Common Rail Diesels - Experience

[Compass790]

Originally Posted by Shaneesprit

Don’t think your engine is common rail
That’s the whole point of this thread - the Mechanical injectors can recover even the Hydraulic pressured Electronic Unit injectors Can cope or be recovered from a dash of water - Common rail engines cannot!
2000 - 3000 PSI pressure in the injector is standard diésel.

Yes I made it clear that my engine was not a common rail when i described it as an IDI engine. IDI stands for indirect injection that is the engine has a pre-combustion chamber. No pre-copm chamber equipped diesels are common rail AFAIK
Yes I was just re-inforcing the idea that a mechanical injection engine with 2400 psi can cope with water from recent experience unlike a common rail to point out one of the disadvantages of a common rail.
Not that you want any water in a mechanical injection diesel either.
Seems I wasnt clear enough.

[pbdayger]

Ha….forget all the complication with the Common Rail…..go simple and burn Biodiesel….you’ll be happy to have a clean burning engine….80+5 less Co2….you’ll be doing your part for your grandchildren!!! Will smell better going down wind too!!

[Dieseldude]

Originally Posted by Compass790

Yes I made it clear that my engine was not a common rail when i described it as an IDI engine. IDI stands for indirect injection that is the engine has a pre-combustion chamber. No pre-copm chamber equipped diesels are common rail AFAIK
Yes I was just re-inforcing the idea that a mechanical injection engine with 2400 psi can cope with water from recent experience unlike a common rail to point out one of the disadvantages of a common rail.
Not that you want any water in a mechanical injection diesel either.
Seems I wasnt clear enough.

Yup, shows another weakness of electronically controlled common rail, and strength of mechanical injection. Water in fuel is certainly a hazard that cannot be completely eliminated. Water can still make its way to the engine despite all the care one takes such as frequently draining the fuel tank or keeping water block filters. Also, fuel quality in some areas of the world is not so good as we are accustomed to in industrialized countries. Water and dirt can be more common in such places, and common rail systems are much more vulnerable than mechanical injection.

[RaymondR]

How many sensors do they generally have in a common rail system and what so they do?

I have had two Volvo cars which provided about forty cumulative years of operating experience which had electronic controlled fuel injection systems which were without a single problem for the entire time. I believe these had Bosch electronics and from this experience it appears that auto electronic systems can be extremely reliable.

I also also had a Ford company car for about six years which used to eat brake pads because they could not get it to idle properly and have a Ford diesel van which has a habit of shutting itself down if I get too cavalier on the throttle. Since I bought it from a Ford dealer and it had the problem when I bought it I assume that like the company car the problem is probably unfixable, or too expensive to fix, and consequently I infer from these experiences that design and build quality has a big impact on the reliability of electronically controlled fuel systems.

[bcboomer]

As others have said, it's the water contamination and fuel cleanliness that are the likeliest failure points.

[Notfast]

I dont know why anyone would repower with a common rail equipped engine, as others have mentioned, any problem with the ECU and you're effectively engineless.

I just repowered with a new Beta Marine 25 hp naturally aspirated engine with fully mechanical fuel delivery and a much much larger support network not only from Beta Marine but also Kubota, I think Beta engines go up to 120 hp with turbocharged options. Why wouldn't you choose a Beta? Their finishing (engine paint) is poor but what's underneath has a great reputation and is cheaper than a Yanmar.

[Dieseldude]

Originally Posted by RaymondR

How many sensors do they generally have in a common rail system and what so they do?

I have had two Volvo cars which provided about forty cumulative years of operating experience which had electronic controlled fuel injection systems which were without a single problem for the entire time. I believe these had Bosch electronics and from this experience it appears that auto electronic systems can be extremely reliable.

I also also had a Ford company car for about six years which used to eat brake pads because they could not get it to idle properly and have a Ford diesel van which has a habit of shutting itself down if I get too cavalier on the throttle. Since I bought it from a Ford dealer and it had the problem when I bought it I assume that like the company car the problem is probably unfixable, or too expensive to fix, and consequently I infer from these experiences that design and build quality has a big impact on the reliability of electronically controlled fuel systems.

Great that you beat the odds with your Volvos. But if you'd been unlucky, the cars would have become scrap metal at an early age. Just get a blown computer that could cost several thousand dollars on say a seven year old car, and decide if you sell it to a wrecker for a hundred bucks, or throw good money after bad on a new computer. Carburetors were finicky things, but they were repairable, or at worst replacing one was not nearly as costly as a computer that controls injectors.


As for the Ford car and van, these are just more examples of electronic cans of worms.

[bcboomer]

I worked in a Dodge truck dealership when common rail came out. There were some teething issues with throttle sensors that left a few loggers stuck coming out of the bush at an idle and fuel pump problems caused by the fuel suppliers but never an issue with the computers themselves. That said, I wouldn't put one in a boat "just in case".

[Bill Seal]

Virtually all gas powered cars today are EFI, and run less than 100 psi on the rail If the ECU takes a dump, you can get a rebuilt one from a factory authorized rebuilder for a few hundred bucks.
30,000 psi common rail diesels are a different animal altogether.

[Dieseldude]

Originally Posted by Notfast

I dont know why anyone would repower with a common rail equipped engine, as others have mentioned, any problem with the ECU and you're effectively engineless.

I just repowered with a new Beta Marine 25 hp naturally aspirated engine with fully mechanical fuel delivery and a much much larger support network not only from Beta Marine but also Kubota, I think Beta engines go up to 120 hp with turbocharged options. Why wouldn't you choose a Beta? Their finishing (engine paint) is poor but what's underneath has a great reputation and is cheaper than a Yanmar.

The big weakness of central control systems is that they are central control systems. When they fail, nothing else works either. Independent mechanical injection is much more rugged.