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Engine Need help 90 mustang carbed 5.0

  • Thread starter Thread starter logonhappy
  • Start date Start date May 28, 2021
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    2.3 to 5.0 carb 302 fox body
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logonhappy

Member
May 28, 2021
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mn
May 28, 2021
#21
  • May 28, 2021
  • #21
another thing I forgot to mention my timing is still set good but my timing chain has a bunch of slop in it right now will be replacing that soon
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
7,387
2,745
194
Kearney, NE
May 28, 2021
#22
  • May 28, 2021
  • #22
If your timing chain jumps a tooth, it will run poorly all the time.
 
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logonhappy

Member
May 28, 2021
24
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mn
May 29, 2021
#23
  • May 29, 2021
  • #23
Well I checked my float levels today and surprised to see the bowls were completely filled above the sight plugs made a wonderful mess of fuel but they are set equally to where I slightly rock the car and I see fuel come out wondering if this makes sense of my problem? Thanks for responses
 
Reactions: LILCBRA

manicmechanic007

5 Year Member
Sep 26, 2017
2,534
714
143
Roy, Utah
May 30, 2021
#24
  • May 30, 2021
  • #24
logonhappy said:
I bought the car about 2 months ago maybe longer anyway factory 2.3 5 spd 90 mustang hatchback swapped to a 5.0 from a 84 truck carbed true dual exhaust no cats brand new holley street warrior carb electric choke anyways the problem runs fine until randomly under load motor starts bogging then dies have to pump throttle to get it started has no problem starting after u pump throttle couple times I've set my idle mixtures screws with a vaccum gauge got my idle set around 800rpm im thinking accelertor pump needs adjusting or float bowls aren't filling up all the way please any help appreciated sorry am new here not sure if I should post here or not thanks tho
Click to expand...
Check for sticking needles and seats in your Holley. Use non alky gas or install steel needles then recheck symptom. Used to just dry them out. Under warranty we used to take the sticking needles out of one GT mustang and replace them with new ford ones. Then next week when another mustang came in with the same problem we could lust use last weeks needles to fix this weeks mustang. We had so much trouble with the needles sticking, parts could not keep enough needles in stock. Finally figured it out that steel alky needles were the fix. Viton Smighton . I use steel ones in mine to this day. The alky needles also have a bigger window which lets more fuel in quicker. In case you are going racing like me. 6-502-2 is one Holley part number for the .120 seat ones. I do not remember them making three sizes, maybe look for the .097 ones
 
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logonhappy

Member
May 28, 2021
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mn
Jun 3, 2021
#25
  • Jun 3, 2021
  • #25
Well I might of figured it out today I went through and readjusted the whole carb floats choke idle idle mixture everything and I decided to screw my idle mixture screws all they way tell they barely touch and the one on the passenger side was like too turns farther out and the first time I set them I just trusted holley them saying its set close out of the box 2 turns off on one side isn't close sorry so reset everything and it idles way better and before u could hear a slight misfire every so often out the exhaust its gone now haven't drove it yet but running way better all together so will test drive it and let u guys know thanks again everybody still have to get a regulator just don't know which one I want to get
 
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logonhappy

Member
May 28, 2021
24
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mn
Jun 6, 2021
#26
  • Jun 6, 2021
  • #26
Well I am back sorry took so long but problem is still occurring carb is all set right good fuel pressure installed a inline spacer and also a carb spacer and heat isolator gasket because I determined it is vapor locking well turns out its not in the carb its somewhere in the line from the tank to the mechanical pump up to the inline filter which then is like 3 or 4 inches from my carb because I just tested it today and it stalled pushed it across the street into a parking lot cause it wouldn't start this time low and behold inline filter empty got a tow a couple blocks to my buddies house and got there and let it sit for an hour starts right up after line builds fuel up again im not sure what to do do I run all new rubber line instead of steel or what I new it was gonna be a stupid reason but not how to fix it I was thinking coil but I wouldn't think that would cause no fuel in the filter and recommendations appreciated thanks guys
 

7991LXnSHO

wanna catch the space herp
10 Year Member
Sep 1, 2010
7,387
2,745
194
Kearney, NE
Jun 6, 2021
#27
  • Jun 6, 2021
  • #27
A soft fuel line is a dangerous line. Last time I had a carb car get a track safety inspection, there was a maximum length of hose used limit.
Check for places where the exhaust and fuel lines are close. I have used DEI heat shield to keep fuel line after the fuel pump to the carb cool. It should help before the pump if the exhaust and fuel line cannot be moved apart. I think they and other places make heat shield that is sewn to side over the line and other that golds over and is held together with Velcro.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
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polk county florida
Jun 6, 2021
#28
  • Jun 6, 2021
  • #28
logonhappy said:
Well I am back sorry took so long but problem is still occurring carb is all set right good fuel pressure installed a inline spacer and also a carb spacer and heat isolator gasket because I determined it is vapor locking well turns out its not in the carb its somewhere in the line from the tank to the mechanical pump up to the inline filter which then is like 3 or 4 inches from my carb because I just tested it today and it stalled pushed it across the street into a parking lot cause it wouldn't start this time low and behold inline filter empty got a tow a couple blocks to my buddies house and got there and let it sit for an hour starts right up after line builds fuel up again im not sure what to do do I run all new rubber line instead of steel or what I new it was gonna be a stupid reason but not how to fix it I was thinking coil but I wouldn't think that would cause no fuel in the filter and recommendations appreciated thanks guys
Click to expand...
Did you type that all in one breath?
Your fuel pump may be getting hot and by passing, I would look into possible installing a in tank pump, they last longer.
 
S

slow84lx

clean it good before insertion
Jul 3, 2005
372
180
63
Dallas, TX
Jun 6, 2021
#29
  • Jun 6, 2021
  • #29
Check your ignition if you haven't already done so. Are you running a distributor for a carb application?
 
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logonhappy

Member
May 28, 2021
24
3
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mn
Jun 7, 2021
#30
  • Jun 7, 2021
  • #30
I moved my fuel lines the best I could no help mostly steel line only about 6 inches going to the carb which is new line and short peices connecting the tank supply and return lines to the pump which are also new when I put the motor back in fuel pump is basically new did it right before I got the car thinking the pump went out but the 351w cam lobe was free spinning for the fuel pump but thats fixed now new sending unit and short peices of rubber hose there tank vent is working so my next thing i guess is slide some insulation over the lines and see if that works
 
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logonhappy

Member
May 28, 2021
24
3
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mn
Jun 7, 2021
#31
  • Jun 7, 2021
  • #31
slow84lx said:
Check your ignition if you haven't already done so. Are you running a distributor for a carb application?
Click to expand...
Distributor is correct and I was thinking coil but how would that cause my inline fuel filter to be totally empty I couldn't figure that part out unless I'm totally spacing something out
 
F

Flyboy60

20+ Year Stangneter
Dec 11, 2004
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Sep 3, 2022
#32
  • Sep 3, 2022
  • #32
Any update after all this time ?
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,924
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polk county florida
Sep 3, 2022
#33
  • Sep 3, 2022
  • #33
Flyboy60 said:
Any update after all this time ?
Click to expand...
he was only around a few months, nothing after Aug 2021
 
F

Flyboy60

20+ Year Stangneter
Dec 11, 2004
115
35
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Sep 3, 2022
#34
  • Sep 3, 2022
  • #34
WOW
Sad - I was interested in the solution
 
S

slow84lx

clean it good before insertion
Jul 3, 2005
372
180
63
Dallas, TX
Sep 3, 2022
#35
  • Sep 3, 2022
  • #35
Perhaps he will get an email notification of new post and it may remind him.
 

General karthief

wonder how much it would cost to ship you a pair
20+ Year Stangneter
Aug 25, 2016
27,924
10,572
203
polk county florida
Sep 3, 2022
#36
  • Sep 3, 2022
  • #36
Flyboy60 said:
WOW
Sad - I was interested in the solution
Click to expand...
You have a thread stating your problem?
 
F

Flyboy60

20+ Year Stangneter
Dec 11, 2004
115
35
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Sep 3, 2022
#37
  • Sep 3, 2022
  • #37
Not at the moment. Just curious
I will have tons once I start the 4 Cylinder conversion.
 
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