle I have needs gear oil fill and I don't have proper instructions. The lower rear as fill plug but the top has 1 fill plug on top and I need to know how much to add. Any help would be great

few pics of my oldies. I just finished installing EM6 in the 1973 red mack dump

Had to post this

I am installing this e6m in my 1973 r model that has a tired 237