CML Service

When dealing with a oddball input shaft I don't concern myself with the splines. Many times just looking through the socket drawers I can find a socket that slides into the spline then another socket that slides into the pilot. Then hopefully the socket for the pilot fits into the other socket (maybe a little tape to increase it's diameter) and you have a tool. The other solution I use is to machine one on the lathe (still only round no splines) anything you might have laying around steel,aluminum, wood will work. Don't overthink or overengineer it, nuts, bolts, washers, pipe, anything could become your tool. Chuck

Cracked blocks are not always terminal. Many common water jacket cracks are easily repairable. I have seen engines run for years with unrepaired cracks that seep. I even have at least one farm tractor that I bought with a poorly repaired crack. It seeps some from under the "stuff" that was smeared on it but I have no desire to find out what is under there. Chuck

Napa is a good source. I was able to get a kit for a Stromberg on one of my forklifts. Note that Stromberg may be listed under Bendix. Chuck

I'm pretty sure all Mack cams were compatable with Dynatard since the mid 70's. Dynatard is a much easier install with the tip fan intercooler. Dynatard also uses a switch actuated by the fuel rack so will not stall the engine. You could use that switch on a Jake also. Chuck

Try lifetimetruck.com . I put thier corrugated stainless fenders on my truck. When all was done buying fenders and polished stainless brackets I spent nearly $1000. Chuck

There are driveline PTOs available (like on a fire pumper). But whether they reverse the rotation I'm not sure. You may want to check with the fire truck guys. Chuck

According to the original delivery info it was sold as a truck tractor to a leasing company in Mass. The original line sheet is hard to read (bad microfilm) so I can't tell what it had for fifth wheel. Right now it has a hydraulic fifth wheel and spent a lot of time as a yard horse. There are a couple pictures of it in my gallery. Chuck

Thad is right the visability was a "selling point" other opinions vary on this. Another reason is the engine sits back into the cab so the offset moves you away from it. With the engine moved back it shortens the hood for visability and manuverability. Not a bad truck to drive. A single axle with a 28' pup trailer and you can get into places a straight truck can't. Years ago that's the combo I took my driver test with. A company I worked for had a drive that peddaled freight in Boston and he refused to use anything else. One day they sent hin a brand new IH wit A/C and all the comforts. He told then he wanted his old U model back or he would quit. It seems the old Mack got around the city better and in and out of tunnels so they did send him his truck back. Chuck

U models are very similar to DM (dump and mixer) chassis. They are generally just a lighter chassis. The door tag numbers will tell a lot about the model (ex. U685S) Even though usually lighter chassis they can be spec'ed quite heavy. I have a U609T that was factory equipped with a 29,000 lb single axle rear. Chuck

Could be several reasons the shutters don't close. 1) Perhaps they are not designed to close such as a gas engine model. 2) The air may be shut off. On the passenger side of the firewall in the engine compartment there is a filter/oiler unit for the shutters. It may look like a carburetor bowl. There is a shut off valve there on the flexible line. 3)The shutter stat may not be working. Follow line from filter/oiler to the shutter stat on the water manifold. 4) Bad air cyl or frozen linkage follow line from shutter stat to air cyl. Check for leaks or binding. Thats about all there is to the shutter system. The shutters should close after start up once you build air press and only open when needed for cooling. Chuck

Yes I believe the 3126 took the place of the 3116. The 3126 is all electronic with unit injectors. Chuck

Hi folks, I'm looking for a little info here. I'm working on a 2000 Ford F750 with a Cat 3126 210hp. Truck seems to run OK and can achieve 70mph road speed. But as soon as it sees a hill it starts slowing down. All filters are fresh. As a matter of fact it was just at Ford for this problem and they said "we fixed it, the filters were clogged". Truth is filters had less than 100 hrs on them and the problem is still the same. I checked with the local Cat dealer they didn't seem very hopefull. They told me they don't have a chassis dyno so they couldn't check advertised HP. All they said was we could look into it for $110 per hr. They did hint at possible boost press problem though and said press should be aroud 20. So I hooked my laptop up to the truck and even though I only have IH software I could read some engine info. I found on a road test max boost was 19.75 and as soon as you hit the hill the boost started dropping. When you got down to 45mph the boost was only 15.35 is this normal? Any suggestions? We have other trucks (IH 215hp) that will walk away from this one even when pulling a trailer. This is a problem we recently noticed while traveling in convoy to upstate NY to do storm related power restoration. Since I'm the company mechanic I'm the last in the convoy and this problem truck gets us way behind. Chuck

Matt, RS type frames use narrow spring mounting same as early R. If you would like to take measurements I have RS, early R and B models sitting here. Give me a call. Chuck

Sounds like the R model's numbers may be jumbled. R690T is OK but the 9T6546 doesn't seem right. A R609T6546 would be about right for a 1967 single axle tractor. The U model sounds like a tandem axle tractor. Chuck

I don't see any advantage to removing the exh brake. Wouldn't it be better to understand it's function and repair it? You say your exh is cracked. Depending on how badly, it could effect many things including you perception of the engine brakes performance. As for $800 for exh parts consider if this is a working truck time spent working on it is costing you money. The factory parts should fit and do thier job correctly without extra trips to the parts store. Also be aware that DOT has rules about flex pipe usage, they especially don't like any long length of it. Then no matter who is doing it it's difficult to get multiple pipes to seal and stay in place with clamps. It's no fun to melt an air line and have to deal with it on the side of the road. Please don't take this the wrong way. I've been a mechanic for 25+ years and have dealt with the results of quick or inexpensive repairs. If you value this truck why take chances, the factory engineering got it to 600K miles. Chuck

Speedo cable really isn't anything special for B model. You just need to measure the lenght then the dealer can get it for you. It wont look identicle but the ends will work, same for the tach cable. Be sure to check all the related parts to be sure they are not worn or siezed. Chuck

In the past when ABS sensors gave problems we would push the problem sensor all the way into the tone ring while on a jack with someone turning the wheel. That often cleaned the sensor and ring solving the ABS code problem. Chuck

Paul, Euclid still sells most of that hardware and it is availible through Fleetpride and other truck parts dealers. Chuck

Hi Adrian, I like quiet so for my 66 R600 I used a RD/DM type chassis mount muffler and was able to get an offset stack very close to the cab to clear the body. I should have part numbers for pipes muffler and brackets if you need them. Chuck

The old trucks used grease. Some were converted to oil which often performed better than the grease that was availible in that time period. Now many new trucks have returned to grease and even beyond that to non-sevicable front wheel bearings. I prefer to use grease on my older trucks. Less chance of leaks and the modern grease is many times better than what these trucks were designed to use. Chuck

Those bolts are used on suspension and crossmembers. I believe the tool numbers are Kent Moore as that is who makes the reamers. If you are thinking of buying them check the price first they were rather expensive when I bought them. Chuck

When I separated my frame rails I started with an air chisel and a flat hammer bit to loosen the rust. Then a large firewood type wedge in the end all the while with more hammering from the air chisel. Then when the gap was too big for the wedge I slipped in a portapower jaw type spreader I could keep sliding this farther in with it's hyd hose. Once the frames were apart a needle scaler takes the heavy rust of fast, that will make the sandblasting go much faster. The frame bolts Macks calls "body bound" thier shoulders have a interferance fit that requires a special reamer, and it is a odd size that is not availible through industrial supplies. These bolts can somtimes be purchased from other sources Huck fasteners makes them as "Huck Fit" bolts. With any of these type of bolts the shoulder length is critical and generally 2 flat load washers are used. There is an entire section in Mack manuals on frame repair and proper bolt selection. Chuck

Dale, I would check for a sticking cam first. If you have the old iron shoes the cam ramps slide on the wear pads (they don't have rollers). After sitting the wear pads sometime rust or gum up and won't let the cam return. I've reached into the rear drums and sprayed them with a teflon lube. It seems to work good but the fronts you may have to pull the drum becase of full backing plates. Chuck

Welcome Sylvester, I think we may have talked on the Cat board. You should find a serial number on the rt frame rail rear of the rear suspenion. If I remember the chassis tag is on the seat base on the passenger side. Chuck

Some of the newer air driers like the Bendix AD-SP have a longer purge that will sound like a air leak from the bottom valve, but only for 10 seconds or so. Chuck