Home page
SPONSOR AD

Support our Vendors!  |  Advertise Here

Topic: Sediment clogging fuel filter in '74 LS4

in Forum: C3 Fuel, Emission Control, and Exhaust Systems


Already a Member?
Login
Not yet a Member?
Register for Free!

Sediment clogging fuel filter in '74 LS4 (1/6)
 12/24/13 9:36am
Hawkshaw44
Former Member

Send Private Message

foster, RI - USA

Vette(s):
1982 crossfire coupe, white, fuel injected 1974 LS4 454cc, Convertible, 3 Speed Automatic w/AC, Medium Red, Silver Interior, White Top, Black Hardtop, matching numbers.


Joined: 12/15/2013
Posts: 11

I am on my 4th fuel filter and at this rate it is not my last. This is a 1974 convertible with the 454 big block. The '74 had been sitting a few years until my neighbor finally agreed to sell it to me. She took great care with this Vette leaving very little for me to do. This is one project. If I run it without the fuel filter, which I had to do to get it home, there is no problem. Runs wonderful. Like I said, my neighbor, only one mile away. I had to chance it and the carburetor seems fine. I immediately installed a fresh filter. The sediment trapped by the fuel filter is fairly decent sized. Say slightly larger than sugar grains but not consistently the same size.
 
I siphoned the old gas out of the tank prior to putting in fresh gas and driving it up the street. What are my options guys? I used a shop-vac on my 1982 rigged with a flexible garden hose to clean out some sand a few years back. But that was an electric pump that came out with the sending unit leaving a good sized hole to navigate the vacuum.
 
I could really use some help on this one.


______________
Our Sponsors help support C3VR
Re: Sediment clogging fuel filter in '74 LS4 (2/6)
 12/24/13 10:23am
knotacare
Former Member

Send Private Message

Newark, DE - USA

Vette(s):
1968 Conv, 454HO,500HP-600TQ, TKO-600,3:70 HD rear,hotrod air, custom paint & suspension,1973 Ruby Red,T-top, 383 Stroker, TK)-500,frame off restro, 1967 Dodge Coronet, 340 stroker to 406, Dana 60


Joined: 7/26/2004
Posts: 463


I've seen this done on older cars with rust scale in the tank. The tank has to come out,  put a small amount of pebbles in the tank & add some kerosene. Then shake the tank at all angles. Use a light & small mirror to check the inside of the tank. Rinse with kerosene, then a small amount of gas, let dry & recheck for scale. If that doesn't work you'll have to buy a new tank. Your gas lines could also be bad. This is done on cars that usually have no replacement tanks available, but should work on vettes. I personally would just replace the tank & if it continues you have bad lines.
Alan


______________

                                               

Re: Sediment clogging fuel filter in '74 LS4 (3/6)
 12/24/13 10:58am
Hawkshaw44
Former Member

Send Private Message

foster, RI - USA

Vette(s):
1982 crossfire coupe, white, fuel injected 1974 LS4 454cc, Convertible, 3 Speed Automatic w/AC, Medium Red, Silver Interior, White Top, Black Hardtop, matching numbers.


Joined: 12/15/2013
Posts: 11

Thanks. That sounds like a good idea. I will try to save the existing tank. A little 3/8" washed pea stone is piled on the side of my house.
 
Merry Christmas


______________
Re: Sediment clogging fuel filter in '74 LS4 (4/6)
 12/24/13 1:37pm
eldredjamesLifetime Member
Lifetime Member
Send Private Message

Temple City, CA - USA

Vette(s):
1969 Daytona Yellow. 350 / Automatic.


Joined: 10/3/2010
Posts: 365

Hawkshaw44 said: The sediment trapped by the fuel filter is fairly decent sized. Say slightly larger than sugar grains but not consistently the same size.

I had the same problem with my '69.  We thought someone had put sugar in the gas tank.  Took it to have it fixed.  Turned out the water from the old gas had rusted out the inside of the tank including the fuel guage sender.  And the gas tank had started to leak, too.  Bottom line: new tank, sender, rebuild carb, new hose from pump to carb, 3rd new filter, and clean out gas pump.  Further, the gas lines were blown out.

Now I add stabilizer at every fill-up.  Only add 10 gallons so the stabilizer is easy to measure, and the gas cycles quicker.

Jim


Re: Sediment clogging fuel filter in '74 LS4 (5/6)
 12/26/13 2:40pm
dyoes
Former Member

Send Private Message

Zachary, LA - USA

Vette(s):
1974 L-48 Auto. Just your basic Vette. GM crate motor w/vortec heads and intake. Crane cam. Scorpion rockers, Edelbrock carb. Lots of parts still in boxes... :(


Joined: 1/27/2013
Posts: 201

I replaced the tank in my '74 with one from a '75.  The '75 and up tanks have a rubber bladder.  Before installing the tank, I opened up and wiped down the bladder to get it perfectly clean.  The sending unit is on the top of the '75 tank, vice the bottom of '74 and earlier, so I had to reroute the fuel hose and sender pickup wire.  But I'll never have to worry about corrosion from the tank again!

______________


"Let them that don't want none have memories of not gettin' any."
- Brother Dave Gardner

Re: Sediment clogging fuel filter in '74 LS4 (6/6)
 12/26/13 3:37pm
rraider1
Former Member

Send Private Message

Woodland, WA - USA

Vette(s):
1977 T-Top,350,Auto Black Ruby Pearl,Steeroids R&P conversion


Joined: 10/14/2003
Posts: 1165

75 to 77 have the rubber bladder that should have an extra hose on top of tank to help equalize pressure to keep the bladder from collapsing causing fuel tank capacity issues. their is a picture in a topic under Gas tank fuel QTY. hopefully someone will have more info I will look through my stuff if I have more info. It is supposed to be covered in the 76 supplement to the GM service manual. It is a .035" vent tube and I believe it ran to the Vapor  canister 

|UPDATED|12/26/2013 12:37:18 PM (AZT)|/UPDATED|
Our Sponsors help support C3VR