M39 series LDS 465-1A to Mack ENDT 673 repower

[AMGeneral]

Well,the job is finished,


I hope I never have to do another one by myself!!!

Things went smoothly on the replacment,probably because I have a 4500 Ford backhoe and a M62A1 5 ton wrecker at my disposal.

I did cheat a bit on the removal/replacement of the spring pack on the dump.

Rather than remove all 8 bolts securing the axle mounts,I simplt removed the touque rods from the axles, this allows the drivers side of the rear axles to slide to the rear or front about 6 inches each.

This proved to be much easier than removing the axle clamps and did not seem to over stress the other 8 torque rod ends on the opposite side of the dump.

Again,this is how I did it, you situation may differ.

Also note,the 2 trunnion bearing nuts are the same inner and outer nuts as the ones used on a 5 ton axle.



Pictures!!

#1- showing the trunnion cap removed and both torque rods disconnected from the center mount.

#2- the front spring pad,almost clear of the spring.

#3= the rear spring leaves,clear of the pad,with the axle returned to the normal position.
Note the 2 missing spring leaves

#4-the spring pack free from the trunnion.

#5-the trunnion axle itself,almost and exact copy of an axle tube on a 5 ton.

#6- the truck back together and ready for road testing.

 

[EMD567]

Brandon,

What did you use to move the ends of axles forwards and backwards? From the pictures, it looks like a simple job, except for the size of the components.

 

[AMGeneral]

Brandon,

What did you use to move the ends of axles forwards and backwards? From the pictures, it looks like a simple job, except for the size of the components.

I used the 4500 Ford and a 1/2 inch chain.

 

[AMGeneral]

Well, I finally got a chance to test the dump out today,

After a short drive to the fuel dump(station),I came home and fired up the backhoe and loaded a small amount of stumps,dirt and root scrap in the dump.

It dumped ok,but it seemed to stutter a bit,like it was starving for oil or bypassing a bit,

So Now I get to pull the pump and control mechanisim to inspect it for wear or a possible broken relief spring.

 

[budman67]

Is it possible to go from a Mack to a multi,the only 5tons I see are non multi fuel in the for sale section?

Edit: I have asked this in the past,but what is it that is the issue,frame length?

 

[budman67]

Could someone answer, I searched through my posts and searched the forum,but
the answer eluded me. I remember someone saying you can go one way,but not
the other.

Perhaps I am not asking the search the right question?

 

[AMGeneral]

Is it possible to go from a Mack to a multi,the only 5tons I see are non multi fuel in the for sale section?

Edit: I have asked this in the past,but what is it that is the issue,frame length?

Yes,you can swap engines from a Mack to a Multifuel,or from a Mack to a gasser,or from a Multi to a gasser, there is no issue with frame lengths on the older M39 series trucks.

The only frame difference is the small cutout mentioned earlier in this thread,only associated with the Mack engine.

Having owned and driven Gasser,Multifuel and Mack powered trucks,I judge the Mack to be the pinnacle powerplant in the 5 tons as far as power is concerned.

If you are seeing the 800 series trucks in the classifieds,then NO,you cannot swap engines that readily because that series truck was designed specifically around the NHC 250 Cummins.

 

[budman67]

I remember they said I would have to change the air intake to the passenger side, but that is all I remember.
Finding these MF 5 toners are rare now. Lots of 2.5t, I wish I could find that thread.

 

[gimpyrobb]

Brandon, what is your preferred method for popping the dog bones out?

 

[AMGeneral]

Brandon, what is your preferred method for popping the dog bones out?

8 lb sledgehammer.

No sense in dragging the 16 or 20 lb out for that small of a job.

 

[AMGeneral]

Well, I finally got a chance to test the dump out today,

After a short drive to the fuel dump(station),I came home and fired up the backhoe and loaded a small amount of stumps,dirt and root scrap in the dump.

It dumped ok,but it seemed to stutter a bit,like it was starving for oil or bypassing a bit,

So Now I get to pull the pump and control mechanisim to inspect it for wear or a possible broken relief spring.

Well,I got a chance to pull the pump and check both springs for wear/distortion,they both seemed serviceable.

The TM9-2320-260-34-2 section 15-19 did not show the upper relief valve in detail,although mine had a 1/8 inch hole drilled in the upper portion of the valve itself, I am not 100% sure it was supposed to be there.

with a fluid change and a few linkage adjustments,it did dump better,just not what I think it should be.

 

[AMGeneral]

Well, I managed to do a few more "adjustments " and refittings on the M51A1 dump in the last week.

I converted the oil pressure gauge to a manual gauge with 2 sections of 1/4 in ID high pressure hose(5000 psi) and crimp on fittings with a Murphy Switchgauge for the gauge head.

I used a model# 20BPG-100 gauge (0-100 psi) ,I had intended to use a M series air pressure gauge, but the Murphy gauges were free.

I also bumped the fuel up on the IP slightly on the Mack, it's a bit more complicated than a Multifuel, but doesn't require many more tools.

The power increase was immediately noticeable after a short test drive.

 

[AMGeneral]

Well,It seems the 673 in the dump has the same problem as the other early production 673 I own,worn cam lobes!!

This engine has always had a sharp rapping sound in the rear head/block area,definetly a tappet/cam lobe going bad.

So,after some checking cam lobe lift with a dial indicator this evening it appears the intake lobe for #4 cylinder and the exhaust lobe for #6 cylinder are worn down about .022 thousandths each.

It appears that a cam and tappet replacement are in the works for this truck as well.

 

[Ferroequinologist]

We need to get a fresh cam sent to China and say, make us some of these.

 

[AMGeneral]

We need to get a fresh cam sent to China and say, make us some of these.

Well,there are new ones still produced here un the U.S.A,look under the heading for an E6 engine.

http://blakesreman.web13.hubspot.co...sc=84826758.2.1387895731728&__hsfp=1954684341

 

[Artisan]

We need to get a fresh cam sent to China and say, make us some of these.

It is easier than you think.

Just go to www.mfg.com and sign up and put it out to bid.

Believe It!

 

[AMGeneral]

I finally had "soldier B" to run the camera yesterday for a short vid of the dump at work!

8 tons of 1 1/2 wash stone for the driveway.

https://www.youtube.com/watch?v=GZJGypiXB-s