MEP-003a Fuel Line Question

[54M37]

Recently purchased a 10K generator and am going over it. Fuel tank was a mess; full of rust and crud, but I couldn't believe how clean the strainers and filters were. Noticed that the fuel suction in the tank is about an 1" off the bottom of the tank; guess that's why the pumps didn't suck up all the crap from tank. The diesel fuel must have been really old as it smelled more like paint thinner than diesel.

My question concerns the fuel supply line to the injection pump. The line that runs from the block at the generator end of the engine to the injection pump. Is this a metal line or rubber hose? Couldn't find a good picture in my manual and the one on the generator is now a piece of rubber hose held on with hose clamps.

Also fuel fittings look to be JIC 37 degree flare fittings; is this correct?

Thanks for any help.

 

[Isaac-1]

I would have to look at mine which is 30 miles away at the moment, but I think the lines in that area are a combination of metal and rubber lines, most of the fittings in the fuel system are AN fittings which is thread compatible with JIC (for practical purposes JIC and AN are interchangeable, but AN threads are slightly different, rounded vs pointed, I think to allow better alignment and greater number of reconnections, as well as being stronger and handle vibration better)

 

[dependable]

Like Isaac said, a flex line with metal fittings. Looks a lot like the lines between the fuel filters but has a 45 degree bend fitting at IP end.

 

[54M37]

Yes; I got a hold of the parts manual for the MEP and the fuel line I asked about is shown in one of the pictures as a hose not a metal line. That makes sense since the IP is on the engine and the block is on the frame; vibration may be a problem with a metal line.

 

[rustystud]

All the fuel lines on a MEP-003A and MEP-002A are flexible rubber. The line to the injection pump also has a one-way check valve in it. The only hard line is the fuel tank suction line.

 

[JimH]

It is typical to find crud and rust at the bottom of the fuel tank. Obviously, it will need to be cleaned out. The fuel lines are 1/4" ID rubber (nitrile, I think) with JIC fittings. I am in the process of replacing all of mine, as I have a problem with the fuel coming back on the return line is black from a deteriorating line somewhere. It is a good idea to run some kind of cleaner through the fuel system, Sea foam or Diesel Kleen or similar) to clean the system out, and loosen any stuck parts prior to trying to start. I was doing that when I noticed the problem I have. The check valve has a tendency to gum up as well. Good Luck, you are on the right track.

 

[54M37]

Where is the check valve you mentioned located?

 

[Isaac-1]

JimH, are you running bio-diesel or a bio-diesel blend?

 

[JimH]

The check valve is located between the second fuel filter and the IP. It is held in place by a metal strap to the motor. It looks like a union between the two hoses. I run ULSD diesel with some Dextron ATF as a lube substitute for the sulphur.
I am not aware of anyone using Bio-Diesel on these units. I am not saying no one is doing it, just that I am unaware of anyone.

 

[54M37]

Yes; I saw the check valve exactly where you mentioned. I thought it was a union of sorts.

There is a study floating around the internet that compares different additives to ULSD with the old high sulphur diesel. Acording to the study ATF does not do much to improve lubricity. I will search and see if I can find the study.

http://www.dieselplace.com/forum/76.../177728-lubricity-additive-study-results.html

I have been using the Opti-lube XPD in my tractors and Dodge pickup. Around here off road diesel and #2 heating oil are also ultra-low same as undyed on road diesel.

ATF must have been in another study I read. I believe the AFT is not designed to burn and can leave deposits on the valves and combustion chamber.

 

[rustystud]

Yes; I saw the check valve exactly where you mentioned. I thought it was a union of sorts.

There is a study floating around the internet that compares different additives to ULSD with the old high sulphur diesel. Acording to the study ATF does not do much to improve lubricity. I will search and see if I can find the study.

http://www.dieselplace.com/forum/76.../177728-lubricity-additive-study-results.html

I have been using the Opti-lube XPD in my tractors and Dodge pickup. Around here off road diesel and #2 heating oil are also ultra-low same as undyed on road diesel.

ATF must have been in another study I read. I believe the AFT is not designed to burn and can leave deposits on the valves and combustion chamber.

I'm also using the "Opti-Lube XPD" . Great stuff.

 

[steelypip]

The study I saw gave highest lubricity marks to adding 10% B-100 (biodiesel) to your ULSD. It was also the cheapest option. With the biological aspect, you'd want to mix in some biocide for sure.

 

[Ray70]

A few years ago I was making biodiesel to run in my backhoe and Lull, but didn't have the MEP's at the time so I never used it in one, but from my other experience I can talk about it a little.
Biodiesel is an excellent detergent and lubricant. It will loosen and clean off pretty much anything in your fuel system. The only down side to this is you need to ensure that anything it loosens gets trapped in the filters and doesn't get through to the IP and injectors. The other problem is that Biodiesel will eat (soften) many kinds of black rubber like fuel lines, seals etc. so you might have an issue over time with it deteriorating the rubber fuel lines on the MEP. also, if there are seals in the IP that come in contact with the fuel, they may also be at risk. Biodiesel also has a slightly lower BTU content so when running straight Bio, you might see a power loss. Most of these problems can be solved by simply running a blended fuel at a B-20 or lower percentage. B-10 should be fine in most all cases. Biodiesel also clouds at around 35 degrees or so, so be careful if using a high percentage in colder climates.
The other down side to running biodiesel is that if you're around the exhaust fumes too long you'll start getting the munchies

 

[glcaines]

A friend of mine was running biodiesel in his almost new New Holland tractor. It worked great until it ate up some of the fuel lines and disabled his IP with particles. The New Holland dealer told him never to run biodiesel in a NH tractor.

 

[lxawolf]

Bio diesel is a much more powerful solvent than petro diesel. It will clean up your fuel system, it will remove much of the crud in the tank, lines ect. One thing I have learned from the heating oil industry is a gradual phase in of the Bio based product. Often they will start with a B5 solution moving to B10 on the next tank. This will include a change in filter material with each increase in percentage. The gradual phase in is helpful to minimize the clogging properties of the freed partials. As others have stated that some older rubber and plastics are not comparable. Some can breakdown. Most modern engines are now required to tolerate a B5 to B20 range. Bio based fuel also has a much shorter life. Due to this it's not recommended for long term storage. As it can biodegrade, (this can have many factors that are almost impossible todetermine due to so many different factors).

 

[rustystud]

Bio diesel is a much more powerful solvent than petro diesel. It will clean up your fuel system, it will remove much of the crud in the tank, lines ect. One thing I have learned from the heating oil industry is a gradual phase in of the Bio based product. Often they will start with a B5 solution moving to B10 on the next tank. This will include a change in filter material with each increase in percentage. The gradual phase in is helpful to minimize the clogging properties of the freed partials. As others have stated that some older rubber and plastics are not comparable. Some can breakdown. Most modern engines are now required to tolerate a B5 to B20 range. Bio based fuel also has a much shorter life. Due to this it's not recommended for long term storage. As it can biodegrade, (this can have many factors that are almost impossible todetermine due to so many different factors).

The transit agency I work for played around with Bio-Diesel awhile ago. We went through so many injection pumps it was ridiculous ! We started to rebuild the pumps with different seals (I believe they where Viton ) and that solved the problem, but they decided to stop using Bio-Diesel anyway. We also started to use the Poly hoses with the Stainless Steel sheaves (outside Liner).