Go Back   Ford Truck Enthusiasts Forums > Older, Classic & Antique Trucks > 1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
Sign in using an external account
Register Forgot Password?


1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks Discuss the Early Eighties Bullnose Ford Truck

Welcome to Ford-Trucks Forums!
Welcome to Ford-Trucks.com.

You are currently viewing our forums as a guest, which gives you limited access to view most discussions and access our other features. By joining our community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join the Ford-Trucks Forums community today!





 
Reply
 
LinkBack Thread Tools Search this Thread
  #1 (permalink)  
Old 02-23-2012, 11:25 AM
Floggit Floggit is offline
New User
 
Join Date: Feb 2012
Location: Southern Oregon
Posts: 10
Floggit is starting off with a positive reputation.
Unhappy Stuttering motor

I'm new here, so please go easy on me. I have an '81 F150 with a 300" six and a four speed stick. It's bone stock and has ~168 thou. on it. The truck has always been reliable transportation and I've only put about 4 or 5 thousand miles on it a year. I've been real good on the maintenance and don't use the truck for much other than transportation on the freeway to a near by city.

Lately though, the truck has been suffering from poor mileage (10-12 mpg mixed, but Oregon puts booze in their gas) and even more recently, has been having performance issues. It will stutter slightly when starting out from a red light. If I get the truck on the freeway, it has a real hard time getting up to 65 mph and once there, seems to have no power. Strangely enough though, the truck still runs good enough (despite the stuttering when starting out) to get around in town at slower speeds.
  • I put in a new fuel pump, but that wasn't the problem.
  • I pulled the carb (YFA non-feedback, E1TE-DA) and promptly lost the pump check weight, so I carefully fabricated a new one (they're supposed to be .304" long and .140" wide, square in cross-section but I made mine round.) Then I *very* carefully rebuilt the carb. The symptoms remained unchanged. I've gotten so good at taking off that carb, I can do it in about five minutes now.
  • I've set the idle mixture screw, float and metering rod *very* carefully to the correct specs.
  • I've verified that the distributor advance mechanism is still working correctly and have checked the timing, which is dead on.
  • I've checked my plug wires and plugs. They're all good.
  • I've checked my air filter and although it's used, it only has a couple of thousand miles on it and is still serviceable (I can see through it when held up to the light.)
  • My fuel filter is like new and is clear.
  • I have no fuel line leaks.
  • My gas tanks (there are two) have no gunk in them. I blew compressed air through the fuel lines after disconnecting the line from the fuel pump (with gas caps *off* to avoid pressurizing the tanks and blowing up the truck!)
  • There are no leaks in any of the vacuum lines and they are all correctly attached.
  • The EGR valve is new and has no problems.
  • My belts are all good and my thermactor air pump is working correctly.
  • My exhaust system is in good shape and my heat riser isn't stuck, is opening correctly.
I tried to make the above list as complete as I can, but I'm an old dude and may have forgotten something I tried, so please cut me some slack. I'll definitely let you know if I tried something which you suggest.

I am at my wit's end with this problem. Add to this that I get to work on the thing in the street in front of my house because I don't have a driveway or garage, that the truck is parked facing uphill so that everything I drop rolls away to someplace downtown, and you can see that it's not a lot of fun to deal with.

Does anybody have any other ideas what it might be? Thanks in advance for any help and suggestions!

Regards,
Floggit
Reply With Quote
  #2 (permalink)  
Old 02-23-2012, 02:42 PM
1986F150six 1986F150six is offline
Posting Guru
 
Join Date: Jul 2009
Location: Sheffield, AL
Posts: 2,425
1986F150six has a great reputation on FTE.1986F150six has a great reputation on FTE.1986F150six has a great reputation on FTE.1986F150six has a great reputation on FTE.1986F150six has a great reputation on FTE.
Welcome to the forum, Floggit!

A very thorough list... you did not mention the distributor cap or rotor. Have you checked them? What about the catalytic converter? A compression test will tell you if the engine has a weak cylinder or more. What about the choke? Is it opening properly?
Reply With Quote
  #3 (permalink)  
Old 02-23-2012, 02:54 PM
Franklin2's Avatar
Franklin2 Franklin2 is offline
Moderator
 
Join Date: Jan 2001
Location: Staunton VA
Posts: 32,463
Franklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant future
When it's sitting in the driveway, fully warmed up and idling, does it hesitate when you smash the gas to the floor for a second?
__________________
Dave F

1989 F250 XLT Diesel
Reply With Quote
  #4 (permalink)  
Old 02-23-2012, 04:32 PM
Floggit Floggit is offline
New User
 
Join Date: Feb 2012
Location: Southern Oregon
Posts: 10
Floggit is starting off with a positive reputation.
Quote:
Originally Posted by 1986F150six View Post
Welcome to the forum, Floggit!

A very thorough list... you did not mention the distributor cap or rotor. Have you checked them? What about the catalytic converter? A compression test will tell you if the engine has a weak cylinder or more. What about the choke? Is it opening properly?
Thanks for replying!

Sorry, I knew I forgot something. The distributor cap and rotor are fine. The catalytic converter is... well, it's there. I don't know how to check it. If it's messed up, I can't afford a new one and would probably just remove it.

The choke has always been disabled. The original owner turned it all the way over to lean and I like it that way anyway (I've owned this truck since around 1995 or so.) I verified that the choke valve is all the way open too.

Regards,
Floggit
Reply With Quote
  #5 (permalink)  
Old 02-23-2012, 04:35 PM
Floggit Floggit is offline
New User
 
Join Date: Feb 2012
Location: Southern Oregon
Posts: 10
Floggit is starting off with a positive reputation.
Quote:
Originally Posted by Franklin2 View Post
When it's sitting in the driveway, fully warmed up and idling, does it hesitate when you smash the gas to the floor for a second?
Thanks for replying!

I don't have a driveway, unfortunately. Remember, I have to work on this thing where it's parked in front of my house. But yes, when it's fully warmed up and idling (which it does nicely), there is a very slight hesitation when I mash the pedal to the floor for a second. And by the way, it starts right up when it's cold too.

Regards,
Floggit
Reply With Quote
  #6 (permalink)  
Old 02-23-2012, 06:44 PM
Franklin2's Avatar
Franklin2 Franklin2 is offline
Moderator
 
Join Date: Jan 2001
Location: Staunton VA
Posts: 32,463
Franklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant futureFranklin2 has a brilliant future
Take the aircleaner off, and get a flashlight. Climb up in the engine compartment, and shine the flashlight down the throat of the carb(engine is off). While looking down the carb throat, push the throttle back. The very slightest movement should start the accel pump squirting fuel. If you have any delay in the fuel stream, or your fuel stream is not very strong, you still have problems with your carb. Your accel pump needs to inject a good bit of fuel AS SOON as the throttle is opened, to cover up and prevent the engine from going lean.
__________________
Dave F

1989 F250 XLT Diesel
Reply With Quote
  #7 (permalink)  
Old 02-23-2012, 08:09 PM
82f100460's Avatar
82f100460 82f100460 is offline
Posting Guru
 
Join Date: Jan 2012
Location: Dallas, GA
Posts: 1,410
82f100460 is gaining momentum as a positive member of FTE.82f100460 is gaining momentum as a positive member of FTE.
I was also going to recommend the catalytic converter. My neighbor just a couple of weeks ago had very similar symptoms. After driiving it...the exhaust manifold and converter were glowing red it was so hot. His was completely plugged....possibly your's is starting to plug?
Reply With Quote
  #8 (permalink)  
Old 02-24-2012, 02:48 PM
jonny.redneck jonny.redneck is offline
Freshman User
 
Join Date: Feb 2012
Posts: 26
jonny.redneck is starting off with a positive reputation.
I had this problem also with my 84 302 where id replace the fuel filter and 5 miles later it would plug up again. After about 5 times replacing it and cleaning everything it solved the problem. Its a cheap and simple fix and might be worth a try.
Reply With Quote
  #9 (permalink)  
Old 02-29-2012, 03:42 PM
Floggit Floggit is offline
New User
 
Join Date: Feb 2012
Location: Southern Oregon
Posts: 10
Floggit is starting off with a positive reputation.
Well, I found out what the problem(s) were. Turns out I had a broken spark plug from overtorqueing it. Also, had a bad distributor stator. One problem is usually easy to find, but two at the same time makes it far more difficult. Regardless, the truck is running fine now. Hope it stays fixed for a while this time. Thanks to everybody who replied!

Regards,
Floggit
Reply With Quote
Old 02-29-2012, 03:42 PM
Reply

Go Back   Ford Truck Enthusiasts Forums > Older, Classic & Antique Trucks > 1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks

Tags
300, carb, davidson, f150, ford, harley, stutter, supercharger

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On
Forum Jump



All times are GMT -5. The time now is 06:27 PM.


Powered by vBulletin® Version 3.7.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Advertising - Terms of Use - Privacy Statement - Jobs
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. FordŽ is a registered trademark of the Ford Motor Company.

vbulletin Admin Backup