89 EMERALD 1 GENERATOR KEEPS RUNNING OUT OF GAS

[89 allegro]

i am positive the hose is not kinked and as i said before , i ran i hose 3 ft from the generator to a gas can and the filter still ran low.i have a facet pump now which was what onan told me to get the replace the original ,which still ran just as good as the new one.i have no clue why the filter runs so low and just runs out sometimes.so if it does no difference in 3ft i am sure there no issue back at the tank.it has to be something to do with the filter ,carb ,or fuel pump somehow ,because all the test prove that.

 

[Rob&Deryl]

My $0.02... I would put the filter after the pump so the pump is pushing fuel through the filter.
If it pulling, there is no reason for the filter to fill.
Also, which thing(s) are you trying to protect with the filter? For me, it would be the generator carburetor.

 

[JayArr]

I know that you insist that the hose is not the problem but the specs you posted are for a rubber barrier hose with no inside lining, 30R7 is old school fuel line, it's oil resistant but NOT ethanol resistant. The ethanol that is added to today's gas eats these older rubber hoses from the inside out. It can look brand new on the outside but swell up and close on the inside when the gas starts to flow. This is one of the reasons it is not approved by the coast guard for marine applications. For modern ethanol blended gas you need 30R9 with the elastomer inner liner.

When you connect a new piece of hose directly to the filter and put it in a gas can the genny runs fine but when you connect the three year old piece of 6" hose to the steel line it stops working. It sounds like you've got some new 30R7 so I would replace the three year old sections with new 30R7. If this solves the problem either replace those sections every year or get some 30R9.

ETHANOL

Ethanol is a clean-burning, non-fossil fuel that is produced from a variety of agricultural crops, such as sugarcane and grains. It can be used as an octane-boosting fuel additive or as a stand-alone fuel.

Ethanol fuel mixtures have ?E? numbers which describe the percentage of ethanol fuel in the mixture by volume. For example, E85 is 85 percent anhydrous ethanol and 15 percent gasoline.

The most common blends in the United States are E10, E15 and E85.

While these fuel blends help the environment by reducing pollution and dependence on fossil fuels, they have a negative effect on automotive fuel systems.

Several problems have occurred. One is that ethanol degrades general purpose fuel hose, like SAE 30R6 and SAE 30R7, causing it to deteriorate.

Ethanol adversely impacts the hose, as well as rubber seals and other rubber components, causing it to dry, soften, stretch or crack. Plus, degraded hose particles can contaminate and obstruct fuel injectors, which can affect fuel system monitoring sensors and decrease engine efficiency.

https://www.vehicleservicepros.com/vehicles/powertrain/fuels-and-fueling-systems/article/12044377/modern-fuels-require-modern-fuel-hose

 

[89 allegro]

once again, the filter runs low if its 3 ft hose and pulling from the gas can or hooked to the 20 ft regular fuel line that goes to the tank, the results are the same either way,,, the filter runs low.if you read further down you will see where someone actually looked up my fuel line numbers and said that it was what it is supposed to be for my application.

 

[JayArr]

My mistake, I misunderstood.

 

[89 allegro]

no problem, believe me i wish that was all there was i would be glad to just change the hose. thanks

 

[Charlie 5320]

I just went on Ebay and looked at the RV generators for sale there. Every one of them had the filter before the carb and most were a metal filter. I was thinking my onans all had the filter before the carb after the pump. I have changed some lawn tractors over to electric pumps and most of those had the filter before the pump so I left them that way. Go to Ebay and look for yourself.

 

[89 allegro]

here are some pictures of how my generator fuel line is setup.as you can see theres maybe a inch between the fuel line and the carb, the filters i seen are over a inch around and that fuel line is 1 complete line that goes directly from the fuel pump to the carb and all the books i have show it that same way.i also took pictures of how the filter is and where its placed.

 

[thesameguy]

I think there is supposed to be a filter there...

Looks like this:

https://img.sacsaabs.org/southwind/southwind_gennostart2.jpg

That said, I don't buy for an instant the issue is the filter before the carb. I use the factory Onan filter right before the carb, and a replaceable filter before a Facet pump. That's true on every carb'd car I've ever owed. There's no reason it's a problem.

I really believe either there is an obstruction before the pump (an intermittent one), a leak of some type that's allowing air in, or the pump stops running for whatever reason and fuel siphon/drains back into the tank.

Do I remember correctly you found it could stall out even when running from a gas can?

 

[89 allegro]

it never stopped when running from the gas can but the filter went almost dry just like when running from the tank. if you look at my picture of the fuel line going to the carb, theres no extra room for that metal line to go down to put a filter in there,the metal line sits almost right on top of the engine .so to put a filter there that metal line that came on it would have to go,theres just no clearance for it to go down any further.

 

[Larry N.]

it never stopped when running from the gas can but the filter went almost dry just like when running from the tank.

While I don't know about this specific instance, the (very similar) filter on my garden tractor does exactly as you describe (not full, sometimes looks almost empty) but the tractor runs great, just the same. I think it's designed that way, so long as the fuel actually flows through the filter at the proper rate. How full the filter is is a red herring. That's supported by the fact that your unit keeps running fine from the gas can, so I think you need to chase other factors, as others are saying.

 

[89 allegro]

the crazy part about this deal is sometimes it can run it 2 hours and never cuts off , and other times it want run 20 min till it cuts off and its been like that for the 5 years ive had it. i really dont use it alot unless its hot and were going on a trip,but i mostly go during the winter, nov-april , but sometimes its gets hot during those trips and i really need it.when it cuts off it starts right back up, but im just trying to get it not to cut off.

 

[thesameguy]

it never stopped when running from the gas can but the filter went almost dry just like when running from the tank. if you look at my picture of the fuel line going to the carb, theres no extra room for that metal line to go down to put a filter in there,the metal line sits almost right on top of the engine .so to put a filter there that metal line that came on it would have to go,theres just no clearance for it to go down any further.

Yeah, I get you. It could be a revision between '89 and '93 for sure. Could also be someone fabbed up some fuel tube, but that seems like more trouble than most would go through.

I agree with what Jimmy is saying, that a visual on the filter is a red herring. Even my 7l Cadillac's glass fuel filter is sometimes "low." As long as the bowl stays full, what's happening the filter probably doesn't matter.

Speaking of, have you pulled the bowl out? When I had stalling problems I found my bowl was quite sludged up.

The thing where I'm stuck is that it runs from a gas can reliably, but not the tank. That really calls back to what I was saying - a problem in the feed to the pump, or the pump itself getting shut down.

 

[89 allegro]

i have not pulled the bowl on the carb, that was gonna be my next project because im betting it has never been pulled so if it has alot of sludge in it then it cannot get enough fuel sometimes.now even when it runs from the can the filter gets really low and theres just a slight trickle of gas coming  in to it, but it does the same off the gas tank too, makes no sense ,but I'm thinking its between the filter and the carb is why its not getting enough gas ,but it just seems like it would do it everytime ,not once every 3rd time i run the generator.the bowl pulling will be on the list to try next.i will let yall know how that goes.

 

[Larry N.]

now even when it runs from the can the filter gets really low and theres just a slight trickle of gas coming  in to it, but it does the same off the gas tank too, makes no sense

It makes a bit more sense if you recognize that the filter is probably a red herring, that is, it isn't faulty but is behaving normally. See my comments about that above.

 

[Charlie 5320]

Put the CORRECT fuel filter on it to correct your problems. https://www.ebay.com/itm/Cummins-Onan-Fuel-Filter/283858654951?_trkparms=aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20200818142525%26meid%3D809979e2974c4943aeed76c8f270a697%26pid%3D101195%26rk%3D1%26rkt%3D12%26mehot%3Dco%26sd%3D283858657892%26itm%3D283858654951%26pmt%3D1%26noa%3D0%26pg%3D2047675%26algv%3DSimplAMLv5PairwiseWebWithDarwoV3BBEV2b%26brand%3DCummins&_trksid=p2047675.c101195.m1851

 

[89 allegro]

where would you say im supposed to put it at ? if it goes into the carb, the factory fuel line cannot be used because theres no play in the line ,or in the inlet side of the fuel pump ? like i said before ,my books show that exact metal fuel line ,so ?????

 

[Charlie 5320]

Well if ya can't figure that out after WE have shone ya pics of where ONAN put their filters on later model units. I feel sorry for ya. Done with this thread.

 

[89 allegro]

charlie,,  i have shone ya pics of my generator with the factory metal line on it and no room to add the filter at the carb like you have said that its supposed to go.this is what i have found from onan/cummins below ,thanks charlie for the advice ,but there has never been a filter at my carb.and if there was ,the adapter line is whats on it now..this is what i found on that issue for my generator.and i have not been showed 1 picture of a 1989 generator with the setup like the one i have ,i have seen several like the picture i was sent ,but thats not my setup charlie...

"Your model Onan Generator may have two fuel filters. One underneath the carburetor which you may or may not have because it has since been replaced by an adapter due to this filter leaking fuel into the generator compartment. The second filter should be on the fuel line leading to the fuel pump."

 

[89 allegro]

charlie,,, this is what i found on ebay for a model like mine and i have the exact same setup,,so ya dont have to feel sorry for me after all...

https://www.ebay.com/itm/ONAN-PLUS-6500-GENERATOR-RV-MOTORHOME-GENERATOR-6500-WATT/133557998869?hash=item1f18ad5515:g:1x4AAOSw8vJflzq~