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Leaking CARB

 
Raulh
New User
Posts: 37
Joined: 09/09
Posted: 09/09/12 07:55 AM

Hi,all.
I have a 1968 Mustang that is leaking gas from a Carb gasket. I changed the intake manifold gasket (the one that is between the spacer and manifold) because it was leaking, I also took off the gasket form the carb that attaches to the top of the spacer that sits on top of the manifold. I replaced the bottom gasket (intake Manifold) but not the one to the carb spacer looked good. well it leaked when I put fuel from the top and noticed that when I manualy pumped the carb that no stream of fuel was going in. The car starts when fuel is putted in and remains started. And starts shortly after. I checked the fuel pump and it seems to be putting out fuel (disconnected and cranked fuel in a bottle). It seems that the float might be stuck or this leak is causing the problem?

Thanks in Advance
Raul  

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waynep71222
User
Posts: 58
Joined: 04/12
Posted: 09/09/12 07:52 PM

you did not say which carb you have..

you could have several issues....

#1.....     Reddish dUST in the fuel..  this gets in the fuel pump check valves.. also clogs the fuel filter again and again if you have a decent brand filter at the carb... but the particles are so small.   that they get through the filter and stain the bottom of the float bowl reddish..

the Reddish dUST will hold the needle and seat open slightly.. allowing the residual fuel volume held by the pump to weep through .. overfilling the float bowl.. the fuel trickling out of the booster venturis drips onto the closed throttle blades... follows the throttle shaft through the side of the carb and drips onto the intake...  sometimes.. it follows the throttle shaft and drips down the base and seems to come out of the mounting gasket..  it varies on how much the throttle shaft bore is worn..

the fix...

stick a big speaker magnet to the bottom outside of the fuel tank.. don't ever move it..   next time you have the sending unit out..  drop some super magnets into the bottom of the tank through the opening and verify they actually fell to the bottom... sneaky devils will fall sideways and stick to the side of the  tank.. or the inside of the opening..  they will attract all the loose Reddish dUST to them..  right through the floor of the tank if you only have the exterior magnet stuck on...

also... pick up a fuel injection type of fuel filter.. install it in a new section of fuel hose just before the fuel pump...

run the open fuel line test again into the bottle..   do it for 15 seconds.. while you watch the pulses... each one should be nice and full.. equal to the others..   they should not be diminishing..  clogged fuel lines have been an issue lately.. but you have already checked this.. but with the fuel filter installed just before the pump.. the full flow of FILTERED gasoline surging through the pump check valves will usually clean the crud out...


use a magnet to examine the fuel from this test.. .. you can just pour it back in the tank...

next.. hook the carb back up...  fire the engine up...  with a pair of pliers.. i use long  LONG nose pliers.. i pinch off the hose between the new filter and the pump...  this stops the fuel flow into the pump.. i then while holding the pliers.. bring the engine rpms up  to around 2500... and hold it there... as the fuel is used up in the carb and whats left in the fuel pump.. the engine will start to die... release the pliers...  this will instantly rush a massive amount of fuel through the pump.. and also through the wide open needle and seat...   i sometimes do this 2 or 3 times...

it really clears out the stuck junk in the needle and seat...

why this works when the fuel is cut off. the float level drops opening the needle and seat farther than it normally sees.. the instant rush of filtered fuel moves faster than normal through.. cleaning like a leaf blower as it flushes the junk right into the float bowl... but thats a better place for it..

try it.. i have fixed a LOT of cars this way.. cost.. under 20 bucks...  depending on the price of the magnets you use... 7 to 9 for a fuel injection type of fuel filter.. i have been using ones for 90 fords... just shoving the fuel hose over the long ends and clamping it on..  sometimes needing enough fuel line to make a loop for the fuel filter to fit..  

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pepsi1
New User
Posts: 36
Joined: 03/12
Posted: 09/09/12 07:58 PM

You said it Wayne.

What do you have. If you have an old Ford carb I can tell you this. Whenever you replace any gaskets on them just snug the screws down. If you overtighten them they leak, and will drive you crazy...

Bob  

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Raulh
New User
Posts: 37
Joined: 09/09
Posted: 09/10/12 11:44 AM

Thanks again for the quick reply!
I have a Motorcraft DOPF 9510K1 bbl, I think this is not the original carb if memory serves me it should be an Autolite 1100?
I tryed the starting the engine and pinching the fuel hose and let go before the engine dies three times. And all seemed good fuel injected into the carb when manually pumped as it should. Went to have dinner, after about 40 min I tryed to start the engine and again the same problem no fuel injecting like befor but this time I had a hard time starting the engine and when it got hot it would not remain on. I replaced the fuel filter with a new one, I did not mention this I have two fuel filters installed; I took off both filters and replace with one new filter and still the engine would not stay on. I thinking it may be the carb or possibly the fuel filter. The fuel filter is leaking oil from the round part that looks like it was pressed together and not where it is mounted to the engine. thinking it is on its last leg?
I think I will have a cold German beer or two a call it a day. Again Thanks Laugh  

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Raulh
New User
Posts: 37
Joined: 09/09
Posted: 09/10/12 11:52 AM

Bob,
Thanks again!
I was going to ask how tight and the Ford manual says to specs but could not find it in the manual. I have a Motorcraft DOPF 9510K 1 bbl.I think it should be an Autolite 1100? I am the third owner and have had problems with the carb since I had it (would not idle correctly and sputter). I only take the girl out in the summer. The German winter here and the salt is just to hard so she stays in a garage and is started every week.

Raul  

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pepsi1
New User
Posts: 36
Joined: 03/12
Posted: 09/10/12 12:42 PM

Raul:
You probably won't find torque specs on a carburator. Make sure all those mating surfaces are flat. If not the gaskets will never seal.

I had a 1964.1/2 Mustang K-Code 271/289... That had a big autolite/ford carb that leaked gas all the time..It was always a mess under the hood and smelled gas all the time.

I finally got pizzed and took the carb all apart...I went over every mating surface, and with a wet/dry 220 grit sand paper I put lite machine oil on the sand paper, and in a circular-8 pattern I got those mating surfaces as flat as I could. I reassembled the carb, and as the gaskets just touched the other parts. I went 1/2 turn more. Then when the engine got hot I went 1/4 to 1/2 turn more and I never had a problem with it after that.

One thing I did do under the head of the screws I used a flat washer, and on top of that I took a lock washer, and cut approx 1/32" off from the end, (SEE NOTE)and I never had fuel come from under the gaskets again.

(NOTE) This should have been before the assembly of the carburator. I cut the lock washer back so it would not have so much bite on the flat washer, and distort the flat washers...

I know it a lot of info to digest. But we can get you through it.

Bob  

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pepsi1
New User
Posts: 36
Joined: 03/12
Posted: 09/10/12 12:57 PM

Raul:

Have you tried spraying some carb clean over the top of the carb to keep the engine running. If it does keep running there could be a couple problems.

1.The fuel pump is losing its prime when you shut the engine off.

2.There maybe a leak in a fuel line along the floor of the car.
See if there are any wet spots on the under neath of the car.

3. The fuel pumps get lubricated by the engine oil. They also have a gasket under the fuel pump. That should be easy enough to replace.

4.If you have to replace the fuel pump there will be a gasket with the pump.

5.VERY IMPORTANT: WHEN WE GET YOUR CAR RUNNING I'LL PM YOU WITH MY ADDRESS SO YOU CAN SEND THE COLD GERMAN BEER THERE.....LOL....

Keep us posted as to your progress.

Bob  

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pepsi1
New User
Posts: 36
Joined: 03/12
Posted: 09/14/12 05:32 PM

Raul:

What you can do to hold those gaskets in place is get some of the hi tach gasket spray. Spray it on both sides of the gasket, let it get tacky and then put it in place..

Bob  

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Raulh
New User
Posts: 37
Joined: 09/09
Posted: 09/17/12 12:59 PM

Hi, been very busy with work but did do some work on the girl.
I replaced the fuel pump and the car starts better but the problem of not having any power is the same. I did not mention that I have a Pertronix ignition system installed (by the previous owner)and did some research on the web and they do have problem from hard starting... to not starting and loss of power. I would install points and see if this corrects the problem but I do not have any and they will not be here for a week (oh how I miss those days of get your parts the same day). If it runs good then the problem is the Pertronix system if not then maybe the coil (I think mines is a 3 ohm?), or the carb. Will check all cables and connections maybe tomorrow after work (if I have no honey do's). The carb leaking problem went away when installed the new fuel pump (good stream of fuel).

Thanks again for help!

Raul  

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waynep71222
User
Posts: 58
Joined: 04/12
Posted: 09/17/12 06:59 PM

first with pertronix...  look at the wiring connections to the coil terminals..

there is a red and a black from the pertronix unit... go to ring terminals on the coil studs...
a question..

but take a close look at where the positive wire is connected to the coil.. did the installer go to the extra 3 minutes and chop the right angle push on terminal off the positive wire... and crimp on a new ring terminal...  i have found several that had the ring terminal for the ignitor just slipped on and then the 90 degree push on elbow just holding the ring terminal tight.. this is not enough...   it requires the threaded on nut to pinch two ring terminals together to pass enough current..


pertronix really don't like to turn the power transistor on to ground the coil negative terminal when the positive voltage is too low...  no operation.. no spark.. sorry...

do you have a hand held digital volt meter????


now.. look at the starter solenoid on the inner fender...  unplug the I terminal...

hook up your volt meter that is now set to 20 volts scale to the i stud of the starter relay...
have a friend bump the starter... does the voltage on the i terminal jump from ZERO to around 11 volts while the starter is spinning..  this proves the solenoid is sending the proper by pass voltage...

move your test wire over to the wire you removed from the i terminal...   then unplug the S terminal connector...   have your friend at the ignition key slowly rotate the ignition key from the OFF position to the ON position to the cranking position.. then back to the on position then off..

you should have voltage.. but probably around 11.9 volts on that wire until the helper gets to the cranking position..  then the power should come back when he releases from the crank position...

this proves the ignition switch is working..

you can hook the S and the i wire up to the starter solenoid again.. do the same test touching the I terminal at the starter relay...

as the key turns on.. the power should come up to around 11.9... as the engine starts to crank.. you should get more... as the key is released.. it should drop back to 11.9 or so... without dropping to ZERO..

this is usually better done with a circuit tester..
off..
key on.. dim bulb..
cranking.. bright bulb.
after cranking key on.. dim bulb..
off..
there really should not be any drop outs during this test..


you could have a bad ignition switch

you could have a bad starter solenoid..

you could have a bad ignition switch connector..


this is the later dash mounted ignition switch...

LS302 Ignitionswitchforford

a lot of people have had the wiring terminals burn and go intermittent  

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Raulh
New User
Posts: 37
Joined: 09/09
Posted: 11/01/12 11:47 AM

Hi it has been a while since I last replied, work has been very busy. Well this what have done and the results. I put points, rotor and a new dist in (took out the electronic) and the car started and ran better but still was not running right. I timed it to specs (12 BTDC) and still was not right, so I advanced the timing and it ran better and spend so money and bought a new carb (Autolite 1100) and the girl ran a lot better; during this process I also found out I had a cylinder head gasket problem (antifreeze drips out where the cylinder and the block join together and seals when the engine gets warm).  A friend of a friend said that’s normal for an old car like mines (I do not think so). Now it is cold here and how I hate the cold!  Well the girl is going in the other garage to sleep but while she is sleeping I will take the cylinder head out and have it re-surfaced and have my mechanic replace what is needed.
The END.  Now for another question, the carb I bought is with out a Spark Control Valve and I have read that if you have a Loadomatic dist that one is required?
I have my doubts that it is required because in 1966 these were not out yet or were they?

Thanks all for the Help

Raul  

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waynep71222
User
Posts: 58
Joined: 04/12
Posted: 11/01/12 03:52 PM

first...   there are FREEZE plugs in the side of the head behind the exhaust manifold as i recall.. could those be leaking???  there is probably one at the back of the head also...


please do a compression test.. before taking the HEAD off...

early heads have SOFT valve seats...  there is another way...

ford made 200 motors as i am guessing thats what you have up through 79 or 80..  the 70 up engines used a larger carb mounting adaptor..  there is a company who sells to engine builders.. has this neat adaptor   its a part number CA200 from engine quest..

58628Eqlojpg 00000021693

this allows you to use the later heads that already have hardened seats on 69 and earlier models..  this would allow you to buy a reman or some way source a later head and make it a bolt on..

before you unbolt the head.. you might also want to check the lift of the cam.. on all the different cylinders.. to make sure you DON'T have a flat cam..  one where a cam lobe has failed.. worn round instead of egg shaped.. failing to open the valves all the way..    if you started the engine .. with the valve cover off.. you could see the push rods twist then stop.. or twist twist twist. in short pulses...  always the same way on each one...

if it spins franticly..  or rocks back and forth.. you could have a cam going bad..  as the lobe is worn down.. the lifter instead of spinning slowly.. either spins at high speed..  or spins back and forth..


while collecting parts .. pick up a tube of permatex Hylomar..  once you are ready to install the head gasket.. spread a THIN layer on both sides of the head gasket.. let it hang for 15 to 30 minutes for the solvents to evaporate..   i hate head gasket leaks and since i have been using this stuff.. i have not had one leak on me..

don't throw out your electronic ignition.. its far better than points if its set up properly.. there are issues with enough voltage to supply it on points type cars. but its not hard to fix that issue.

2

you can kinda see the hidden locations in the image below

5  

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pepsi1
New User
Posts: 36
Joined: 03/12
Posted: 11/04/12 07:22 PM

Raul:
Get a new friend...LOL... If the engine is sealed correctly it should not leak coolant. Now thats not true for the BBF the FE blocks they tend to leak coolant at the front. It's only because the intake manifold is 1/2 the cylinder head. NO CHIT.

  Have the head gone through. Let the machinist do a valve job and resurface the head. the engine should idle better also. Also if you want to. While the head is off the engine block.
  You can remove some of the carbon build-up on the tops of the pistons. Use a sraper and being careful not to nick the pistons if you do snad them down you want a smooth top. If you have a shop vac suck the carbon up with that. Take your time and you can do it....

Just a little FYI when my wife and I were going out she had a 66 Mustang with the bigger 6 cylinder in it. Brand new with 2,000 miles maybe. It idled like crap.The  Ford dealer said it was normal.(He was right thats the way they idled). I removed the head and had it resurfaced and relapped all the valves, put it back together.The engine was so smooth. The dealer wanted to know what was done to it to make it idle and run so smooth. It was very simple!!! Grin  Cool

Bob  

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