LMTV Alternator Disaster, engine now catastophic

[aleigh]

I haven't really considered using instruments to gather more vibration data. I've fixed most everything on mine now, so I'm not sure what I would find, except control data. I think if you break one "extremity engine accessory", have the driveshafts checked, and they are out of balance/runout, you've emperically found the problem. If you break multiple things and find that the driveshafts are good, that would be the real puzzler. It's unfortunate there isn't a good way to perform a driveshaft balance / runout test in the field, besides to wiggle it and look for the presence of play.

I don't know what you use your truck for but if it's as bad of an issue as you suggest, then, I'd say you want it for the day you whack a weight off the shaft when offroading, or the ujoints fail for other reasons (wear, water ingress, etc). If $1000 to have the shafts spun is (500 ea was mentioned on this thread) is cheap insurance, then a vibration monitor also seems like cheap insurance.

Personally what is also cheap insurance that I haven't heard mentioned here is marking the bolts and then a program of checking the engine to see if they are backing off, and safety wire (all common in other safety critical applications).

 

[coachgeo]

There are android and probably IOS apps that measure vibration. Not sure how one could utilize this option but..... it is an option.

 

[Awesomeness]

If $1000 to have the shafts spun is (500 ea was mentioned on this thread) is cheap insurance, then a vibration monitor also seems like cheap insurance.

If there is nothing that needs to be rebuilt on the shafts it's only going to be about $100/ea to have them straightened and balanced. I'd be interested to see what kind of "cheap insurance" vibration monitoring system could be had. I never even looked into it because most of it is expensive and bulky (not easily mountable). Maybe that's an incorrect assumption but I work with a lot of this type of equipment, and what I always use is large rackmount analyzers / data recorders that are about the size of a PC case, and instrumentation sensors that cost several hundred dollars each. Maybe they have smaller, more handheld / portable equipment that would work, at a reasonable price? My intuition is that nothing about such insurance will be "cheap", and will be scientific instrumentation that is outputting data but not simple indicators that would tell you "It's about to break!". If I'm wrong, that would be awesome, and I would install it right away.

Personally what is also cheap insurance that I haven't heard mentioned here is marking the bolts and then a program of checking the engine to see if they are backing off, and safety wire (all common in other safety critical applications).

Yes, marking is absolutely a great thing. I did mention using the safety tab plates that come with good u-joints - those bend up against the heads of the bolts to prevent them from turning. You can make them for any bolts using a little piece of sheetmetal. Also, clean and use blue (medium strength) Loctite on everything.


You can see the safety tab plates here. You put them on before you put the bolts in the caps. Then you fold up one of the tabs against the bolt (save the other tab for if you have to remove and reinstall the u-joints at a later time).

 

[DOUBLE ALT]

Aleigh I have been trying to tell the Military that some engineers were not on the same page when they designed the alternator and the mounting brackets. The holes, the bolts, the sizes, the design, do not match. All the field people say - well we are waiting for a new design. My alternator fixes their mistakes. Larger bolts, lighter alternator by 22 pounds, elimination of external regulator/s, how to beef up bracket, just part of the fix. Double-alt.com

 

[Duckworthe]

A few points:



2. I've read a few trucks have the fan blades go through the radiator. Would be be possible to fab a metal(steel) shield to protect the radiator from the fan?



I built a expanded metal guard for my radiator. It will bolt in with the fan shroud. Cost- about 6 bucks. Radiator-? $1000.00?

 

[Duckworthe]

Personally what is also cheap insurance that I haven't heard mentioned here is marking the bolts and then a program of checking the engine to see if they are backing off, and safety wire (all common in other safety critical applications).[/QUOTE]
That is a good practice to get into. I mark all my bolts as I go through items with a white or yellow paint pen. It is a great way to do my visual checks. I start with the lug nuts! Again, I'm glad you stated that.

 

[Adventure Driven]

I second this, I have a handful of paint markers I use in my shop

Seth

Personally what is also cheap insurance that I haven't heard mentioned here is marking the bolts and then a program of checking the engine to see if they are backing off, and safety wire (all common in other safety critical applications).

That is a good practice to get into. I mark all my bolts as I go through items with a white or yellow paint pen. It is a great way to do my visual checks. I start with the lug nuts! Again, I'm glad you stated that.[/QUOTE]

 

[Awesomeness]

Aleigh I have been trying to tell the Military that some engineers were not on the same page when they designed the alternator and the mounting brackets. The holes, the bolts, the sizes, the design, do not match. All the field people say - well we are waiting for a new design. My alternator fixes their mistakes. Larger bolts, lighter alternator by 22 pounds, elimination of external regulator/s, how to beef up bracket, just part of the fix. Double-alt.com

Interesting product. I have a couple questions...

1.) Will the Double-Alt run submerged like the military unit will?

2.) Why do you think the military chose a brushless design, while you choose brushed? What are the advantages of brushless?

3.) Why does the cooling duct come out the front (pulley side)? Wouldn't it be easier to route the tube if it came off the back? Do you have a duct for it that has the inlet on the back?

 

[aleigh]

I'd be interested to see what kind of "cheap insurance" vibration monitoring system could be had. I never even looked into it because most of it is expensive and bulky (not easily mountable). Maybe that's an incorrect assumption but I work with a lot of this type of equipment, and what I always use is large rackmount analyzers / data recorders that are about the size of a PC case, and instrumentation sensors that cost several hundred dollars each. Maybe they have smaller, more handheld / portable equipment that would work, at a reasonable price? My intuition is that nothing about such insurance will be "cheap", and will be scientific instrumentation that is outputting data but not simple indicators that would tell you "It's about to break!". If I'm wrong, that would be awesome, and I would install it right away.

I've seen hand held meters, but what I was really thinking was something made for aircraft. Not "cheap" depending on your definition, but as a reference, look at the Insights G3. You pick up a six channel EGT, GPH fuel meters, and vibration monitoring in one compact package. They go for about three grand. Depending on your perspective though if you figure a multi channel digital EGT is worth at least 1500 then you're only another 1500 for the vibration. I'll look around and see what's available, though. Something conceivably be done with an arduino and an off the shelf sensor too. There are plenty of multi-axis sensors available. We use them for inertial input for drones.

 

[Awesomeness]

I've seen hand held meters, but what I was really thinking was something made for aircraft. Not "cheap" depending on your definition, but as a reference, look at the Insights G3. You pick up a six channel EGT, GPH fuel meters, and vibration monitoring in one compact package. They go for about three grand. Depending on your perspective though if you figure a multi channel digital EGT is worth at least 1500 then you're only another 1500 for the vibration. I'll look around and see what's available, though. Something conceivably be done with an arduino and an off the shelf sensor too. There are plenty of multi-axis sensors available. We use them for inertial input for drones.

That Insights G3 is pretty cool, and would be the type of thing you would want. I don't think there is anything like that made for what we want to do though. So you would have to make it yourself with a microcontroller (e.g. Arduino, Raspberry Pi, etc.), but at least you could put whatever options/sensors you want in there then.

I don't think the multi-axis sensors will work for vibration. There are several styles, but the most common one basically has a heating element in it and temperature sensors inside the shell that are looking to figure out where the heat is rising to, so they won't measure vibration frequency and amplitude too well. A purpose-built vibration sensor shouldn't be too hard to find though.

For me, the price would have to be contextual to the cost of repairs. Now that I know how these problems go, I doubt I'll ever destroy another engine (which cost several thousand dollars to buy, ship, install, not to mention several dozen hours of labor). Now I plan to get the driveshafts balanced every several thousand miles, and if I break any components mechanically (e.g. cracks, broken off castings, vibrated off/out bolts, etc.) I will immediately check the shafts and u-joints again. In that sense, I'm anticipating a cost of a couple hundred bucks every few years, so for me a monitoring system would need to stay in the neighborhood (or less) than that cost.

 

[aleigh]

"I don't think there is anything like that made for what we want to do" - the insights G3 is made for exactly what we want to do.

I'm glad your happy with your situation, I just wanted to throw out there that these sorts of things exist, and to see if anyone claiming vibration was the root of any of these problems had actually measured to see if that is the case. For my part, I still am not buying the vibration story for my particular case. After all except for the one, all my bolts were nice and tight. And I expect to find destroyed o-rings in my waterpump. But we'll see. I have parts on the way.

 

[Aernan]

A few points:
I built a expanded metal guard for my radiator. It will bolt in with the fan shroud. Cost- about 6 bucks. Radiator-? $1000.00?

could you put up a picture?

 

[Suprman]

The double alt thing is interesting. But the lmtv shares batts between 12 and 24 volt. The niehoff alternator 12 volt output is half of the 24 volt output divided. With 2 separate alternators stacked like that, if you cannot get the regulators to stay exactly in synch with the low being half of the high, then you would need separate battery banks for the 12 and 24. The shared setup would no longer work properly.

 

[aleigh]

Relevant A0 schematics.

 

[NV555]

Sorry I didnt see this post sooner. I live in Ely and could have towed you back with my 1083 or 1078. I have a 200 amp on my 1083 that was on a HMMWV.

2nd item I loved our huge win over your Sea Chickens glad you made it back though.

 

[DOUBLE ALT]

Suprman You are probably correct but. With our setup you separate the batteries. Say two 12 volt connected parellel for the 12 volt and say two 12 volt batts connected in series for the 24 volt side. This works. This also makes it very simple to install and to maintain. You can add more batts. This works and simple.
When ever you center tap the battery bank, you are asking for trouble. One battery will get discharged more than the other.
Anytime you see more than one battery, different manufacture, different date code and more, you are to replace all on that circuit. This helps balance the circuit. I have customers that have had their old alts catch fire. Read the Threads.
I have several out there working and no complaints. We have done testing and found no problems.
We do have a special regulator that is necessary when you run our double alternator as a single output voltage of either 12 or 24. This regulator keeps our double alternator amperage equal between the two outputs.
It is like a twin engine airplane or a twin engine boat that has a automatic prop control to keep the engines synchronized.
People put a 2nd or 3rd and more alternators on a vehicle, thinking they are creating more power. They are creating more trouble, if they do not have a way to control the output/watts of each alternator. If you know anything about alternator regulators, the 1st regulator that has the lowest voltage setting will come on, and the other regulators will stay sleeping until voltage gets to their voltage threshold. That alternator works its but off and after it gets overloaded and can not keep up with demand will a 2nd alt come in to help. This unbalance without a master regulator to control the alts, leads to failures.
Hope I explained it well enough. Double Alt
Picture of one Niehoff that burned the terminal and all wires to regulator.

 

[Adventure Driven]

any way you can send these to me please?

Seth

Relevant A0 schematics.

View attachment 714179View attachment 714178

 

[DOUBLE ALT]

Interested in wiring diagrams
where can I find them
and thanks
Double Alt

 

[Awesomeness]

any way you can send these to me please?

Seth

I'm pretty sure those are just schematics pages out of the back of the TMs.

 

[Adventure Driven]

I so suck at TM's, someone make a u tube video on how to use the darn things LOL

Seth

I'm pretty sure those are just schematics pages out of the back of the TMs.