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5/21/2022 12:08 PM  #1


59 352 Idling issue

1959 Bird with a 352, can't get to idle. Starts OK but takes a few times to get it to run, once I get it running I have to keep it revved up to keep it running. Drop below 1100 or 1200 RPM and it stalls immediately. Try to adjust down to 750-800 and it stalls. Put it in drive at 1000 rpm it stalls. This has an Edelbrock 4 barrel carb and pertronix ignition. Cleaned plugs, changed the fuel filter. Seemed to have dirt in hand when I changed filter, not sure if it came from the gas in the filter or handling a dirty hose. Hope i don't need a new tank. It did run a little better after filter change. The filter don't seem to fill up. One other thing the choke don't seem to make much difference but to much choke, it will stall. Anyway next step was to rebuild carb and or new fuel pump. Any other thoughts would be apricated. 


If this forum can't fix it, it isn't broke.
 

5/21/2022 11:38 PM  #2


Re: 59 352 Idling issue

Vacuum leak somewhere? Old gas? Idle mixture set correctly with vacuum gauge? Water or trash in the carb bowl?


68 coupe - 351W, 4R70W, 9" 3.25 -- 65 convertible - 289 4v, C4, 8" 3.00
 

5/22/2022 6:44 AM  #3


Re: 59 352 Idling issue

The immediate stall is what gets me.  If its a fuel pump issue the pump can't be filling the float bowl or it wouldn't stall immediately.  It would run on the gas in the bowl for a short while. 

I would tend to suspect a vacuum leak first.  It needs a high idle to avoid a stall (to get around the leak).  You put a load on it and it stalls (because of the leak).  Tough to diagnose these things over the internet, kind of like trying to give you a haircut over the phone, but based on what you're saying I'd start by checking for vacuum leaks. 
 

 

5/22/2022 7:30 AM  #4


Re: 59 352 Idling issue

I was thinking vacuum leak too. Were any of the plugs oily? Sometimes the intake gasket fails creating a vacuum leak and oil consumption.


John  -- 67 Mustang Coupe 390 5 speed
 

5/22/2022 8:57 AM  #5


Re: 59 352 Idling issue

Vacuum issue is my thought also, then check the fuel pump pressure.  Check all the vacuum hose lines, they may have cracked, etc. due to age (?).
I had a daily driver that had rust in the tank, when the fuel filter would clog up, it impacted driving at speed, not at idle. 


65 Fastback, 351W, 5-speed, 4 wheel discs, 9" rear,  R&C Front End.
 

5/22/2022 9:52 AM  #6


Re: 59 352 Idling issue

The sudden stall kept eating at me so I ordered a fuel pump, didn't notice much gas in the filter. Will check for vacuum leaks also. Been down last few days sick, we tested positive for COVID with a home test for what it's worth. Getting back at it. Ron would like more info on setting cab with vacuum gauge if you have it, Thanks for all responses!


If this forum can't fix it, it isn't broke.
     Thread Starter
 

5/22/2022 12:02 PM  #7


Re: 59 352 Idling issue

wsinsle wrote:

The sudden stall kept eating at me so I ordered a fuel pump, didn't notice much gas in the filter. Will check for vacuum leaks also. Been down last few days sick, we tested positive for COVID with a home test for what it's worth. Getting back at it. Ron would like more info on setting cab with vacuum gauge if you have it, Thanks for all responses!

This might help - there are lots of videos on youtube to help with carb tuning
https://www.youtube.com/watch?v=_AgqTUJr8aM
Good luck.
 

Last edited by Ron68 (5/22/2022 12:08 PM)


68 coupe - 351W, 4R70W, 9" 3.25 -- 65 convertible - 289 4v, C4, 8" 3.00
 

5/22/2022 1:56 PM  #8


Re: 59 352 Idling issue

Advance timing.  What is the compression?  Need to establish baseline, or you are just guessing


Money you enjoy wasting is NOT wasted money... unless your wife finds out.
 

5/22/2022 4:39 PM  #9


Re: 59 352 Idling issue

What is history on Eddy carb?
Has it been sitting a while?

Might want to pull top off and see if varnish sloughed off the fuel bowl.
Happened to me after getting it running well.
Car was pretty much a garage art for several years before.

As for the fuel tank, I pressure washed inside the gas tank on the El Camino with great results.
This was a Texas truck and all gas had evaporated and it looked like dried cracked mud.
Tank was still solid, minor rust but still useable for a driver.

I heard about this technique at a welding shop that usta boil out radiators.

 

5/22/2022 5:11 PM  #10


Re: 59 352 Idling issue

You KNOW how to check for vacuum leak...... That's my guess.
You replaced the fuel pump so that woulda  been next.
Is the tank original (or do ya know?)
Take the top off the carb........be careful and save-the-gasket.....(don't lose the little cotter pin on the accel. pump arm!!)
Spray the inside really good with Brakleen (I love that stuff!) I wouldn't think a re-build kit would be needed they are so simple.
What's your initial timing set at?
6sal6


Get busy Liv'in or get busy Die'n....Host of the 2020 Bash at the Beach/The only Bash that got cancelled  )8
 

5/23/2022 4:58 AM  #11


Re: 59 352 Idling issue

Worth noting that if you are going to monkey with timing make sure that TDC on the balancer is actually TDC.  If the outer ring moved, etc. the timing marks can be off. 

 

5/23/2022 8:11 AM  #12


Re: 59 352 Idling issue

My bet goes to the idle mixture adjustment.
Or
When you start the engine and it runs 1100rpm, close the choke plate  slowly with your hand. If engine runs you have a vacuum leak somwhere.

My 2 cents

Mustsed
 

 

6/04/2022 12:42 PM  #13


Re: 59 352 Idling issue

Update: After putting on a tach found it was actually cutting out when dropping below 1600 RPM. Put a pressure gauge on the fuel line and read a good 4.5, I never changed the fuel pump. Checked for vacuum leak around the base of the carb with starter fluid spray, no leak there. Opened up the top of carb, gunk inside both bowls. Rebuilt the carb, same issue. Had a can of premium gas, put a hose from the fuel pump to the can. Run for a while still no change. Put a charger on the battery, batt a little low due to so many starts. Had a beer then another then another, proof beer solves problems. Plugged all vacuum lines coming off the manifold. Started the car, running good. Turned idle down to 800, purring like a kitten. Hooked the gas line back up still running good. Connected vacuum lines 1 at a time, all connected still running good. WTF Took a few rides that night, a few misses on the hills, but ran good. Next day went to fine tune things, would not run below 1600. Beat my head off the brick wall a few times for fun, started drinking early. Tried fresh gas again because everyone knows when you do the same thing twice you get different results. Not this time still doing the same thing. Started thinking, probably the beer, but sometimes when starting I had to hold on the key to start an extra second or so to get it to run. Put a jumper from Batt to coil +, started good and ran idle down to 800, still good. Started some electrical checks. Seems to be a charging issue, seem to be charging but never gets to 13 volts. May have a bad connection on the resister wire, should run below 1600 even if I'm only getting 12 volts at the battery. At least I know where to look now. Hopefully have the dents in my head fixed before the next bash.


If this forum can't fix it, it isn't broke.
     Thread Starter
 

6/04/2022 6:56 PM  #14


Re: 59 352 Idling issue

wsinsle wrote:

Update: After putting on a tach found it was actually cutting out when dropping below 1600 RPM. Put a pressure gauge on the fuel line and read a good 4.5, I never changed the fuel pump. Checked for vacuum leak around the base of the carb with starter fluid spray, no leak there. Opened up the top of carb, gunk inside both bowls. Rebuilt the carb, same issue. Had a can of premium gas, put a hose from the fuel pump to the can. Run for a while still no change. Put a charger on the battery, batt a little low due to so many starts. Had a beer then another then another, proof beer solves problems. Plugged all vacuum lines coming off the manifold. Started the car, running good. Turned idle down to 800, purring like a kitten. Hooked the gas line back up still running good. Connected vacuum lines 1 at a time, all connected still running good. WTF Took a few rides that night, a few misses on the hills, but ran good. Next day went to fine tune things, would not run below 1600. Beat my head off the brick wall a few times for fun, started drinking early. Tried fresh gas again because everyone knows when you do the same thing twice you get different results. Not this time still doing the same thing. Started thinking, probably the beer, but sometimes when starting I had to hold on the key to start an extra second or so to get it to run. Put a jumper from Batt to coil +, started good and ran idle down to 800, still good. Started some electrical checks. Seems to be a charging issue, seem to be charging but never gets to 13 volts. May have a bad connection on the resister wire, should run below 1600 even if I'm only getting 12 volts at the battery. At least I know where to look now. Hopefully have the dents in my head fixed before the next bash.

You've tried a lot, but I don't see where you adjusted the idle mixture.  Adjusting the idle speed it something you do after you have properly set the mixture adjustment and the engine is at normal operating temperature. Smooth running at temperature and idling under a load with an rpm that will keep the alternator charging the battery is what you are looking for. Keep at it!
 


68 coupe - 351W, 4R70W, 9" 3.25 -- 65 convertible - 289 4v, C4, 8" 3.00
 

6/05/2022 5:06 AM  #15


Re: 59 352 Idling issue

I think you've ruled out a fuel system issue.  It seems like you have an intermittent vacuum leak.  My guess is moving the lines around when you were working on it temporarily closed the leak, but over time and with a good heat cycle it reappeared.  My thought would be replace all the vacuum lines and see if the problem resolves. 

On the charging, given its age I'd say it has a generator, not an alternator.  If that's the case, generators don't put out the same kind of voltage as an alternator.  With an alternator we are used to seeing 14+ volts, but generators may only put out 13+ volts.  I wold consider anything below 13.2 volts to be a sign of low output.  But if you're seeing 13.5 that's healthy output.  If the battery is still running down, or loosing charge overnight I'd say the issue is the battery, not the generator.  One quick test is charge the battery and see what you get.  Fully charged it should read 12.6 volts or thereabouts.  Put a voltmeter on it and crank the car and see what the voltage drops to when you throw a load on it.  If it gets down to below 10.5 volts the battery is failing.  You could try desulphating it to see if its just the result of sitting.  That might bring it back.  If not its new battery time.

The missing when driving may be the result of old ignition components.  I'd throw a general tune up on it (plugs, wires, cap, rotor, points & condenser if equipped).  If that doesn't solve it you may have a bad valve to seat seal.  I've seen a handful of FEs over the years with burned exhaust valves.  Not sure if this is common on FEs per se, or just my experience, but as a last thing to check its worth thinking about. 
 

Last edited by TKOPerformance (6/06/2022 2:02 PM)

 

6/06/2022 7:55 AM  #16


Re: 59 352 Idling issue

TKOPerformance wrote:

I think you've ruled out a fuel system issue.  It seems like you have an intermittent vacuum leak.  My guess is moving the lines around when you were working on it temporarily closed the leak, but over time and with a good heat cycle t reappeared.  My thought would be replace all the vacuum lines and see if the problem resolves. 
 

I agree, change all the vacuum lines, one, or more, may be dried out and leaking intermittently.  I had a similar issue with a Dad’s car many years ago (a late seventies Olds), couldn’t find the issue, was recommended to change all the vacuum lines (which there were many), problem went away. 

 


65 Fastback, 351W, 5-speed, 4 wheel discs, 9" rear,  R&C Front End.
 

6/06/2022 7:14 PM  #17


Re: 59 352 Idling issue

BobE wrote:

TKOPerformance wrote:

I think you've ruled out a fuel system issue.  It seems like you have an intermittent vacuum leak.  My guess is moving the lines around when you were working on it temporarily closed the leak, but over time and with a good heat cycle t reappeared.  My thought would be replace all the vacuum lines and see if the problem resolves. 
 

I agree, change all the vacuum lines, one, or more, may be dried out and leaking intermittently.  I had a similar issue with a Dad’s car many years ago (a late seventies Olds), couldn’t find the issue, was recommended to change all the vacuum lines (which there were many), problem went away. 

 

OR.......just plug all but the vacuum advance to the distrib. (IF legal in your state)
6sal6
 


Get busy Liv'in or get busy Die'n....Host of the 2020 Bash at the Beach/The only Bash that got cancelled  )8
 

Board footera


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