Fuel Filter Replacement

1985air345 · 02-17-2003, 06:57 AM

I know we probably all have different in-line filters so I won't ask what model.

What is your fuel filter replacement routine? Are these filters rated for gallons processed? What is the normal life expectancy? We do use lots of gas in these hogs!

My 345 started to have fuel delivery problems this weekend. The extra pump still had the 12.7 volts so I expect it's the filter. It has been about 15 months since it was replaced. My fuel problems were intermitent as I could drive for an hour at 3,200 rpms and then have trouble getting over a hill.

I did try a filter at Wal-mart but the in-take and out-take tubes were just slightly smaller than the existing filter.

PeterH-79MH · 02-17-2003, 07:21 AM

Fred,
get out the wrenches. Check and replace this filter first. There is a good chance it never has been replaced since 1985. It is located inside your fuel line at the carburetor.

cooperhawk · 02-17-2003, 08:49 AM

There are three fuel filters. One at the carburetor as shown in a previous picture and one by the step against the frame and one at the electric pump. I have found that when the electric pump goes bad it will run but will not pump fuel. You have to disconnect the fuel line on the "out" side of the electric pump and then run a line into a container and turn on the pump (you can do that from underneath by pulling the positive wire on the pump and reconnecting it) to assure that it is actually delivering gas, if it doesn't the mechanical pump will pump enough to drive the unit on flats and some minor hills but the engine will starve for gas on long or steep hills. I have had this experience.
The Inline filters at the step and at the electric pump are GM#854619 or NAPA #3033 or equivalents from other manufacturer's.

1985air345 · 02-17-2003, 10:07 AM

I know the filter at the carb was changed twice in the last 15 months. I did it once myself. The electric and mechanical pumps are also fairly new (15 months).

I'll start with the in-line one since that would catch 95% of the crud. This whole thing started on this trip. I took it out a few weeks ago and drove it pretty hard (harder than Peter would be pleased with) and had no problems. Maybe I just got a really bad tank of gas. More to come.

wb13798 · 02-17-2003, 12:53 PM

i had filter problems and bad gas at the same time . i changed all of the filters and still had a problem. i was at walmart and decided i best put some gas treatment in the tank that cleared the problem some what. when i put new gas in the tank the engine ran ok . this dont make sense i had to replace the filter on the carberator about 200 miles later. havent had any problems since. i dont but gas at that fuel stop any more. lol
al

just a pain getting under the beast, but it can be done..

1985air345 · 03-05-2003, 05:15 PM

I did remove the current fuel filter. It's a Wix 33299 model. I got the Carquest branded version. Since they only stock one at a time, I'll need to order it to have a spare handy.

I also replaced four 4" sections of 5/32 vacuum hose and the PCV valve. The PCV valve was easy. The old one did not rattle like the new one! I did notice that one of the hoses was disconnected. I still have some deteriorated hoses but they are connected to fittings. There are two that have two hoses coming out of them. I am assuming the piece comes with the two hoses pre-attached. I'll need a manual on the 454 engine to identify them for the parts place.

The combination of the above repairs did solve my hill climbing problem. I took 'Jellybean III' out for some good old fashioned hard driving just to test her. She did good. The shifting seemed a little different but that might be me. I never lost power even after intentionally slowing down at the bottom of some hills!

Now it's back to being nice to make Peter happy (and to make it last longer!).

74Argosy24MH · 03-05-2003, 07:22 PM

On the back of the manifold is a hex shaped fitting with 3 vacuum lines. If you changed one that goes to a metal tube down the back of the motor it is for the vacuum modulator on the trans, this controls shifting. There is another short rubber tube at the trans end.

John

1985air345 · 03-05-2003, 08:07 PM

John,

So it wasn't my imagination! One of the deteriorated lines goes to that tube at the back. I pulled it off but traced it to the hex shaped fitting that the hoses are a part of. I did blow out the junk in the metal tube and re-attached the old hose. Somehow I'll find out how to order those fittings/hoses and get them replaced.

74Argosy24MH · 03-06-2003, 07:05 AM

Not sure exactly what fittings you mean, but if it is the plastic T's they should be reusable. Slit the end of the hose and it will come off without breaking the plastic. If the are or do break you can get them at the "Help" sections of the chain parts stores. They should also have all different sizes of tubing.

John