Engine 1966 Mustand straight 6

sarabrierton

New Member
Aug 17, 2019
1
0
1
20
Flower Mound, Tx
I let my '66 sit for about a month and a half, and now she's sputtering while accelerating. I'm getting a really bad gas smell, but she's not leaking at the filter or fuel pump or carb. I replaced the filter thinking it might help - and it did for all of a few days. What's causing this and how can I fix it?
 
  • Sponsors(?)


08GT500

Active Member
Jul 12, 2018
703
95
38
Massachusetts
:potroast:Hi,
More of a 289 Guy, love the I-6’s, however. I’ll target this general old school. If burning your eyeballs out at idle & it was a Holley, I’d say power Valve, takes one ‘pop’ & it’s done for...but consider/test for these:
Caution: I’ve lost my eyebrows (need a GIF for this on SN, Wile E. Coyote?) more than once over a Carb/Carb(s), err..Pic above is pretty appropriate. Use care when observing inside Carb, throttling while running....
1)Moisture under the Dizzy Cap, take a peek that all is clean & otherwise well.
2)Running on all 6 Cylinders. Spare wires kicking around?
3) Choke sticking, hanging up, pulled in under acceleration..
4) Accelerator pump issue, leaking out around the squirter instead of through it.
5) Is fuel leaking internally through the overflow tube & being burned?, stuck Carb Float.
6) What is your Fuel Pressure at the Carb?(5-7lbs).
7) Vacuum Advance line crack, diaphragm rupture, or mech advance issue in Dizzy.
8) Coil (+/-) connections, Check all wires are seated well in the Cap, run in dark conditions to see Coil secondary arc’s between wires & Cap, wire to wire, may be able to hear it if Exhaust is quiet, etc.
9)May be a clogged line from Tank, limiting fuel sporadically to your mechanical pump. Quick Dx is Carefully pull the tank line off the pump, stick a 3/8” line on the Pump into a 5 Gallon gas can & see how she runs...Damp rag around where it enters the can to keep fumes down.
Good luck!
-John
 
  • Like
Reactions: 2Blue2

08GT500

Active Member
Jul 12, 2018
703
95
38
Massachusetts
Hi,
Really nd. to work on condensing things, lol. Wanted to add, while in the Dizzy, anyways- & still running Breaker Points, clean them with a piece of Sandpaper (Or sneak off with your Girls nail file, they’re viscous about this, careful!).
240-320 Grit doubled over, points open, wedge the paper/File between, run back & fro to clean both surfaces, minimal material removed. Blast sediment away, check your gap, [email protected] 0.025-0.027. If your points are really pitted, likely a bad Condensor. Still sell replacements!
Check/Set your Dwell if you have a meter, remote Starter & you’re feelin’ Faaancy!
Now, set your Dynamic Timing.
Hope this is useful, good luck!
-John
 
  • Like
Reactions: GOvert and 2Blue2
Thread starter Similar threads Forum Replies Date
A 1966 i6 steering/suspension help 1965 - 1973 Classic Mustangs -General/Talk- 5
R Can someone tell me Approximate Build date from Vin production # on my 1966 2+2? 1965 - 1973 Classic Mustangs -General/Talk- 1
H over heating on 1966 mustang Classic Mustang Specific Tech 3
A Engine Need Help Finding a Part Classic Mustang Specific Tech 1
R 1966 Mustang Coupe Wiring 1965 - 1973 Classic Mustangs -General/Talk- 2
R 1966 Mustang Brake Issues 1965 - 1973 Classic Mustangs -General/Talk- 9
R 1966 Coupe Radio Wiring 1965 - 1973 Classic Mustangs -General/Talk- 0
A 1966 Coupe Slow Build 1965 - 1973 Classic Mustangs -General/Talk- 21
N Need Help With 1966 Mustang Heater Problem Classic Mustang Specific Tech 8
R 1966 Coupe Wiring Question 1965 - 1973 Classic Mustangs -General/Talk- 0
S Thermal clutch fan recommendations for 1966 Mustang w/ 289 1965 - 1973 Classic Mustangs -General/Talk- 1
6 Biggest rear tire stock height 1966 Mustang??? 1965 - 1973 Classic Mustangs -General/Talk- 0
M Will a Mustang radio made for a 1964 - 1966 Mustang Stereo 1965 - 1973 Classic Mustangs -General/Talk- 7
R 1966 1965 - 1973 Classic Mustangs -General/Talk- 2
wicked93gs 1966 Mustang Coupe: Ford 3.7L swap 1965 - 1973 Classic Mustangs -General/Talk- 10
Z building a 1966 mustang straight 6 200ci on a budget Classic Mustang Specific Tech 3
M In Tank Pump for 1966 EFI Conversion-1973 tank? Classic Mustang Specific Tech 2
wicked93gs Offbeat project: 1966 Coupe 1965 - 1973 Classic Mustangs -General/Talk- 4
wicked93gs Swapping a 3.7L v6 into my 1966 Mustang, looking for a bit of ECU info 2005 - 2014 Specific V6 Tech 10
S WTB/Trade Need AC unit for 1966 Mustang convertible Interior Exterior Parts 0
M Questions about putting a 4.6 into a 1966 1965 - 1973 Classic Mustangs -General/Talk- 28
B 1966 289 Mustang Overheating 1965 - 1973 Classic Mustangs -General/Talk- 8
W 1966 mustang 289 Balance mystery Classic Mustang Specific Tech 10
N 1966 mustang rear axle 1965 - 1973 Classic Mustangs -General/Talk- 2
R My new 66 mustang 1965 - 1973 Classic Mustangs -General/Talk- 5
D 1966 carpet color 1965 - 1973 Classic Mustangs -General/Talk- 4
K For Sale Translucent Red 1966 Ford Mustang GT350 For Sale! Classic Mustangs For Sale 0
S 1966 neutral safety switch vs transmission issue? Classic Mustang Specific Tech 3
R For Sale Classic 1965GT 1966 Mustang gauges Interior Exterior Parts 0
S 1966 Shelby 10 spoke wheels. Real? 1965 - 1973 Classic Mustangs -General/Talk- 4
S New 1966 fastback owner! The Welcome Wagon 6
S 1966 Mustang thermactor filter 1965 - 1973 Classic Mustangs -General/Talk- 4
robthechemist Excited to join! New Guy in California- 1966 coupe/ 302 swap- 4 speed toploader The Welcome Wagon 13
VOORHEES Family owned 1966 C-code Fastback soon to be out for restoration. PICS ADDED! 1965 - 1973 Classic Mustangs -General/Talk- 3
K New to me 1966 convertible 1965 - 1973 Classic Mustangs -General/Talk- 2
E mustang 1966 Oil in intake Classic Mustang Specific Tech 7
R My 1966 coupe 1965 - 1973 Classic Mustangs -General/Talk- 7
R 66 Front disc brake conversion, Did a search and couldn't find an answer 1965 - 1973 Classic Mustangs -General/Talk- 4
F 1966 mustang buck tag info 1965 - 1973 Classic Mustangs -General/Talk- 0
A 1966 Mustang Help 1965 - 1973 Classic Mustangs -General/Talk- 1
A Engine Trouble 1965 - 1973 Classic Mustangs -General/Talk- 4
M Engine 1966 backfire through carburetor Classic Mustang Specific Tech 4
Sweetmarie66 1966 I-6 head conversion Classic Mustang Specific Tech 2
WarHorse66 1966 straight 6 harmonic balancer removal help!! 1965 - 1973 Classic Mustangs -General/Talk- 3
Paxton.5oh 1966 - Replacement Side Mirrors Classic Mustang Specific Tech 0
S 1966 mustang 1965 - 1973 Classic Mustangs -General/Talk- 1
I 1966 289V8 timing/bent push rods? 1965 - 1973 Classic Mustangs -General/Talk- 5
H 1966 Mustang 289 flywheel info needed Classic Mustang Specific Tech 7
M 1966. 289 compresśion is dropping Classic Mustang Specific Tech 8
D 1966 manual bell housing 1965 - 1973 Classic Mustangs -General/Talk- 2
Similar threads