239 Y-Block Trouble F250

[Chris_AAFord]

I went to my local starter and alternator shop and was able to get a new starter. The starter does seem to have a little more speed than the old starter. But i'm still having the same issue.

The Truck sat for two days, I bolted the new starter up and the truck fired up instantly. I let it warm up and drove it around the block and then it would not restart.(cranks but does not start).

Is it safe to assume that I can eliminate a poor ground issue at this point? It's not the starter.

The truck has a pretty thick gas smell so I'm starting to lean in the direction of Flooding. My second thought is maybe the timing is off but it runs pretty good when it starts. Is it possible for the timing advance to be stuck in the advanced position and then settle back into the retarded position once the engine cools down? This is the load-a-matic distributor.

Thanks for all Help.

Chris

[KULTULZ]

Originally Posted by Chris_AAFord

The truck has a pretty think gas smell so I'm starting to lean in the direction of Flooding. My second thought is maybe the timing is off but it runs pretty good when it starts. Is it possible for the timing advance to be stuck in the advanced position and then settle back into the retarded position once the engine cools down? This is the load-a-matic distributor.

What is the state of tune of the engine? You have checked the points and basic timing, plugs and wires, operation of the LOM dist, compression test?

After a 2nd hard crank have you pulled a plug to see if it is wet? Depending on how the engine was previously treated and used, the fuel may be bad.

I would throw a carb kit in it and verify good fuel filter, fuel pressure, fuel lines integrity and bring the IGN to specs before beating my head against the wall.

You maybe should also do a starting system voltage drop test when the engine is cold and then hot. This will give you an indication of any problem(s) in the starting circuit.

[KULTULZ]

Originally Posted by Chris_AAFord

I went to my local starter and alternator shop and was able to get a new starter. The starter does seem to have a little more speed than the old starter. But i'm still having the same issue.

The Truck sat for two days, I bolted the new starter up and the truck fired up instantly. I let it warm up and drove it around the block and then it would not restart.(cranks but does not start).

The truck has a pretty thick gas smell so I'm starting to lean in the direction of Flooding.

Sounds like carb/fuel line heat soak and percolation. Does fine when cold but when hot after shutdown, the fuel in the fuel line expands and forces the needle/seat to open, flooding the carb and engine.


Don't count out fuel blend separation also.


Tee in a fuel pressure gauge and watch it after shutdown. Keep hood closed.

[Chris_AAFord]

Thank you!

What do you think of this test I just thought of. I’m going to start the truck and get it good and hot, crimp the rubber fuel line and let it burn off all the gas in the carb until it dies.

Then I’ll un-crimp the line and see if it starts. If it starts this should indicate that too much gas / flooding is the reason for the no restart condition.

Thanks again for your help.

Chris

[scicala]

Vapor lock does not cause the carb to overfill and flood the engine. Basicly the opposite of that. The vehicle runs out of fuel because the fuel pump cannot push the vapor in the fuel line or fuel pump, so the carb goes dry.


Sal

[KULTULZ]

Sponsored Links (Register now to hide all advertisements)

Originally Posted by Chris_AAFord

What do you think of this test I just thought of. I’m going to start the truck and get it good and hot, crimp the rubber fuel line and let it burn off all the gas in the carb until it dies.

Then I’ll un-crimp the line and see if it starts. If it starts this should indicate that too much gas / flooding is the reason for the no restart condition.

Thanks again for your help.

Chris

That will work (remember, the carb will be completely dry and may take a while to function correctly) but it would be easier (IMO) before attempting to start a hot engine would be to look down the carb body to see if the throttle plates are wet and/or fuel is dribbling from the throttle bore shaft and/or mounting gasket.

Your particular problem is hard hot start, no problem running after cold or hot start?

Once the plugs become wet/carboned, the cylinders have to somewhat dry out before she will fire. Sounds like fuel percolation and needing the carb rebuilt to correct specs.

It is not the engine so much (though it does need servicing) as today's gasoline. It is formulated for EFI and EVAP.

Vacuum and Fuel Pump - Star Products TU-1PB

[dmsfrr]

.
If the fuel line isn't very new crimping it may split it on the inside while looking ok on the outside. Then make a big mess a few days later when you aren't looking.

Originally Posted by Chris_AAFord

. . . Is it possible for the timing advance to be stuck in the advanced position and then settle back into the retarded position once the engine cools down? This is the load-a-matic distributor.

Yes it can be stuck, but not usually in the advanced position. You can check it with a timing light.
Look for a timing change from idle to partially open throttle.The moving plate the points are mounted to may need to be cleaned and lightly lubed after all these years.
While you're in there it won't hurt to double check the ground connections for the points.

[Chris_AAFord]

I didn’t get to read the last two post before I started working on the truck this evening but I think I was heading in the same direction.

Again, the truck fired cold on the first turn and yes it runs pretty good once it’s running from what I’ve seen taking it around the block. I drove the truck around the block and got it good and hot. Again, once I shut it off I could not get it restarted. One thing I noted was that the manifolds were very hot but the fuel lines were not hot at all.

Next I found a old fuel pressure gauge in the garage and hooked it up post fuel pump, my first surprise was that the truck all of the sudden was running again with the fuel line off the carb. The fuel pressure gauge read a little over 5 PSI. I ran out to the parts store and got a simple inline fuel pressure regulator set it to 2 psi and it fired up and it seemed to run smoother at idle. I let it run for awhile and tried to restart it, it didn’t start right away but I was able to get it Started after some cranking.

I set the regulator to 2 psi but when I gave it gas it started to stumble so iturned it up to 2.5 PSI which helped. I lowered my float level quite a bit so I probably need to raise that back up now that I have the correct fuel PSI. I’ll work on that tomorrow.

Why is my factory fuel pump putting out too much pressure? How were these regulated from the factory?

-Chris

[dmsfrr]

Were the exhaust manifolds abnormally hot?
I'm not meaning to go overboard about timing since it likely isn't causing the hard starting problem but your 'stuck timing advance' and "very hot" comments reminded me... here's a link to an article about timing advance. It was written for '55/'56 T-bird owners but applies to any load-o-matic distributor.

https://www.ctci.org/gilsgarage/Crac...stManifold.php

[Chris_AAFord]

Originally Posted by dmsfrr

Were the exhaust manifolds abnormally hot?
I'm not meaning to go overboard about timing since it likely isn't causing the hard starting problem but your 'stuck timing advance' and "very hot" comments reminded me... here's a link to an article about timing advance. It was written for '55/'56 T-bird owners but applies to any load-o-matic distributor.

https://www.ctci.org/gilsgarage/Crac...stManifold.php

The manifolds did not seem to be excessively hot, I was just trying to make the point that the engine was at operating temperature and the fuel lines did not seem to be holding much heat.

I’ll take a look at that loadamatic article. Thank you.

[KULTULZ]

Originally Posted by KULTULZ

Don't count out fuel blend separation also.

Originally Posted by scicala

Vapor lock does not cause the carb to overfill and flood the engine. Basicly the opposite of that. The vehicle runs out of fuel because the fuel pump cannot push the vapor in the fuel line or fuel pump, so the carb goes dry.

Sal

Sal,

Vapor lock (experienced on suction side of mechanical fuel pump) was not referred to, blend separation was, although either could be a contributing factor depending on fuel type and/or condition.

If the vehicle experiences excessive heat soak, either malady can contribute to no-start on an attempted hot start.

Am I somewhat correct in my assumption(s)?

[Motorhead6]

Originally Posted by paul2748

It sounds like you need the starter rebuilt

Pail hit on a very common problem with those old carbs. Symptoms are exactly as you are experiencing. A rebuild is in your future or better yet, a new reproduction carb is available from many sources. Those old carbs are near impossible to make and KEEP right; always leaking. There are people reading this that will offer a rebuild and will do a very good job.
Save money in the long run with a new carb. Also, the fact that it is leaking externally probably means the butterfly shaft bores are worn. Replace with a new carb; you will be happy you did.

My opinion and worth every cent you paid for it.

[rotorwrench]

Actually is was the shade tree wrenchers that did the damages to some carbs more often than not. They aren't a bad design. Power valves can blow out and leak and castings can get warped by heavy handed assemblers. Any substantial leak in the induction system will flood a warmed up engine after shut down. If the spark plugs get wet fowled during start attempts, they take a while to dry back out. Some of the late type power valves don't seal up right either.

When there is heat sensitivity involved, the first and cheapest thing you can do is replace the condenser in the distributor. If the points are burned by a bad condenser than they should also be replaced. I use the Echlin brand stuff from NAPA but they were recently bought out by Standard Motor Parts so I hope they keep up the quality standards of the Echlin company. I always keep a new spare condenser around just in case one doesn't live up to its potential. They just aren't as reliable as they used to be back in the day.

[scicala]

Too many people and suggestions gets confusing to the original poster sometimes. Have fun.


Sal

[Chris_AAFord]

Any thoughts on the 1/4 inch thick gasket between my carb and intake? Is this necessary or can I use the standard gasket that came with a rebuild kit?

[50fordcoupeman]

Not a wives tale. Coils can fail when they get hot. Mine started/ran perfectly until the coil would get hot. This took 7 or 8 miles. I had 4 new "quality" coils from NAPA that failed. Junk from wherever..........

[CrownVic55]

That was my point on post #2. Changing out the coil is a lot easier and cheaper than some of the things he has tried. Years ago on my 55 it had the same problems. Maybe with two people suggesting it, he will try a new coil.

[KULTULZ]

Originally Posted by KULTULZ

Sounds like carb/fuel line heat soak and percolation. Does fine when cold but when hot after shutdown, the fuel in the fuel line expands and forces the needle/seat to open, flooding the carb and engine.

Don't count out fuel blend separation also.

Tee in a fuel pressure gauge and watch it after shutdown. Keep hood closed.

The first two and a half minutes of this video will show heat percolation effect on fuel line delivery/pressure (on pressure side of mechanical fuel pump)-

https://www.youtube.com/watch?v=cadNfSNi_Oc

The below was found regarding the 57 BIRD 312 SC engine. It (fuel percolation - vapor lock) was also a problem then with good fuel (then blended for carburetion).

Post from another board-

'55-'57 'Birds have a long standing issue with under-hood operating temperature. One of the things I learned at Ford Carlisle last year (the E & F code reunion) was the change Ford made with the Phase II superchargers used on the 'Birds.


Only on the 'Birds, Ford added a fuel return line from the engine compartment to the gas tank. The return line provides a constant flow of fuel from the engine compartment back to the gas tank to serve as a way to keep the under hood fuel temp down to prevent vapor lock.

[Chris_AAFord]

I did put a new coil on, it did not fix the issue. I also put a new carb on, it runs a lot better but same issue.

Great video on vapor lock- I did not know the gas could boil so low. Any tips to fix this if your not interested in adding an electric fuel pump?

When I have my warm no start issue, the car will not react to starter fluid. If my issue was vapor lock, shouldn’t I get some popping with starter fluid?

Thanks,
Chris

[KULTULZ]

Chris-


The first thing you do when a car stops and/or won't start is to check for IGN spark and FUEL delivery.


Saves a lot of time and money by simply replacing this and that and hoping.


The video showed the problem(s) that can result with modern low boiling point fuel. It was even a problem when the vehicle was new (and used fuel for the period).



Ascertain what problem(s) you actually have and we can go from there.