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Fuel Filters [message #327917] Sat, 06 January 2018 16:59 Go to next message
Carl S. is currently offline  Carl S.   United States
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
Senior Member

I have been fighting fuel starvation issues for years, so I try to keep up with maintenance to help my fuel system be the best it can be. Today I replaced the two in line filters under the coach and the carb inlet filter on the Q-jet.

After replacing the filters, I cut one of the in-line filters and the car inlet filter open to have a look at the elements. Both of the in-line filters appeared to be free flowing and no dirt came out of them when I blew them out into a rag. The carb filter had the slightest amount of very fine grit in the pleats, but it didn't seem excessively dirty.

I don't remember when I last replaced these filters, but I'm sure the carb filter, at least was replaced less than 8000 miles ago.

How often do you guys replace fuel filters and what do you use as a criteria for when to replace them. They are cheap, but not quick and easy to replace, making me reluctant to waste any more time on them than absolutely necessary.


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: [GMCnet] Fuel Filters [message #327920 is a reply to message #327917] Sat, 06 January 2018 17:54 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
It is not the particullates that is restricting the flow but the gum that
the ethanol is washing off ALL sides and top of the tank.
Just replace them all and go for another 10,000 miles.
It will get better and will not have problems later.
Be sure to run down the aux tank also as there are lot of gum there as that
tank selcom gets used up.

On Sat, Jan 6, 2018 at 2:59 PM, Carl Stouffer wrote:

> I have been fighting fuel starvation issues for years, so I try to keep up
> with maintenance to help my fuel system be the best it can be. Today I
> replaced the two in line filters under the coach and the carb inlet filter
> on the Q-jet.
>
> After replacing the filters, I cut one of the in-line filters and the car
> inlet filter open to have a look at the elements. Both of the in-line
> filters appeared to be free flowing and no dirt came out of them when I
> blew them out into a rag. The carb filter had the slightest amount of very
> fine grit in the pleats, but it didn't seem excessively dirty.
>
> I don't remember when I last replaced these filters, but I'm sure the carb
> filter, at least was replaced less than 8000 miles ago.
>
> How often do you guys replace fuel filters and what do you use as a
> criteria for when to replace them. They are cheap, but not quick and easy
> to
> replace, making me reluctant to waste any more time on them than
> absolutely necessary.
> --
> Carl Stouffer
> '75 ex Palm Beach
> Tucson, AZ.
> Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive,
> Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American
> Eagles,
> Solar battery charging. GMCSJ and GMCMI member
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>



--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Fuel Filters [message #327923 is a reply to message #327920] Sat, 06 January 2018 18:27 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
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Registered: August 2004
Location: Spanish Fort, AL
Karma: 9
Senior Member
Replace them as part of your spring 'cleaning', getting the GMC ready for the season's travel. Easier at home, than along the side of the road.
Tom


2012 Phoenix Cruiser model 2552 KA4CSG
Re: [GMCnet] Fuel Filters [message #327942 is a reply to message #327923] Sun, 07 January 2018 00:30 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
Back in 1996 (I believe it was) we in the Chicago-Milwaukee EPA non-attainment area were forced to go to E-10 year round and it has been that way here ever since. MTBE was not approved or supplied here.

In 1995 and 1996 there was lots of doom and gloom articles with lots of added hype like Y2K about how we were all going to have fuel filter, fuel line, injector, fuel pump, and carb problems. There were opportunists trying to sell their preemptive fixes for big bucks. Not many people bought into it and did anything to prepare. They just used whatever came out of the pump and went on their way.

Since E-10 and 100% gas (E-0) came out of the same refinery and same terminals and were mixed at time of loading the delivery truck, the EPA placed their enforcement arm on the delivery truck drivers. It was a flat fine of $25,000 for any fuel truck driver caught dropping E-0 at a retail gas station in a non-attainment county. Off vehicle pumps road like farming, boats, and aviation, etc. were exempt.

Well nothing happened after in or after 1996 and in the 20+ years since then everybody has forgotten about the projected problem. I hate ethanol diluted gasoline as much as anyone for other reasons but the forecast disaster just never happened.

Around here where you think it might have been needed most, it is impossible to find any place stocking ethanol rated fuel line / hose. It can be special ordered for 3 times the normal line/hose prices.

I needed 3 feet of 1/2" fuel line a couple of months ago for a gas vent line on a GMC. I special ordered 3 feet from Oreily and the computer took the order. They had the standard 1/2" hose in stock, as did AutoZone, and Advance. In order to fill the 3 ft. order the warehouse sent a 100 foot roll and it took 3 days to get there from who knows where. They sold me 3 feet and put the rest in stock expecting to never be able to sell it. Their computer said that they had never sold that item before. They also did not stock ethanol rated hose in 1/4, 5/16, and 3/8 sizes.

The place ethanol did cause a problem was when pilots used it in airplanes, which is illegal. It softened up some of the sealants used in wet wing tanks causing them to seep. When the fuel in the tanks was replaced with non-ethanol diluted 100% gasoline the seeping stopped.

We all know that ethanol makes a good detergent. So if you are now using E-10 and your fuel system if full of junk (primarily varnish) from years of neglect, I suspect that over a period of time E-10 will dissolve that stuff and it will get carried away. If it is a rust issue you have it can also get carried away but not dissolve. If there are large particles greater than 10 or 20 micron they should be caught in the carb and inline filters. Hose problems, and fuel pump problems from E-10 I have never seen.

I have seen some very old hoses get very hard but they would have gotten that way over 40 years E-10 or not. I have one very hard one going to my Onan that someday I'll replace.

So based on over 20 years of local experience with mandated E-10, I do buy into to all of the E-10 hype.

There are still many other reasons not to like E-10 and I still use 100% gasoline whenever possible in my airplane, GMC, small engines, and cars.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Fuel Filters [message #327944 is a reply to message #327942] Sun, 07 January 2018 07:30 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
Senior Member

I redid my fuel system in 2010 with all ethanol resistant hose from Applied GMC. At that time, my tanks were spotless and have never had anything in them except E-10, with the exception of a few tanks of E-0 which it ran much better on.

I run through probably about 600 - 700 gallons of gas per year, so I doubt that there is any kind of build-up in my tanks. The only thing I found in the cut open filters was a very minor amount of grit, mostly in the carb filter.

I use Wix filters and understand that the 3/8" in line filters (33033) do not filter as fine particles as the carb filter (33048) so I understand some dirt getting past them. I'm guessing the fuel filters have little to do with the fuel starvation problems that I just can't seem to get a handle on.

Of all of the recommended remedies for this problem, the only ones I have not yet done are in tank fuel pumps, and fuel injection. The frustrating part is that the problem comes and goes and seems to have more to do with the gas - source, winter/summer mix, etc. than anything else.

We head up to Las Vegas on Friday for a trip to visit my daughter, son in law, and two grandchildren, so we'll see how it goes this time.



Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: Fuel Filters [message #328004 is a reply to message #327917] Mon, 08 January 2018 06:35 Go to previous messageGo to next message
Russell K. is currently offline  Russell K.   United States
Messages: 178
Registered: October 2016
Location: Dunedin, Florida
Karma: 4
Senior Member
Carl,
The Qjet fuel filter is inexpensive and easy to replace. I put a new one in at every oil change (<2000 miles). Like Tom P. said above, I'd rather do it in my driveway than on the side of the road. I'm a big fan of more maintenance, and less major repairs. As you know, grease, oil, and filters are cheap compared to major repairs.

http://www.gmcmhphotos.com/photos/data/7038/20170429_085158.jpg

Happy Travels,
Russell


1978 Eleganza II, Dunedin, Florida
Re: Fuel Filters [message #328010 is a reply to message #328004] Mon, 08 January 2018 08:42 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
Changed mine 10 or 12 years ago. I have one inline from each tank and one in carb. The socks are still on in the tanks (I think). If they ever get dirty I'll change them then. It is an easy job. I do carry spares somewhere in the coach. I have a Blazer with 240,000 miles on it. I have never changed that filter. Laurie's Jimmy had a gas gauge sending unit go out last year at around 150K miles. Heather changed that filter at the same time that she replaced the fuel pump sending unit for Laurie. You could still blow through the removed one.

I do not think that they need to be changed very often.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Fuel Filters [message #328015 is a reply to message #328010] Mon, 08 January 2018 08:53 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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Registered: March 2004
Location: Americus, GA
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Senior Member
Me neither, Ken. I don't think I've EVER changed one on Anything.

Ken Filter-Lucky H.

On Mon, Jan 8, 2018 at 9:42 AM, Ken Burton wrote:

> ​...
>
> I do not think that they need to be changed very often.
> --
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Fuel Filters [message #328034 is a reply to message #328015] Mon, 08 January 2018 13:37 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Registered: July 2006
Location: Belmont, CA
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Senior Member
One thing we are seeing;
One need to use the fuel from the Aux tank and use it down to at least 1/4
mark to keep the tanks half way clean.
Keep in mind that the filters will accumilate more particulets and gum from
the aux tank so prepare to change the fuel filters.

On Mon, Jan 8, 2018 at 6:53 AM, Ken Henderson
wrote:

> Me neither, Ken. I don't think I've EVER changed one on Anything.
>
> Ken Filter-Lucky H.
>
> On Mon, Jan 8, 2018 at 9:42 AM, Ken Burton wrote:
>
>> ​...
>>
>> I do not think that they need to be changed very often.
>> --
>>
> _______________________________________________
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>



--
Jim Kanomata
Applied/GMC, Newark,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
Re: [GMCnet] Fuel Filters [message #328036 is a reply to message #328034] Mon, 08 January 2018 14:05 Go to previous message
Matt Colie is currently offline  Matt Colie   United States
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Registered: March 2007
Location: S.E. Michigan
Karma: 7
Senior Member
From a lifelong history of managing fuel inventory, we use a standard method that has served us very well (now that everything works).
* Run on the main tank until it indicates half.
* Change to the Auxiliary (that will start at about half) and run it until the low fuel light comes on.
* Change back to the main and run it until the next planned fuel stop.

Part of this idea is to try to keep above the 1/4 on the main so there is fuel for the APU (genset) in case it is needed.
Another part of this thinking is that as the main fills first when fueling, we can count on getting new fuel in both tanks.

How many of you have been riding a motorcycle and reached down to change to the reserve only to find out that you left the fuel cock in the reserve position after you last filled the tank?? (I am not going to ask for a show of hands....)

Matt


Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
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