Dirty RV Gas Tank

Zulu · January 4, 2022

I think there's a bunch of sediment in my 20-year-old Sea View's gas tank.

I believe this because since we bought the Sea View, I've been on the Replace-The-RV-Generator-Fuel-Pump about every month.

However, to make sure, I'm going to just replace the fuel filter on my gen's fuel pump in a few days (as soon as the filter gets here).

If I replace the fuel filter and the fuel pump springs back to life, I think I'll have it nailed.

If that's the case . . . How do I get the sediment out of my gas tank (short of replacing the gas tank itself)?

Darryl&Rita · January 4, 2022

If the fuel filter plugs, check the metal portions of the fuel line first. The pickup isn't on the bottom of the tank, where any rust would accumulate.

Kirk W · January 4, 2022

20 minutes ago, Darryl&Rita said:

The pickup isn't on the bottom of the tank, where any rust would accumulate.

As Darryl points out, the fuel suction line for an onboard generator is typically at about 1/4 tank level to prevent running the tank supplying the chassis engine dry. I don't know for sure that yours is that way, but most, if not all were that way by 2000.

oldjohnt · January 4, 2022

If the tank is full of rust n crud it about has to be removed. As far as the fuel pump and clogging, I've (owned RV's fifty years) had fuel lines start to decompose and those particles clog the filter and pump. You may need to run new fuel lines BOTH any old rubber portions as well as steel. Another thing I've done is add yet one more clear in line fuel filter between the tank and genset as they are so easy to see inside and replace if needed. Even though its typical for the genset fuel pickup NOT to reach the tanks bottom (many around 1/4 tank) road driving and bumps and vibration and turns might still possibly get some rust n crud near the genset line pickup area. One hopes a fine mesh screen (if one is on there ???) on the pickup might keep rust n crud out of the line but who knows, hard to say here in the dark ??????????

Ive seen other fuel pump problems caused by excessive flow resistance like pinched smaller sections or too many twists n sharp turns in the line etc. With a long line and especially smaller lines (or any for that matter) any air leaks are a killer...

Problem is some of those lines ESPECIALY at the top of the tank may be hard to get at grrrrrrrrrrrr

Best wishes and Happy New year

John T

Kirk W · January 4, 2022

12 hours ago, Zulu said:

I think there's a bunch of sediment in my 20-year-old Sea View's gas tank.

If that is the problem, why does it only affect the generator and not the chassis fuel system? Since you have a diesel pusher, is it safe to assume that your generator is a diesel that draws fuel from the same tank as your chassis engine? I am quite sure that the chassis has a fuel pump that is in the fuel tank, while your generator probably has the fuel pump mounted on it's engine. If I am right then it seems to me that the problem is much more likely to be a restriction in the fuel lines between the generator and the fuel tank.

oldjohnt · January 4, 2022

46 minutes ago, Kirk W said:

I am quite sure that the chassis has a fuel pump that is in the fuel tank, while your generator probably has the fuel pump mounted on it's engine.

I would guess that to be true ???? (but not being there or armed with a manual or info I cant say) based on the many Ive seen or owned or sold. Its been yearsssssssssss that electric fuel pumps have been located inside the tank and of the dozens and dozens of onboard RV gensets Ive seen or owned indeed the elec fuel pumps are on the generator. Its back to a line restriction (pinch off or too sharp kinking bend) or a steel line is rusting and Ive seen old rubber lines harden up and start to deteriorate with small black particles clogging a filter or pump. Replace lines and add one more clear inline filter may be one solution ?????????

LET US ALL KNOW WHAT YOU FIND

Happy New Year

John T

Lou Schneider · January 5, 2022

Is this a gas or diesel generator/motorhome? When I was taking care of radio stations, our 50,000 watt transmitter had a 210 Kw Caterpillar genset fed from a 5000 gallon diesel tank (it was an all news station, in the event of a major disaster the company wanted the ability to to stay on the air at least a couple of weeks without refueling). Once a year we would have a company come out and "polish" the fuel in the tank to remove sediment, water and algae. This consisted of pumping the fuel through a series of filters starting at 2 microns and finishing up at 0.5 microns.

Something that's often overlooked in an RV installation is the generator has to suck fuel out of the top of the tank, similar to drinking through a straw. The in-tank fuel pump only feeds the main engine. This is so if there's a break in the line running to the generator the line will break suction instead of letting the tank continue to drain. A hairline crack in any of the rubber hoses will introduce air into the fuel, this may not be a problem with a new tank and a fresh filter but may interrupt enough fuel flow to starve the engine as the filter becomes plugged or the pump wears.

Kirk W · January 5, 2022

59 minutes ago, Lou Schneider said:

Is this a gas or diesel generator/motorhome?

Quote

Full-Timing / 2001 Newmar Mountain Aire DP 4095

From his signature.

Darryl&Rita · January 5, 2022

1 hour ago, Kirk W said:

From his signature.

Signatures don't show up on all phones.

GlennWest · January 5, 2022

6 minutes ago, Darryl&Rita said:

Signatures don't show up on all phones.

noticed that also

Kirk W · January 5, 2022

58 minutes ago, Darryl&Rita said:

Signatures don't show up on all phones.

And you can set it to not show signatures on your computer, but it s still in the signature, even if you don't look at it.

Edited January 5, 2022 by Kirk W

durangodon · January 5, 2022

11 hours ago, Kirk W said:

From his signature.

This is what I see in his signature SKP #79313 / Full-Timing / 2001 National RV Sea View / 2008 Jeep Wrangler Rubicon

Kirk W · January 5, 2022

4 hours ago, durangodon said:

This is what I see in his signature SKP #79313 / Full-Timing / 2001 National RV Sea View / 2008 Jeep Wrangler Rubicon

That is what is there now but Zulu went in and edited his signature as what I posted was a cut/paste form the signature that was showing at that time. Hmmmm.....??? 😏

My guess is that he had changed RVs and only just now changed his signature, which does mean he has a gasoline coach, now. How about it Zulu, did you edit your signature since your first post?

Edited January 5, 2022 by Kirk W

Zulu · January 15, 2022

About my "dirty" gas tank . . .

I know RV gens are supposed to stop when the RV's gas tank gets low. But how low?

On my former RV (a 2001 Newmar DP, Kirk), that was 1/4 tank. If the tank level dropped below that, my generator would stop.

Apparently, the generator on my current RV (a 2001 National RV Sea View), is set to stop at a much higher level -- maybe 3/4 full.

To test this, I filled my RV's gas tank and tried starting the generator in the gas station. The generator started and ran just fine. I left it running on the way home (about 10 miles away). However, on the way home we went down a steep hill and the generator stopped.

So it looks like someone ran a new fuel line from the generator to the gas tank, but didn't insert the line very far into the tank.

Well, at least it only took 3 generator fuel pump replacements.

Kirk W · January 15, 2022

10 hours ago, Zulu said:

On my former RV (a 2001 Newmar DP, Kirk), that was 1/4 tank. If the tank level dropped below that, my generator would stop.

Apparently, the generator on my current RV (a 2001 National RV Sea View), is set to stop at a much higher level -- maybe 3/4 full.

That is Zulu for saying that he did change his signature after he started the thread, or of avoiding the admission. 😉