FIXED - stuck on side of hwy..cannot replace water pump belt

[DeuceNewb]

***UPDATE:: Made it home finaly!!!

I'm in Maryland stuck on the side of the road because I lost the belt that drives the water pump in my 9series 5ton . I bought a new one from a napa down the road and cannot get it on! Just to be clear, the belt I bought has a part number 25-22425

I've read instructions online about how with the nhc250 you have to loosen the bolts around the water pump and rotate the pump itself to adjust belt tension. I cannot get it to budge. I got it loose enough that coolant was leaking out and yet could not get anything to budge.
Can somebody give me some clear instructions on what exactly needs to be moved in order to get a new belt on? What exactly is the part that turns.
I used twine to make a belt that got me to a gas station before tearing to shreds, and a longer belt from autozone that i got to go over both pullys won't turn the pump and just slides.

Lucky for me my aunt lives 45 min away and I just got to her house for the night, truck still at the gas station. I will be returning tomorrow morning to start again, and will end up removing the whole pump if i have to. If you are nearby to the intersection of route 32 and 1 (not too far from Ft Meade near baltimore) and could offer a hand It would be wonderful. I've still got to make it all the way back to north carolina.
I do have a smart phone so i can check this thread and read what has been posted or you can call me at 919-619-eight937 or my dad at 919-616-one774 if you have any tips on how to make it easy.

Also, any pics would be helpful in explaining exactly what i need to do

 

[WillWagner]

The water pumps can be difficult to move and most of the time the copper seal will leak after the pump is moved. You are doing it correctly. Try getting a bar that fits in the slots, put some tension on the pump and give it a love tap with a hammer, spray some sort of lube on it.

 

[juanprado]

I feel your pain. Same thing happened to me on my recovery from Fort Polk. The water pump is eccentric (off center) on the round housing that is why you need to rotate it. Make sure you are loosening the pump housing bolts and not the outer bolts on the front mounting flange. It sounds though you have the correct ones since it is leaking coolant.

I used a heavy duty screw driver to wedge inbetween the ribs of the water pump casting and the pulley and beat it to get it to move. I even chipped off part of one rib in the process. Once I did get it to move, I put the belt on it and re tightened it. You do have the correct part number for the belt. It only uses one belt as the other groove on the pump is empty. My pump would not stop leaking since the copper crush gasket sleeve had been disturbed. I ended pulling the water pump and replacing. It is not an easy pump to find in stock.
NAPA Midland/haldex rw1174x. It came with a much wider and thicker gasket than OE. Felpro diesel does sell the gasket individually. It uses the same part number as the cummins part number but no one stocked it. I special ordered it at the same time from NAPA to be safe but did not use it since the midland pump had a better one. I also changed the pump since I was unsure of the mileage and it looked original to the engine. Same color as the engine and I assumed it to be OE with over 25 years. New or rebuilt pumps are normally casting grey and not painted.

I installed it and used liberal amounts of Permatex RTV ultra blue with the crush copper gasket. TM says grease and I just could not bear to do that since it such a pia. Rtv gives you time to rotate it and tighten the belt. I understand it will leak if disturbed down the road but since it already leaked previously, I do not see the point. Make sure all the coolant drains so it is dry when you glue/assemble. System holds 37 quarts. I drained using the radiator petcock. As you will see 37 qts makes one heck of a mess on the ground.

To gain access and make it easier, I removed the fan and clutch along with the 1/4 upper radiator shroud on the passenger side along with the upper hose and radiator support plate at the top of the motor. I would change the fan clutch and power stg belts at the same time. I had taken the fan clutch off so those belts were off and I loosened the power stg to make it easy. Those belts are straight forward to change and adjust. Some bolts were pitted on the pump and fan clutch and I ended up changing some of those fine thread rascals. I also used anti sieze on all the bolts when reassembling.

The problem I believe it that is such a bad design and since the belt is not easy to change it is not routinely done on pm.

I had recommended on some other threads to buy a power twist link belt to use in an emergency to get you off the road as a short term measure similar to what you did with the twine.

One other note is to flush the system since you are bone dry. My anti freeze was nice and pretty green when it leaked but some where was a pocket of rusty sludge that I found when I flushed it and drained it repeatedly with just plain water. I suspect in the coolant tank but not sure. Once I got clear water I refilled since it takes lots of gallons of not cheap antifreeze and water 50/50 for my area. Remember to add additive also to the system.

I hope this helps. Good luck and God's speed.

 

[goldneagle]

If I remember correctly its counterclockwise to loosen and clockwise to tighten the tension on the belt. It was a PITA to get on to the pulley. We had the pump all the way towards the IP and it still required a slight turn of the engine to seat it once we got it started on the pulley.

 

[doghead]

Here's a pic of the adjusting bolt. You need to back it off to make "slack" to install the new belt, then tighten it after the belts are on. Of course, you have to loosen those other bolts that allows the coolant to leak out some. This pic is from the 809 series, but I believe they are almost the same.

The red arrow points to the adjust/tension bolt.

 

[73m819]

I feel your pain. Same thing happened to me on my recovery from Fort Polk. The water pump is eccentric (off center) on the round housing that is why you need to rotate it. Make sure you are loosening the pump housing bolts and not the outer bolts on the front mounting flange. It sounds though you have the correct ones since it is leaking coolant.

I used a heavy duty screw driver to wedge inbetween the ribs of the water pump casting and the pulley and beat it to get it to move. I even chipped off part of one rib in the process. Once I did get it to move, I put the belt on it and re tightened it. You do have the correct part number for the belt. It only uses one belt as the other groove on the pump is empty. My pump would not stop leaking since the copper crush gasket sleeve had been disturbed. I ended pulling the water pump and replacing. It is not an easy pump to find in stock.
NAPA Midland/haldex rw1174x. It came with a much wider and thicker gasket than OE. Felpro diesel does sell the gasket individually. It uses the same part number as the cummins part number but no one stocked it. I special ordered it at the same time from NAPA to be safe but did not use it since the midland pump had a better one. I also changed the pump since I was unsure of the mileage and it looked original to the engine. Same color as the engine and I assumed it to be OE with over 25 years. New or rebuilt pumps are normally casting grey and not painted.

I installed it and used liberal amounts of Permatex RTV ultra blue with the crush copper gasket. TM says grease and I just could not bear to do that since it such a pia. Rtv gives you time to rotate it and tighten the belt. I understand it will leak if disturbed down the road but since it already leaked previously, I do not see the point. Make sure all the coolant drains so it is dry when you glue/assemble. System holds 37 quarts. I drained using the radiator petcock. As you will see 37 qts makes one heck of a mess on the ground.

To gain access and make it easier, I removed the fan and clutch along with the 1/4 upper radiator shroud on the passenger side along with the upper hose and radiator support plate at the top of the motor. I would change the fan clutch and power stg belts at the same time. I had taken the fan clutch off so those belts were off and I loosened the power stg to make it easy. Those belts are straight forward to change and adjust. Some bolts were pitted on the pump and fan clutch and I ended up changing some of those fine thread rascals. I also used anti sieze on all the bolts when reassembling.

The problem I believe it that is such a bad design and since the belt is not easy to change it is not routinely done on pm.

I had recommended on some other threads to buy a power twist link belt to use in an emergency to get you off the road as a short term measure similar to what you did with the twine.

One other note is to flush the system since you are bone dry. My anti freeze was nice and pretty green when it leaked but some where was a pocket of rusty sludge that I found when I flushed it and drained it repeatedly with just plain water. I suspect in the coolant tank but not sure. Once I got clear water I refilled since it takes lots of gallons of not cheap antifreeze and water 50/50 for my area. Remember to add additive also to the system.

I hope this helps. Good luck and God's speed.

This is WRONG, DOING THIS WILL MAKE IT HARD or IMPOSSIBLE TO ADJUST IN THE FUTURE (a NEW belt WILL require this), use a lot of anti-seize, the reason the 855 water pump is hard to adjust is the ORGINAL or a pump R&R install was dry, if installed this way the gasket will leak every time after a adjustment because the movement gules (sp ?) the gasket.

Not a bad design if the install is done correctly, being LAZY or not knowing what you are doing is not a 855 design flaw but a human flaw, The water pump will adjust without the leak if the anti-seize is used, may still be hard to do, doable.

 

[WillWagner]

Yeah, I kinda forgot to insert the use antisieze part. If you use silicone, sure it will not leak, but it will be extremely difficult to re adjust the belt after it's initail stretch and it'll probably leak again if you get it to move. Use antisieze.

 

[juanprado]

That diagram is not the correct one for a M939 water pump. All the housing bolts need to be loosened around the circular housing. It is also not the correct water pump.

As I stated my original pump leaked after I rotated it and but the new belt on. Obviously the way it was originally assembled did not do the job and I could not tell if grease or anti seize had been used. Bottom line, it had to come off to replace the gasket and I chose to spend an extra $100 to have a known good pump. No sense in the pump going bad down the road and redoing the labor.

I can justify the RTV, as I do not expect to have to ever change the water pump or belt anytime soon. The original water pump was not leaking due to the pump but due to the cooper crushed sleeve losing its ability to seal since it was disturbed.
Midland/haldex used an upgraded gasket much better than OE. The felpro gasket I also ordered was the same thin skinny copper as the original. The gasket sleeve gets crushed in place.

Many folks here have reported their m939 pumps leak more than than those who have not attempting to change the belt. Once a gasket is dis-formed , I doubt anti seize will allow it to be reused. Hence the reason I used RTV as cheap insurance for a solid seal. This is a major job that took a considerable amount of time even with my helper son. It was my first time on this engine so I was way behind the learning curve but not a simple 10-20 min belt change as every other automotive/truck belt I have ever changed.

I have sold parts for 20 years and can not think of any other engine family automotive or HD that uses an eccentric water pump rotated to adjust the belt. I also notice that Cummings dumped the design. It is a poor design especially for a military vehicle needing a field repair that needs to be done in a hurry. The automotive aftermarket does not use anti seize or grease to seal gaskets. I am not versed on the 800 series using the same engine.

Using a high quality belt, most of us will use these vehicles very little miles. I consider my pump and belt will last another 10-20 years, I am happy. My m923 had 9000 original miles from 1984. No clue on the belt but I suspect original due to the water pump paint matching the engine.

 

[doghead]

That diagram is not the correct one for a M939 water pump. All the housing bolts need to be loosened around the circular housing. It is also not the correct water pump.

Oops, heres a pic from the TM, of the correct water pump. The lower pic insert shows hot to adjust the tension.

 

[73m819]

The ANTI_SEIZE allows the water pump to be adjusted and NOT guall (sp?) the gasket, AGAIN NOT a poor design, if done right there is no leaks, the 855 has been around for a long time, in everything from boats, gen. sets, cranes, trucks, on and on. The wp gasket is not changed every time the W/P belt is adjusted, few from it, almost never, but then we are talking about a correct install to start with,
DA, It would NOT have been stated in the TM "GREASE" for the W/P install unless there WAS A good REASONt, grease works only ANTI-SEIZE works better, If RTV was called for, you had better believe it that the TM would say so.
When your NEW BELT stretches after some use and you go to ADJUST, be ready for a fight AND leaks because of using RTV which means a correct REINSTALL.

Selling parts is a LOT different then INSTALLING parts, the SELLER sees a lot of the aftermath of a bad install and the bitching about the BAD design, never here that the installer screwed up.

The bottom line is doing something RIGHT the first time or just keep doing it till it is done right, either way it ends up done right, though the second way takes a LOT more time and money

 

[Ferroequinologist]

I've replaced my belt on the XM818 three times- once when I got it, once when the pump failed, and once on the road when another belt failed and caught in the water pump belt.

The first time, I loosened all the bolts, rotated the pump with a screwdriver, put the new belt on, tightened it up, and torqued the bolts down. Never leaked.

Second time, I pulled the pump out, put the new pump in, did the antiseize, and put the new belt on.

Third time, did on the side of the road, same as the first time, hasn't leaked to this day.

The engines are almost exactly the same between the 809 series and the m939 series. Only some little things and externals are different.

My first replacement belt, gotten using a PN posted here from Napa, required me to rotate the engine a little to get on.

The second two belts, were obtained from Cummins, and they will slip on without rotating the engine.

I wouldn't say it is a bad design, the 855 blocks in our 1941 locomotives are exactly the same water pump. I would just say they moved on to a different design after 50+ years.

 

[swbradley1]

Sorry Ron but I have to disagree. Just because it works doesn't mean it isn't a design flaw.

Not having a good way to adjust the belt without loosening the water pump is a poor design. It doesn't matter how many of them have been used or where.

IMHO

 

[73m819]

The wp drives off the accessory drive pulley, there is not much space to put a idler

Also if this wp drive belt adjustment WAS a problem, Cummins would have changed it as a factory update, because if this was a major problem to the users, Cummins would have LOST money big time, NO company likes unhappy customers

 

[hemichallenger]

The 855 did go to a differnt water pump that they used a idler on and that was used through the n14 and it uses a small water pump belt thatb is a lot easer to adjust.

 

[vtdeucedriver]

And I thought the MF had issues with the compressor pully........................now where is my compressor wrench? Im going to lovingly kiss is after reading this thread.

 

[73m819]

The 855 did go to a differnt water pump that they used a idler on and that was used through the n14 and it uses a small water pump belt thatb is a lot easer to adjust.

Could this update be used on the NON-idler 855s

 

[swbradley1]

Interesting. There is a big truck salvage yard down the road. I wonder if they would let me look...

Now to find the time to stop by.

 

[juanprado]

How did you do?

DeuceNewb?

How did you do? Did you get to your LZ? Please update us!

Juan

 

[DeuceNewb]

thank you for all the help and advise. Was able to figure out that we had missed one bolt, but even after that we were doing everything right and it would just not budge. Thankfully somebody suggested to use legs from pantyhose, and that's what worked!!!

Bought a 3 pack of pantyhose and used 5 of the 6 legs. After a few methods, it turns out the best method is to do a single wrap around, tie a double knot, cut the excess and put a small piece of duct tape around the knot. This method gave about 120-130 miles each!

For now on I will always keep a pair of pantyhose in the truck in case the belt for the water pump ever breaks again.


I'm now at my parents house where I can stay for a few days to fix it thr right way before driving the last remaining 160 miles to my place.

 

[doghead]

Glad to hear you'll have time to fix it right.

I would not want to be around if you had to ask your mom to borrow some pantyhose for the ride home!

If you ever loose a belt down in Alabama, I heard Wreckerman wears them.