Notices
1973 - 1979 F-100 & Larger F-Series Trucks Discuss the Dentsides Ford Truck
Sponsored by:
Sponsored by: Moser

Flames and Backfire

Thread Tools
 
Search this Thread
 
Old Mar 1, 2005 | 02:33 PM
  #1  
Repsher's Avatar
Repsher
Thread Starter
|
Freshman User
Joined: Dec 2003
Posts: 30
Likes: 0
Flames and Backfire

I have a 79 F-350, with the 400 engine in it, 4 on the floor with straight pipes. when I go through the gears each time I put the clutch in there is a loud bang out the pipes, or several depending on RPMs and at night you can see flames shoot out the exaust pipes (around 2 feet at high revs).

My questions is:
What is going on here?

I rather enjoy driver her and being loud but I wanna make sure there just isn't an internal problem and I'm not ripping my engine up. Thanks
Mike
 
Reply
Old Mar 1, 2005 | 03:11 PM
  #2  
SwOkcOffRoader's Avatar
SwOkcOffRoader
Postmaster
20 Year Member
Joined: Jul 2003
Posts: 2,544
Likes: 2
From: okc
does it have a catalytic convertor on it?? ive seen them get so clogged that they glow bright red and spit out flames when you let off the throttle, lets just say the rings didnt last very long in my pontiac, i was in high school and thought it looked cool...didnt know what kind of damage i was causing doing it though.........
 
Reply
Old Mar 1, 2005 | 03:15 PM
  #3  
michaelbrainardatwor's Avatar
michaelbrainardatwor
More Turbo
Joined: Mar 2004
Posts: 534
Likes: 1
From: manson
Don't let the cops catch ya! My old 66 chevy pu would throw hellish flames...rev it up a bit...chop the ignition...turn it back on..BANG...I got stopped one night, someone had called in gun shots. OOPS. HIDE THE BEER!
 
Reply
Old Mar 1, 2005 | 03:31 PM
  #4  
460me's Avatar
460me
More Turbo
20 Year Member
Photogenic
Liked
Loved
Joined: Nov 2003
Posts: 747
Likes: 26
I had my dissy all jacked upped and trying to start it,it sounded like a cannon went off.Yeah about a minuite later the cops show up. 79- 460
 
Reply
Old Mar 1, 2005 | 03:36 PM
  #5  
mark a.'s Avatar
mark a.
Lead Driver
20 Year Member
Photogenic
Joined: Mar 2004
Posts: 8,922
Likes: 152
Maby your timing chain is going bad ?
 
Reply
Old Mar 1, 2005 | 05:44 PM
  #6  
pantherscat's Avatar
pantherscat
Junior User
Joined: Feb 2005
Posts: 99
Likes: 0
you may have a burnt valve allowing excess fuel into the exhaust and causing a fire in the exhaust system.
 
Reply
Old Mar 1, 2005 | 05:47 PM
  #7  
highboy 74's Avatar
highboy 74
Senior User
Joined: Nov 2003
Posts: 495
Likes: 0
From: WA
You might have the timing a bit too far advanced.
 
Reply
Old Mar 1, 2005 | 09:36 PM
  #8  
IUPBone's Avatar
IUPBone
New User
Joined: Oct 2004
Posts: 10
Likes: 0
I would say your idle mixture might be a bit lean, try turning it out a turn or so, that might help. This is one of the disadvantages with running straight pipes, you hear everything that goes on.
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

Ford's 2001 Explorer Sportsman Concept Looks For a New Home

 Verdad Gallardo
story-1

10 Best Ford Truck Engines We Miss the Most!

 Joe Kucinski
story-2

2026 Shelby F-150 Off-Road: Better Than a Raptor R?

 Brett Foote
story-3

2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

 Michael S. Palmer
story-4

10 Most Surprising 2026 Ford Truck Features!

 Joe Kucinski
story-5

Top 10 Ford Trucks Coming to Mecum Indy 2026

 Brett Foote
story-6

5 Best / 5 Worst Ford Truck Wheels of All Time

 Joe Kucinski
story-7

Ford Super Duty: 5 Things Owners LOVE, 5 Things They LOATHE!

 Joe Kucinski
story-8

Every 2026 Ford Truck Engine RANKED from WORST to FIRST!

 Michael S. Palmer
story-9

The Best F-150 Deal of Every Trim Level (XL through Raptor)

 Joe Kucinski
Old Mar 2, 2005 | 06:43 PM
  #9  
Repsher's Avatar
Repsher
Thread Starter
|
Freshman User
Joined: Dec 2003
Posts: 30
Likes: 0
Running lean you think not rich? Is that because of the backfire? With the flames I was thinking it might be too rich and not fully igniting the fuel in the cylinder?
 
Reply
Old Mar 2, 2005 | 07:48 PM
  #10  
IUPBone's Avatar
IUPBone
New User
Joined: Oct 2004
Posts: 10
Likes: 0
nope

Unless you were running really darn rich, maybe. I think its running learn. Try turning the screw out and try it, what do you have to lose???
 
Reply
Old Mar 2, 2005 | 08:20 PM
  #11  
ClonedLightning's Avatar
ClonedLightning
New User
Joined: Feb 2005
Posts: 8
Likes: 0
I'd have too agree with checking your fuel mixture....If that isn't were the problem lies a timing issue might be the culprit...a comp test to check your valve-train might also be a good idea. I had an 85' Ramcharger with a simular issue and it came down to the timing being set about 14 deg BTD at idle (way off rec specs)
 
Reply
Old Mar 2, 2005 | 08:33 PM
  #12  
ford390gashog's Avatar
ford390gashog
Fleet Owner
20 Year Member
Liked
Loved
Community Favorite
Joined: Jan 2004
Posts: 26,007
Likes: 575
From: Brentwood,CA
Club FTE Gold Member
sounds like you mixture is way to lean and the timing is off
 
Reply
Old Mar 2, 2005 | 10:02 PM
  #13  
Mil1ion's Avatar
Mil1ion
New User
Joined: Jan 2008
Posts: 0
Likes: 24
Those adjustment screws on the carb are ONLY for the Idle circuit..... not any other circuit.
How about a Float level too high ?

Timing Chain & gears ?

or just Timing
 
Reply
Old Mar 3, 2005 | 12:22 AM
  #14  
IUPBone's Avatar
IUPBone
New User
Joined: Oct 2004
Posts: 10
Likes: 0
Yes, I meant to say the idle mix is too lean. That is causing his problems. There is no screw for the main mixture, only different jet sizes, which would have no effect on what is going on with his truck. He needs a richer idle mix to help solve the trouble.


EDIT:

Also, the problem he is saying is he is having "after burning" in the exhaust. Like when going down hill and leaving off the gas, you hear a lot of pops. Like on the newer "ricers" with the loud mufflers, whenever they shift or go down hill and slow down, the injectors shut down and you have the popping due to the learning mixture.
 
Reply
Old Mar 3, 2005 | 02:20 PM
  #15  
Mil1ion's Avatar
Mil1ion
New User
Joined: Jan 2008
Posts: 0
Likes: 24
Attention ALL User's .


EVERYBOY has 60 minutes to edit their own posts.

Editing 5 kb of info in a post ,rather than 2 minutes later making the data base remember ALL of your profile with another post uses less space & helps FTE with bandwith waste.
 
Reply



All times are GMT -5. The time now is 05:25 AM.

story-0
Ford's 2001 Explorer Sportsman Concept Looks For a New Home

Slideshow: Ford's bizarre fishing-themed Explorer concept has resurfaced after spending decades largely forgotten.

By Verdad Gallardo | 2026-05-12 18:07:46


VIEW MORE
story-1
10 Best Ford Truck Engines We Miss the Most!

Slideshow: The 10 best Ford truck engines we miss the most.

By Joe Kucinski | 2026-05-12 13:09:47


VIEW MORE
story-2
2026 Shelby F-150 Off-Road: Better Than a Raptor R?

Slideshow: first look at the 810 hp 2026 Shelby F-150 Off-Road!

By Brett Foote | 2026-05-12 12:50:07


VIEW MORE
story-3
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

Slideshow: Everything You Need to Know about the 2027 Super Duty Carhartt Package!

By Michael S. Palmer | 2026-05-07 17:51:06


VIEW MORE
story-4
10 Most Surprising 2026 Ford Truck Features!

Slideshow: 10 most surprising Ford truck options/features in 2026.

By Joe Kucinski | 2026-05-05 11:17:22


VIEW MORE
story-5
Top 10 Ford Trucks Coming to Mecum Indy 2026

Slideshow: Here are the top 10 Fords coming to Mecum Indy 2026.

By Brett Foote | 2026-05-04 13:49:49


VIEW MORE
story-6
5 Best / 5 Worst Ford Truck Wheels of All Time

Slideshow: The 5 best and 5 worst Ford truck wheels of all time

By Joe Kucinski | 2026-04-29 16:49:01


VIEW MORE
story-7
Ford Super Duty: 5 Things Owners LOVE, 5 Things They LOATHE!

Slideshow: Ranking the 5 things owners love about their Super Duty and 5 things they don't

By Joe Kucinski | 2026-04-29 16:36:49


VIEW MORE
story-8
Every 2026 Ford Truck Engine RANKED from WORST to FIRST!

Slideshow: Ranking all 12 Ford truck engines available in 2026.

By Michael S. Palmer | 2026-04-22 13:32:20


VIEW MORE
story-9
The Best F-150 Deal of Every Trim Level (XL through Raptor)

Slideshow: The best Ford F-150 deal for every trim level (XL through Raptor)

By Joe Kucinski | 2026-04-21 15:59:01


VIEW MORE