FE Sputtering
New User
Joined: Jul 2001
Posts: 8
Likes: 0
FE Sputtering
Just looked thru the past threads on the timing/tuning of the FE motors, especially the 390/360 trucks. The problems that I've had are with the hesitation and sputtering with these motors. I recently purchased a 71 F-250 with a 390 2V (donated from a grocery-getter) NP235, Dana 24, and 4.10's. Hesitation was solved with a new carb being installed, but the sputtering/bucking under upper acceleration or load was unbearable. I immediately advanced the timing(by ear) and took it for a drive. It liked the timing but didn't solve the sputtering. I advanced the timing until it wants to ping, and left it. When I put the overhead camper on, it was fine until on a hill it started sputtering. I mashed it to WOT and it temporarily stopped. Same thing on the way back from camping. It has a new distributor, but I thru the points & condenser into the trash and updated with a Pertronix and coil (new Autolite 45 gapped at 0.50, but the transfer case is out so no test drives yet. My vacuum is right of the carb. I'll try plugging the vacuum line off if the pertronix didn't help.
It seems almost every FE 390/360 truck has done this. My experience with small-blocks have never done this. Am I alone?
It seems almost every FE 390/360 truck has done this. My experience with small-blocks have never done this. Am I alone?
Senior User
Joined: Apr 2001
Posts: 128
Likes: 0
FE Sputtering
I'd look at things like fuel filters and accelerator pumps to cure the sputtering under acceleration. In order to accelerate, engines need a richer fuel/air ratio, and if they don't get it, it leads to the sputtering you describe, bogging, and slow acceleration. Might be worthwhile to clean out your carburator's jets, too.
Another thing you might look at is the condition of your ignition components: inspect/clean the spark plugs, replace the spark plug wires with quality items if needed, and get a good cap and rotor set with brass contacts. One needs to be vigilant with the ignition and fuel systems on these older engines.
One problem I did have with my current FE motor was dying when I slowed quickly to a stop or went downhill for a long time with my foot off the gas. I finally checked the fuel pressure and found that the fuel pump relief valve was stuck shut and that fuel pressure was great engouh to overwhelm the float bowl valve and flood the carburetor when there was reduced demand for gas.
Another thing you might look at is the condition of your ignition components: inspect/clean the spark plugs, replace the spark plug wires with quality items if needed, and get a good cap and rotor set with brass contacts. One needs to be vigilant with the ignition and fuel systems on these older engines.
One problem I did have with my current FE motor was dying when I slowed quickly to a stop or went downhill for a long time with my foot off the gas. I finally checked the fuel pressure and found that the fuel pump relief valve was stuck shut and that fuel pressure was great engouh to overwhelm the float bowl valve and flood the carburetor when there was reduced demand for gas.
Thread
Thread Starter
Forum
Replies
Last Post
ford390gashog
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
105
Dec 4, 2015 02:01 PM
FE427TP
1973 - 1979 F-100 & Larger F-Series Trucks
7
Jun 14, 2001 12:43 PM
