Big Cam Cummins reliability

A service manual doesn't give you the feel of experience. There are so many scenarios that dont play out in the diagnostic flow chart in the manual.

 

There really is a growing number of mechanics of all kinds that really are just parts-changers.

 

How are they simpler than a modern engine? What makes them simple? You have my curiosity up....... simply asking.

 

Well you've got about a hundred fewer ground spots to cause issues that are hard to find, just to start.

 

Well I had someone that is a mechanic guide me through the repairs on my Big Cam. I have learned more about these engines than I ever thought there was to know. And there is probably that much more that I do not know.

But I am not a mechanic that earns a living as a mechanic.

I agree with this. I think that what I'm trying to say is that if you need the overhead set or if you needed something like a set of bearings, an experienced mechanic should be able to do that with a shop manual. And I think that if the engine had a problem like a bad injector or a bad head gasket a professional mechanic should be able to figure that out if he understands the fundamentals of how an engine operates.

But I do agree that experience with whatever particular engine does make pinpointing the problem quicker.

What I mean by that is that the mechanical engine is much simpler. If there is a problem it is purely a mechanical problem.

Here's an example. Has anyone read the thread for truck 306? I think that he spent somewhere around $25,000 trying to figure out what the problem was with his electronic engine.

The truck had been to countless dealers that specialize in that engine. It was still under warranty and no one could tell if he had an electronic problem or a mechanical problem. It was a nightmare. He even had big shots from Caterpillar ride with him in the truck and no one could figure it out. They replaced part after part and did test after test and it was an ongoing problem for quite some time. That would not have happened if it was a mechanical engine.

The mechanical engine is much simpler because there are no electronic systems to diagnose. There is no multitude of sensors and wires and computers to make the engine run or not run. There is no computer controlled turbo or injectors or timing. There are no electrical systems or sensors that will make the engine run funny or shutdown. And that is not even touching on the emissions systems.

The mechanical engine only needs fuel, air, and compression to run. If you can turn it over or push it down a hill, it will run on its own as long as you keep fuel in it.

If an electronic engine won't start... Is it a fuel problem? Is it an engine problem? Is it a power wire? Is it the computer? Is it one of the many grounds? Is there a sensor somewhere telling the engine not to run? Is it a fuse somewhere? It is all very complicated. But the Big Cam is very simple.

So basically what I'm saying is that the electronic engine is the same mechanical engine underneath with all kinds of complicated nonsense that causes additional problems, costs more money, and is more difficult to diagnose.

Definitely the Big Cam is much simpler.

 

There is one wire on a big cam that will shut the thing down, eliminate that and it can only be a mechanical problem and it will actually be possible to fix by changing parts.

 

The problem is how to think is a lost skill. Diagnosing a problem requires the ability to think. Modern mechanics rely on the engine code to think for them.

 

Are you talking about the wire to the Fuel Shutoff ??

 

Bought my first truck in 1974, NTC335, I overhauled it once. Bought a new IH NTC350 SC in 1977. Ran that engine, until 1996,I overhauled it 3 times, 400k to 500k normal overhaul levels back then. Cost me less than $2k for an overhaul. Next, bought a IH with an N-14 500, then ran it 20 years until I retired, never had the engine apart. Best moneymaking engine I ever owned. Some sensors and a computer, slightly challenging, but that was mainly the reason for that engines longevity.
These engines were easily overhauled and understood, if you had any kind of mechanical aptitude. Get a service manual, good set of tools, and be able to read and understand a mic. I would overhaul mine on a weekend, just make sure your counterbores were good, sleeves set correctly, the rest is just abc's.
In 42 years with my own truck and trailer, the number of times I was forced to put my truck in someone else's garage and pay for a repair, I could count on one hand. Good common sense maintenance, and understanding what you own goes a long way. If someone else could do it, there was no reason why I couldn't.

 

Yea, that's the only wire that I know of that'll shut them down.