MEP 803A Corrosion On Fuel Fill Components

[Dave926]

I noticed my fuel gauge ran up past full when I ran it last and then went below empty and stayed there. Checked the resistance, none there. Open circuit right at the sensor. Tried to take out the sensor but it fell apart when I removed the top flange. I figure I can reach in from the filler spout and pull it out the rest.. I'll have to take out the spout and the fill flange. I noticed some serious corrosion on both the filler spout and the flange that wasn't there when I bought it about a year ago. It was manufactured in 2012 and rebuilt some there after. Had 2 hours on it. It looked brand new. Everything else is flawless. I bought diesel from a regular pump at a gas station and filled it up several months ago. Maybe this is a result of bio-diesel? I did not notice anything at the pump mentioning a blend with bio-diesel. I put nothing else in the tank.

I bought the replacement sender mentioned in another post that uses hall effect magnets instead of the swing arm. Got the 8.5 inch version. I stuck a dowel rod down the sender hole. Although it's close, I think it will clear the drop down side of the tank without the spacer. What kind of plastic will survive in the diesel tank? Does anyone have a picture of the plastic piece on the sender? I'll let you know when I get there. Has anyone who has installed these had to take the tank out first? The 8.5" may not make it due to the lack of overhead clearance.

As long as I have this apart, I was going to replace the aux fuel filter. I have the parts manual but could not locate it on the diagram. Does anyone know the replacement aux fuel filter number?

 

[Zed254]

I noticed similar rust on my 802 fuel spout and hit it with WD40. Also, the fuel side of the tank cap.

Daybreak has done an excellent job of recording most of the filters and maint. components you will need here: https://www.steelsoldiers.com/showthread.php?186068-MEP-802A-MEP-803A-Filters-and-Parts

Airtex G-17 is the inline filter for the primary fuel pump.

Here is info from TM for Aux fuel pump filter

21 PAOZZ PAOZZ PAOZZ 30554 88-22755 .FILTER BODY, FLUID 1

And Partarget will list the various model numbers: https://www.parttarget.com/2940-01-...&searchoption=sku&originalsearchtext=88-22755

Wix 33046, Baldwin GF27

 

[Bmxenbrett]

You can remove rust with a old school battery charger and pool PH plus. I have done it to resurect a $50 generator with a badly rusted metal fuel tank.

No doubt that at one point your tank has had moisture or water in the tank. If you havnt i would change the fuel filters and clean the pump screens at the fuel pump.

 

[Chainbreaker]

You can remove rust with a old school battery charger and pool PH plus. I have done it to resurect a $50 generator with a badly rusted metal fuel tank.

OK, so I have an old school battery charger and perhaps can find pool PH plus at Wall Mart or the like. So what is the process...what am I hooking up the battery charger too and what is the dilution of PH Pool plus? Details please...

 

[Chainbreaker]

I noticed some serious corrosion on both the filler spout and the flange that wasn't there when I bought it about a year ago. It was manufactured in 2012 and rebuilt some there after. Had 2 hours on it. It looked brand new. Everything else is flawless. I bought diesel from a regular pump at a gas station and filled it up several months ago. Maybe this is a result of bio-diesel? I did not notice anything at the pump mentioning a blend with bio-diesel. I put nothing else in the tank.



View attachment 773051View attachment 773052

Yes, the rust you are experiencing on the fuel fill/strainer is very common. See it on all 3 of my gensets. I believe it is attributed to BioDiesel content and its hydroscopic nature. Not sure what the strainer is plated with but Biodiesel does react with certain metals and may be eating off the plating and then the moisture carried in the BioDiesel starts the rusting process. In most states you won't see any Bio-D labels on pumps that have 5% or less. I think that is due to Federal labeling requirements, which seems to change now and then regarding Alternative Fuels dispenser labeling.

 

[Bmxenbrett]

Just google "rust removal useing a battery charger"

Basicly your reverse plating the parts with a sacrificial piece of metal. It worked very well on the inside of my metal gas tank. Before it would clog the pickup screen in 10min run time.

 

[Dave926]

The coating on the metal pieces is pretty significant on the filler spout/screen and the bracket it slides into. I am concerned that this will contaminate the fuel if it hasn't already. I was considering removing the bracket and cutting of the metal of the bracket that sits in the tank. Taking out the fuel tank looks like a major job.
I also don't know what the bio-diesel is doing to the components downstream, pump, injectors filters, etc. Just think it's funny the sensor died around the same time I noticed the corrosion.
On a good note, the new fuel sensor went in fairly well after I figured out how to get the old one out after considering sticking my hand in and pulling out through the fuel filler port. I just cut the wire, let if fall to the bottom of the tank. I have a 2' flexible rod with a magnet on the end. Pulled it right out. Fuel smelled like turpentine and the sensor was rusted and coated in a slimy brown goo.

 

[Dave926]

I ended up removing both metal pieces after removing the top piece over the radiator. The hardest part was trying to separate the exhaust pieces after they were clamped together and run a few times. I didn’t’ have a torch so in desperation, I used a heat gun. Didn’t this would work but it did.
I cleaned out the tank. There was tons of rusty goo coating the bottom of the tank, sides and even green goo on the top. I used paper towels soaked in fresh diesel to clean. Went through a whole roll.
From what I could see, the remaining piesces (pickup and aux fuel sender) were either stainless or aluminum. The only thing that worries me is that the I could feel a putty like substance around the fuel tank drain. Didn’t seem to hurting anything so I left it alone. The new sender I put in does not feel like it comes to close to the side of the tank. Feels like an 1.5” left from the botttom of the new sender and the bottom of the tank. Could maybe have put in a 9”. Put it all back together and runs great.

 

[Zed254]

....The only thing that worries me is that the I could feel a putty like substance around the fuel tank drain. Didn’t seem to hurting anything so I left it alone.

The putty like substance may be your well nut failing. I've read the JP-8 used in these generators is rough on the well nut. I replaced both of mine in my 802 - see picture. There are 2 ways to replace the well nut......

https://www.steelsoldiers.com/showthread.php?154411-The-infamous-Well-Nut-info&p=1875261#post1875261

https://www.steelsoldiers.com/showthread.php?171091-Ultimate-well-nut-repair&highlight=

 

[Dave926]

Thank you all for the great comments. I ordered the new parts this morning per Boatman69. He lives right around the corner. Would be great to compare notes.

 

[Light in the Dark]

You WILL thank yourself by replacing the well nut right now on the tank, while you have it drained and ready. Get the brass upgrade and NEVER think about it again.

 

[csheath]

This caused me to go check mine. It has a slight gray film on the outer casing The the screen is rust colored but not clogged or disintegrated. It looks like the screen housing is coated with galvanize coating. This is no longer acceptable in the diesel world.

According to my fuel supplier pure diesel is no longer available. He says it's all 5% bio diesel for unlabeled and the labeled bio diesel I've seen around here says it's 15%.

I was under the impression that bio diesel was just mixed with recycled cooking oil but i admit I haven't researched it. Degradation of the galvanized finish may indicate it has some ethanol in it however coating anything with galvanized coating is now considered a no no for diesel fuel. Even my tractor manuals say to never put diesel fuel in a galvanized container.

Back in the 80s when they first introduced ethanol gasoline mix we saw the fuel eat away the galvanized coating on the inside of gas tanks. One of the changes that had to be made to make vehicles ethanol compatible was different tank coatings or plastic tanks. Back in the 80s I could dump a Bosch fuel filter inlet side down into a clear jar after a vehicle had used ethanol fuel for a while and it would come out cloudy gray colored. After the fuel settled for a while it would be clear fuel on top and a layer of gray paste in the bottom. I am talking two inches thick on the bottom of a coffee jar.

 

[Dave926]

That's what I had all over the metal parts that touched the fuel, gooey gray paste. I ordered the new brass fittings this morning. Should have before the weekend and installed before Doria gets here. Went two weeks without power during Irma. Not doing that again. Smelled like a signal 7 when I was finally able to get back home. All the food spoiled in the freezer and fridge.

 

[csheath]

After some thought and inspection I have decided to remove the strainer basket from my fuel filler. Article after article tells you that diesel fuel can dissolve the zinc in galvanized coatings. Both of my tractor manuals warns against the use of galvanized cans for fuel storage.

Yet the strainer basket and fuel filler neck in our generators is clearly galvanized coated. Mine looked to be in good shape when I put it in service but now it has signs of degrading. I have kept the tank full of treated off road diesel and my storage drums with the same treated fuel still look okay.

Removing the basket will at least limit the amount of submerged coated metal.

A while back I replaced my pump strainer with a small engine fuel filter. I'm talking about the little metal fuel filter screwed onto the fuel pump inlet. I caught some flack about using the paper type filter instead of the nylon screen type but I have used these on ALL my diesel equipment with good results. The explanation from the manufacturer said the paper in the small engine filter was not coated like the same paper used in the diesel filters. They said the uncoated paper may absorb water and clog. In my way of thinking this was a win. If my system gets water in it and clogs the filter in front of the pump and water separator it just gives me early warning of the problem.

At any rate I have a plastic type strainer on the fuel pickup tube I use to pump my diesel into the machine. Between that and the clear filter I put in front of the pump I don't see a need for the strainer in the filler basket.

If I could find a plastic replacement for the fuel filler neck I would replace that. So far the coated surfaces of that still look okay.

 

[Cbacres]

I just cleaned my tank on my 803a tonight. It was a brownish rust color stiff goop.i dumped some CRC tank renew in tank with just a little fuel left in bottom of tank.
I had to scrape the bottom with a plastic putty knife to get it broke up. I scrubbed every square inch of the tank with a rag soaked with this treatment. I’ll flush and drain tomorrow with a little fuel.

I was just doing a basic service when I also noticed the fill strainer had rust and a heavy dose of this goop.

Mine unit is a 2007 with 14 hrs, bought early last year. It was full of red fuel, it’s clean, I just figuired the goop was dried residue from fuel back in 2007 when it was stored.

My gauge also stopped working, pulled it and I’m replacing with a stainless straight type, I ordered a 9-1/2”, tank is 10”.

I’m also replacing the well nuts on return and drain.