Fuel filter too small?
Thread Starter
|
Elder User
Joined: Aug 2007
Posts: 503
Likes: 0
From: arizona
Fuel filter too small?
it's been two weeks since I got my tranny rebuilt and today I got on it somewhat. Anyways, the truck was sort of sputtering like it wasn't getting enough fuel( Don't recall it doing this before the rebuild). My filter is newer but it is one of those that is close to the carb and the filter is only like two inches. Would a larger filter help me or is this possibly something else. ( also, the carb, fuel pump were replaced two months ago).
TIA,
Mike
TIA,
Mike
Last edited by azfordf100man; Nov 19, 2007 at 02:59 PM.
Fleet Mechanic
Joined: Aug 2007
Posts: 1,836
Likes: 261
From: Piney Woods of East Texas
I have several filters on mine. One large one at the tank, 1 at the carb. If it did not do this before, check to see if the modulator hose is connected and not colasped. I had the rubber hose on mine get soft and colasped, and created a hole in the hose.
Thread Starter
|
Elder User
Joined: Aug 2007
Posts: 503
Likes: 0
From: arizona
Originally Posted by merlynr
Make sure you don't have another filter upstream somewhere. Fuel pump,frame rail,look around.
Mike
Ford Parts Specialist
Joined: Nov 2006
Posts: 88,826
Likes: 787
From: Simi Valley, CA
From the early 1960's thru 1972, Ford V8 trucks have a cartridge fuel filter inside the fuel pump. Look at your pump...is there a tomato juice sized can on it? If so...there a fuel filter inside. It rarely gets changed, because ppl don't know it's there. The can screws on/off.
C4AZ-9365-A .. Fuel Filter (Motorcraft FG-1)
C4AZ-9365-A .. Fuel Filter (Motorcraft FG-1)
!["Beemer Nut"'s Avatar](data:image/svg+xml;utf8,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 50 50'><circle class='avatar-circle-default' fill='%23bc5285' cx='25px' cy='25px' r='20px'></circle><text class='avatar-text-default' x='49%' y='53%' fill='white' text-anchor='middle' alignment-baseline='middle'>"</text></svg>)
Post Fiend
Joined: Dec 2003
Posts: 6,658
Likes: 4
From: "Islander"
"Tee" off at the carb with a pressure gauge in the cab and run it hard thru the upper rpm range under full throttle conditions like up a grade checking pressure as your motor may be demanding more fuel than the fuel pump is providing.
This is where a wide band fuel/air gauge in the system helps vs spending money on unneeded replacement parts only guessing. Jetting correct overall?
Add to this a tach and vacuum gauge as standard items on a gear headed daily driven truck.
I'm guessing this is a slush box, was it built to your motors output as well your intended use or the truck like stall and shift points?
Tranny and engine should work together helping each other as a miss match will not only cause frustration but a uneccesary hatred of your truck.
This is where a wide band fuel/air gauge in the system helps vs spending money on unneeded replacement parts only guessing. Jetting correct overall?
Add to this a tach and vacuum gauge as standard items on a gear headed daily driven truck.
I'm guessing this is a slush box, was it built to your motors output as well your intended use or the truck like stall and shift points?
Tranny and engine should work together helping each other as a miss match will not only cause frustration but a uneccesary hatred of your truck.
Last edited by "Beemer Nut"; Nov 19, 2007 at 10:04 PM.
Trending Topics
Fleet Mechanic
Joined: Dec 2006
Posts: 1,338
Likes: 6
From: UPSTATE NY
Originally Posted by blue68f100
I have several filters on mine. One large one at the tank, 1 at the carb
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Lead Driver
Joined: Jan 2003
Posts: 9,893
Likes: 12
From: Ohio
Filters don't regulate pressure. I assume the big one at the tank was catching the major particles(Like rust from tank) from reaching the pump, and the small one keeps the needle/seat clean in carb.
How's the dizzy? Check the timing lately?
How's the dizzy? Check the timing lately?
Fleet Mechanic
Joined: Dec 2006
Posts: 1,338
Likes: 6
From: UPSTATE NY
ahh what a great idea! i am running a small performance one right before the carburetor, and i removed the one inside the fuel pump. i am going to have to put that sucker back in there. dirt in my fuel pump does not sound like a good thing
Lead Driver
Joined: Jan 2003
Posts: 9,893
Likes: 12
From: Ohio
There are rubber diaphrams in the pump(one way valves) and if something gets caught in them they will not pump(no suction/pressure). Not sure how many are in a stock pump, but a Holley mech. pump has three. BUT, if one gets stuck, it will definitely drop in pressure as it allows fuel to back feed.
If you don't want one in the pump, just put a small plastic one inline back at the frame where the tank line comes thru floor of cab. OR put it before pump where line comes from frame. It's not mandatory, but in the name of "keep it clean" it surely doesn't hurt.
If you don't want one in the pump, just put a small plastic one inline back at the frame where the tank line comes thru floor of cab. OR put it before pump where line comes from frame. It's not mandatory, but in the name of "keep it clean" it surely doesn't hurt.
Post Fiend
Joined: Dec 2003
Posts: 6,658
Likes: 4
From: "Islander"
The Carter mechanical pump with screws holding it together have two valves.
They look like 3/4" diameter freeze plugs with holes with a thumb tack shaped viton valve. One up the other down for a suction / pressure check valving.
The valve is inserted into a stepped bore with three sake marks to hold the valve in place in the pump casting.
I had a pump that would lean me out at random on the highway but would correct itself within seconds. This I saw on the F/A ratio gauge when it happened.
On a road trip it finally stopped the truck dead. Took the pump apart on the side of the highway and found that the pressure valve was out of its pocket it was never staked when assembled. Used a 3/8" tap as a center punch and staked the valve, assembled and on the road again in less than an hour. Good thing it was a screw together pump vs these newer crimped together pumps. I reported about this right after the 4th of July back in 2005. Strange things can and will happen.
They look like 3/4" diameter freeze plugs with holes with a thumb tack shaped viton valve. One up the other down for a suction / pressure check valving.
The valve is inserted into a stepped bore with three sake marks to hold the valve in place in the pump casting.
I had a pump that would lean me out at random on the highway but would correct itself within seconds. This I saw on the F/A ratio gauge when it happened.
On a road trip it finally stopped the truck dead. Took the pump apart on the side of the highway and found that the pressure valve was out of its pocket it was never staked when assembled. Used a 3/8" tap as a center punch and staked the valve, assembled and on the road again in less than an hour. Good thing it was a screw together pump vs these newer crimped together pumps. I reported about this right after the 4th of July back in 2005. Strange things can and will happen.
Thread
Thread Starter
Forum
Replies
Last Post
Mitchel Wincentaylo
1967 - 1972 F-100 & Larger F-Series Trucks
9
Mar 16, 2017 02:17 PM
anthonym92
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
6
Aug 17, 2015 08:32 AM
79outlawf150
1973 - 1979 F-100 & Larger F-Series Trucks
1
Jun 1, 2010 07:42 PM
