Diesel fuel distribution and oil filtration system?

[DavidWymore]

Here's a good visual.

http://youtu.be/ujokaEkF8Z0

 

[DavidWymore]

Diesel trucks as built seem to work fine...but it seems they can work a little better. I wouldn't spend several hundred dollars to buy a kit to remove air, but if I can do it myself on the cheap, it would be a fun and interesting project.

I read somewhere that diesel engines and components when run on a test stand get their fuel from a large undisturbed tank of fuel about 10' away/above and the returned fuel with air goes into a separate tank. So, kinda like on a dyno, on a test stand, conditions are perfect. Not so much in a truck bouncing down the road.

 

[DavidWymore]

I emailed FASS and asked about making my own tee vs. buying theirs and got a rude reply, but there are a couple nuggets in this article. Dirty fuel filters don't just starve your engine for fuel, they cause it to suck air, which is probably the cause of a lot of the bucking and surging, etc. when filters get plugged.


http://www.fassride.com/tinymce/filemanager/files/MovinOutCondensedArticle.pdf

Owner of FASS is son of owner of AirDog, who is the orginator of the preparator. If I was going to buy anything, I'd go with 'dog after the rude email I got from FASS, nevermind that they say all their stuff is made in USA.

 

[Jeepsinker]

That system was developed to deal with problems inherent in the design of the bosch VP44 injector pump. Our pumps are completely different and don't suffer at all from the problems that system was meant to address. Our pumps are much more robust, just keep particulate matter out of them.

In other words, it would be a waste of time and would likely actually cause issues rather than fix them. It was an interesting thought though.

 

[red]

I wouldn't call the IP on the multifuel robust by any means

 

[Jeepsinker]

I said more robust.... and our pumps really aren't weak. They put up with a lot of abuse and neglect before they actually need replacement.

 

[DavidWymore]

Didn't some of the Cummins trucks pull/suck the fuel from the tank and later pumps push with an in-tank pump, like the deuce? Seems like vacuum is an issue...

 

[red]

Most of the light duty (3/4 and 1 ton) diesels don't run a lift pump from the factory.

I've never messed with the Airdog system, but the improvement of installing any type of lift pump on a diesel is noticeable. Extends the life span of the injection pump. However, unless you get a multifuel to survive for over 100,000 miles, I would not say an air separator is worth the expense.

 

[Jeepsinker]

All the dodges have run lift electric lift pumps since late 1998. First was a block mounted electric pump, which was prone to dropping fuel pressure and damaging the piston in the injector pump. Dodge then came out with a retrofit to an in tank pump to fix the problem. All the newer dodges are the same, I did many retrofits on new trucks when I worked at the dealership.

 

[rustystud]

I wouldn't call the IP on the multifuel robust by any means

As compared to the Cummins which if you sneeze wrong will seize the piston up. Our injection pumps are pretty good units as long as you keep the crap out of them. We have about 600 busses running Cummins in them ( ISC, ISB and every other stupid number) and I would never own one after all the crap these injection pumps put us through. You can never fill the secondary filter before installing it since a 2 micron particle will damage it. You always use the electrical and mechanical pumps on the engine to fill the filters, which go through the primary filters first.

 

[red]

True they are not as picky about filtration, but with such a short lifespan I can't view them as a good injection pump. HH issues, buttons falling off, the known fuel shutoff issues, mixing fuel into the engine oil, all common problems that develop with less than 40k miles. Most other models of injection pumps don't need to be opened up for repair until over 150k miles. They are versatile and easy to work on, but not robust.

I forgot that dodge runs a stock lift pump.

 

[Jeepsinker]

All of those problems are attributed to sitting for long periods of time, not poor design. Once the problems are addressed, which only takes about an hour, they are a long lasting pump. The biggest killer of them is rusty fuel tanks putting fine rust particles through subpar factory filters and eating the hydraulic head up. I know some guys have had terrible luck with them, but think of how many are still out there running every day after the better part of 50 years.

 

[rustystud]

All of those problems are attributed to sitting for long periods of time, not poor design. Once the problems are addressed, which only takes about an hour, they are a long lasting pump. The biggest killer of them is rusty fuel tanks putting fine rust particles through subpar factory filters and eating the hydraulic head up. I know some guys have had terrible luck with them, but think of how many are still out there running every day after the better part of 50 years.

That's right Garret ! When I was still in the Marines, we would run these trucks ragged and they would take it and say "is that all you got ? !!! " You let any piece of equipment set for long periods of time and you will get some major issues very soon. Especially something as highly machined as an injection pump. Lets see what happens to one of these NEW injection pumps after setting for a year or 10 ! My friends 1 ton Ford with a 7.2 IHC engine has set for just one year now and we tried to get it to run last week and the stupid thing will not even pump out any fuel at all ! I had warned him to start it up at least once a week but he didn't think that was necessary.

 

[JasonS]

I got 62k miles on my dodge before I had to replace the VP44. At least it was easy to replace. I think that the Bosh/ Multi works VERY well together (starting and running).