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Need Help! Car wont start after Carb Conversion...long

  • Thread starter Thread starter 91FrankinStang
  • Start date Start date May 26, 2005
9

91FrankinStang

New Member
May 15, 2005
22
0
0
May 26, 2005
#1
  • May 26, 2005
  • #1
Did a Carb & T5 conversion on my '91GT. Installed an MSD 6A w/ blaster 2 Coil, '85 GT dizzy, performer 289 intake, brand new Holley 600 Carb, Holley Blue pump w/ Mallory Bypass Regulator.. Removed computer, harness & smog..

What is happening is I am getting popping/backfiring from the exhaust, AND the carb.. The carb spits fuel, like its flooding real bad.. When I remove the aircleaner, there is a nice cloud of gas that comes up.. But no flames have come up from the carb.. And every once in awhile i get backfire from the exhaust..

To set timing, i removed #1 spark plug, had someone bump over the motor till it blew my finger out of the spark plug hole.. Check the mark on the balancer and its close to BTDC.. I turn the motor by hand to 10* BTDC. lift dizzy enough to turn rotor till it drops in with the rotor pointing to the #1 spark plug.. Snug dizzy, reinstall spacer & cap.. Verify correct firing order and it is counter clockwise..

To my knowledge & experience, it should start at that point.. ITs cranking and it sounds like it wants to start, but it just doesnt.. But its close..

Now, to the fuel system.. Originally, I had the regulator that came with the blue pump. i never installed a fuel pressure guage b/c for that reg., the pressure is preset.. Now, I had to switch to the bypass b/c the holley reg was no good for a return style system.

But, being I have no fuel pressure guage ,I dont know what my pressure is and if it is too much.. I think it is getting too much pressure.. I have tried tightening and loosening the adjustment screw a number of times with no luck..

Checked timing like 3 times..

I removed to sight plug on the carb to check float level, and fuel poured out indicating it could be too high.. But then again, if it was getting too much pressure, wouldnt the bowls constantly be full and then of course fuel will come out when i remove the plug??

Can someone explain the correct way in detail to check float level?? car on or off,etc..

Also, is anyone familiar with this regulator and know if the pressure could be set w/out a fuel pressure guage?? like say, bottom out the screw, then back it out 3 turns.. that should be 7psi.. just for example.. Or must i have a guage to adjust the pressure..?

If I need to guage, Summit sells one that will connect directly to the banjo fitting on my carb.. Its is made by Segis..or something.. will this be ok for what I need?? I really dont wanna go cutting fuel line to splice ina guage b/c it is all braided line and a PITA.. but, if i gotta.. i gotta..

The model of the carb is 80457S.. It is brand new out of the box.. Nothing has been touched, except the float level which i lowered a little..

Any ideas on whats going on???


Also, aftet i stopped cranking when I was trying to start it, I looked down the carb and fuel was dripping out of the jets.. What does that indicate???

I also pulled plugs and they were not soaked/fouled..

Any help a/s/a/p appreciated.. I'd really like to get this thing running tomorrow..

Joe
 
N

nickg42oz

Founding Member
Dec 16, 2000
358
0
16
New Orleans, LA
May 26, 2005
#2
  • May 26, 2005
  • #2
I had a similar problem and it ended up being some valves were adjusted to tight.
 

The Fox

New Member
Mar 30, 2005
354
0
0
Port Elizabeth
May 26, 2005
#3
  • May 26, 2005
  • #3
All gaskets are good? Make Sure the idle screw is backed down pretty low. Umm, make sure no plug wires are crossed, definately take a look at that fuel pressure, check vaccum lines... eh i dunno.

Not a solution at all. Just if I had your probs that's all the crap I would look at. ALSO, exhaust leaks can cause some of your "ailments."
 

85 Capri

New Member
Aug 18, 2004
8
0
0
GTA, Canada
May 27, 2005
#4
  • May 27, 2005
  • #4
You really need a fuel pressure gauge! It sounds like your regulator is set too high, this forces fuel past the needle and seat and you get flooding! A holley blue runs around 15psi, holley carbs are only going to take 7psi then the pressure will force the needle off the seat, gas will fill up the bowls and run out the vent tubes and all kinds of places!!

Also, level is checked with the car running, pull the site plug and fuel should *just*trickle out as the engine shakes! The rear could be a tad bit higher, but not running out!
 

Stang8URMPRT

Active Member
Dec 28, 2003
1,100
1
38
Daytona Beach, FL
May 27, 2005
#5
  • May 27, 2005
  • #5
Yep, you really need a f/p gauge... I didn't read the whole thing cause it's too long for my A.D.D. lol... But hell... a carb needs an ignition, like an MSD with uhhh... power, ground, and ignition on... two wires to the dist, and two to the coil... Not too hard. Should fire right up as long as the pump is working and you're actually getting fuel. Even if it's too much pressure, it should still fire, and maybe die. You can push the needle from teh seat and screw it up pretty good. Turn the pump on, open the butterflies and check to make sure you're squirting fuel in there. Good luck man!
 
9

91FrankinStang

New Member
May 15, 2005
22
0
0
May 27, 2005
#6
  • May 27, 2005
  • #6
thanks... I'm gonna try an find a guage locally today and install it & see what happens.. if not gotta order from summit..

If it still doesnt start once the pressure is right, then i guess it is timing related..
 
T

tony91723

Member
Nov 30, 2004
71
0
7
May 27, 2005
#7
  • May 27, 2005
  • #7
yep I would have to agree as well with stang8. I have a question for you did you use the stock efi fuel pump? and that is why you are running the after market fuel pressure regulator thanks.
 
9

91FrankinStang

New Member
May 15, 2005
22
0
0
May 28, 2005
#8
  • May 28, 2005
  • #8
no. i am using a holley blue electric fuel pump.. I removed the stock pump & pickup assembly and used a grantielli motorsports fuel tank insert.

I'll be getting the guage on by the end of the week so hopefully it'll work out. I found a fitting I can use in Jegs w/out having to cut any lines.. It has a 3/8" female & 3/8" male & 1/8" port.. I will unscrew my lines going to the carb from the regulator, screw in this fitting, then screw in the line going to the carb into the female side, and the guage into the 1/8 port..

Should work with no probs..

thanks again
 

NOSNotch

Founding Member
Oct 20, 2001
577
0
0
South Jersey
May 29, 2005
#9
  • May 29, 2005
  • #9
91FrankinStang said:
To set timing, i removed #1 spark plug, had someone bump over the motor till it blew my finger out of the spark plug hole.. Check the mark on the balancer and its close to BTDC.. I turn the motor by hand to 10* BTDC. lift dizzy enough to turn rotor till it drops in with the rotor pointing to the #1 spark plug.. Snug dizzy, reinstall spacer & cap.. Verify correct firing order and it is counter clockwise..
Click to expand...


When you bumped the motor over til it blew out #1 you shouldnt have really had to turn the motor. Did you drop the distributor in with the 0 line on your balancer centered in the round hole on your timing pointer? That would be the first thing id check and definitely gotta get a fuel pressure gauge on there. good luck with it

kevin
 

08GT500

5 Year Member
Jul 12, 2018
918
140
63
Massachusetts
Aug 31, 2018
#10
  • Aug 31, 2018
  • #10
Are you 100% that you’re using the CORRECT firing order’for the Motor and CAM that’s in the Car? That can change the firing order, depending on the year Cam..That sounds like an Ignition or Valve timing issue, as previously said- Valves hanging up..Cheers!
 

billison

I like tinted tail
15 Year Member
Feb 27, 2006
2,607
1,094
184
stl
Aug 31, 2018
#11
  • Aug 31, 2018
  • #11
08GT500 said:
Are you 100% that you’re using the CORRECT firing order’for the Motor and CAM that’s in the Car? That can change the firing order, depending on the year Cam..That sounds like an Ignition or Valve timing issue, as previously said- Valves hanging up..Cheers!
Click to expand...
This was like... 13 years ago... I’m guessing he got it. I hope
 
Reactions: 08GT500 and jrichker

08GT500

5 Year Member
Jul 12, 2018
918
140
63
Massachusetts
Sep 1, 2018
#12
  • Sep 1, 2018
  • #12
billison said:
This was like... 13 years ago... I’m guessing he got it. I hope
Click to expand...
Thank you for that, billison. Ummm..OK. My bad- I’d looked for unanswered and recent threads.. Wonder what the right answer to correct the issue turned out to be?
 

billison

I like tinted tail
15 Year Member
Feb 27, 2006
2,607
1,094
184
stl
Sep 1, 2018
#13
  • Sep 1, 2018
  • #13
08GT500 said:
Thank you for that, billison. Ummm..OK. My bad- I’d looked for unanswered and recent threads.. Wonder what the right answer to correct the issue turned out to be?
Click to expand...
No clue. I wish people would make a effort to post the conclusion in posts like this.
 

08GT500

5 Year Member
Jul 12, 2018
918
140
63
Massachusetts
Sep 1, 2018
#14
  • Sep 1, 2018
  • #14
billison said:
No clue. I wish people would make a effort to post the conclusion in posts like this.
Click to expand...
billison said:
No clue. I wish people would make a effort to post the conclusion in posts like this.
Click to expand...
Yes,, agreed. After people are willing to help, & the issue is correctly diagnosed, people just forget to take the time to say “Thanks” (think how much time was saved by using this Site, they’d likely still be stumped)., and/or reveal what suggestion(s) were helpful, helping those involved, and possibly another down the line with a similar issue. Might be a useful Guideline, to officially close a Suject with the conclusion by the one who created it..
 
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