Full Floater

Oh that's great to know about. Did you install it with the pump still on the engine? Im sure MANY a old Mack could use that kit to buy them several more years out of some tires governor spring. Mine sure could

Every old Mack that I have operated has done a little bit of this after a cold start. It's always subtle, but they do it. ALSO, many seem to do the same when accelerating lightly (apparently this is due to worn governer springs in the American Bosch pumps). I do have 2 trucks that do this but run 100% otherwise. I do plan on sending the pumps out at some point to have the governor springs done to see if this corrects the issue. As time goes on and these trucks get older, it may become a more common problem that needs to get dealt with. If I had more time, getting that issue sorted would be much higher on my priority list.

If the engine is stamped B, yet doesn't have dynatard valve cover wires or a dynatard switch on the dash (I have not been under the valve covers yet to see what exactly is or isn't under there), could this possibly mean the engine has a dynatard cam, but just no dynatard stuff under the valve covers?

I believe the B is related to having a Dynatard, upon further research...however this one does not have the wires going to the valve covers, nor a switch on the dash... As for application, its in a single axle 1976 R685 that was left for dead. I bought it and am bringing it back to life, in hopes of giving it another round.

Hi. Picked up a new to me 76 R685 single axle. I thought it was a 237 but the tag says ENDT-675, 235hp and a 3B engine family. Can someone explain to me the difference in 237 and 235/ENDT-675 and 673? And what is the 3B engine family all about? Thanks.

Got the can changed out no problem. Now everything is working 100% again. That brake is fully releasing now. Which it wasn't before. Thanks again!

Very helpful tips guys, thank you. The boss around the air fitting is round. So I guess that would be standard stroke? All the other cans have round bosses as well. I will be going down to the truck shop today and will purchase a 30/30 can and see how it goes.

It appears that one of my brake chambers is not fully releasing on my 78 RS600L, w/Mack rear ends; and is in need of replacement. Are these just regular type 30 chambers, or are they anything specific being on a Mack?

Selling a 1969 NTC335 Cummins. Serial #679118. Built at the Columbus plant. Unknown mileage. Runs well. Can be seen running in truck. No leaks and no smoke once warmed up. 24v starter, Jakes 15 speed fuller trans. Asking $3000Cad, for the pair. I am located in Canada. They are still in a truck. A 67 Kenworth LW924. Its a parts truck only. No rear ends, bad frame. No title. Will Included the truck at same price or I can pull the engine/trans. Will consider trades. Looking for 11R22.5 tires, R model Mack truck for parts. International S1954's.

I have 4, 6 volt batteries in my 78 R model, that are on their way out along with the cables. I was thinking of converting to 2, group 31, 12 volt batteries to replace the 6 volts. Has anyone done this?

Ok I will phone the nearest pump shop in the a.m as they are closed today, and see if they want to do the job. Spill timed eh.... That's a new one to me and always have wanted to try it....here's my chance!!

Ok so pull the whole pump and have it checked out, ok. If I knew it was the springs, does the entire pump need to be pulled anyways? or can the back part be removed from the main body of the injection pump? Is there anything else I should have done to the pump while its at the injection shop? Its fairly low mileage, 220.000km so im hoping that it does not need a full rebuild

The external springs in the picture are the throttle return springs. They are both new but the horizontal one replaced what was there from the factory, or at least it looked factory. The other one is just an extra one that I put on for good measure, to be sure that this wasn't casing my issue. All it did was make the pedal stiffer. There is defiantly something going on as it hunts at idle and when I accelerate softly, it does it then to. Its like im going down the road and getting on and off the throttle every second or two, but in reality, im holding it as steady as I possibly can. The entire linkage is tight and no play anywhere So should I look at bushings instead of springs?? I have no idea where to start

Ok so im due for new governor springs in my 79 RS600L, with an EM6-300. Its doing the lopey idle thing with a lopey acceleration. I have never done springs before and this is my first Mack. So, what all is involved? I will be having an injection shop do the work but I need to know if I have to remove the entire injection pump or can I get to the springs another way? I don't even know where the springs are... Thanks fella's, Im looking forward to getting this motor that's in excellent shape, running smoothly!!

The 795GB363AP7 works! It hangs up a little bit on the bottom of the dipstick tube, but with a little finessing, it comes out. I can live with that.

Thank you guys. I will put it 80-90 as that's what I have a lot of.

Hi fellas! I am about to change the tranny oil in my 1978 RS600l with a 12 speed. Question is, what viscosity of gear oil do I use? Are any additives worth putting in to? Thanks a bunch, Kevin

What years were the early V8s? What were there issues?

So you're saying that's most likely whats wrong with the factory pump? Would you recommend that I dig into it and revert back to using it? I will if that's a better way.

Good solid info, thanks Terry. Kevin

Is that in fact a lift pump, or where the pump used to be? I don't see any lines going to or from it. Is it safe to run an electric in conjunction with the factory pump? Im assuming there was an air intrusion issue or drain back problem at one point and someone put and electric on there as a band aid solution. Im happy with how its been working however. I will be buying another electric lift pump to keep in the tool box in case it fails somewhere out in them bushes...

Here you are, pics of the pump. Yeah, that looks just like the electric pump that's on mine. What did these use as a lift pump from the factory? Did the IP pull fuel from the tank on its own? Im having what seems to be a common Mack issue, with it having an irregular idle from what I thought was worn governor springs; but im wondering if the electric pump is pushing fuel at a different psi then what the injection pump requires?? Just a thought that crossed my mind.....

I don't see a hand priming pump on the injection pump or anything that might resemble a lift pump

Oh nice!!!! Thanks so much. I will try that one next week!

The dipstick handle broke off on my EM6-300. Luckily I could fish it out of the dipstick tube...phewww..... This isn't the factory engine so when I ordered a new dipstick from Mack, they ran the trucks serial numbers and I got the wrong dipstick, part #795GB29301P3. They said the numbers of the engine didn't do them any good. The one they sent me had a twist to tighten handle with the rubber seal that expands. Mine had just a plain old hook handle, no seal or anything. It fit into the tube in the picture. Does anyone possibly have part # for an EM6 dipstick??