Thread: The problem: overheating at idle in drive – stalling when hot.

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The problem: overheating at idle in drive – stalling when hot.

The car: 1962 FORD “M” Series THUNDERBIRD 390 with TRI POWER. We have restored this TBIRd to be completely orginal.

This may not be classified as a true HOTROD, but I'm going crazy over this problem and have read the post on this forum. You have a lot of very knowledgably people.

Engine professional rebuilt approx 8 years ago by the former owner, but has only 3k miles on it. I'm not sure what it was bored out to.

I’m not sure if the carburetor is boiling over or I’m getting a vapor lock. When running on the road the temperature is reading normal, but in traffic or just sitting idling in drive the temp will go up, but not boil over, then the engine will start to surge, then stall. Immediately after it stalls, if I pumped the linkage, I get a good stream of gas down the carbs from the accelerator pumps. It must sit for 5 or 6 min after it stalls before it will start. We tried starting, after stall, with gas pedal to the floor the engine will turn over (at the correct speed) but will not fire up. We also tried without touching the gas, same results.

The engine runs perfect on the open road. The engine temperature stays normal as long as the car is moving. When floored, the secondary carbs will kick in, with no hesitation. When idling at normal operating temperature I getting about 17hg of steady vacuum.



What has been done – checked.

The 3 x 2 setup including the was rebuilt about a year and one half ago. I have the correct Bakelite (phenolic) carb spacers and gaskets. Tested for vacuum leaks – not leaks.

Idle speed in drive is approx 625 RPMs.

Float levels checked – just below sight screw. Checked with engine stopped after warming up. Took float level site screw out, slightly bumped car with my hip, had a little gas come out of bottom of screw hole.

Fuel pressure 5 psi at start runs up to 7-8 psi and steady when at operating temperature (slight fluctuation when engine starts to stumble before dying). Shop manual says 4 – 6 PSI, could 7+ be too high?

Checked for vacuum leaks.

Centrifugal and vacuum advance working correctly.

Timed by vacuum gauge (highest vacuum then back of 1 hg.

Completely flushed the engine and heater (no rust or dirt).

New (not rebuilt) water pump.

New recorded, 4-core radiator.

New 180-degree NAPA SUPERSTAT thermostat. With 1/8” holes drilled at 12 and 6 o’clock.

Full fan shroud.

All new hoses.

Added RED LINES WATER WETTER to 40% antifreeze / 60% water.

Checked to make sure fan was on correctly.
To test if it need more air movement, we installed a 7 blade fan with clutch, no change, went back to the fixed 5 blade.
Checked the size of the water pump pulley.
Checked for any lose fuel line connections from carb to the tank.

Rerouted the metal fuel line away form major heat sources. We even bypassed the metal line with a rubber fuel line from the pump to the fuel rail to eliminate the metal line as a source of the problem.

Insulating washer (spacers) installed between the fuel rail mounting tabs and the manifold. The fuel rail was mounted directly to the intake manifold by two manifold bolts.

We have been told the head gaskets might be on backwords, blocking the correct front to back flow of collent. Is there any way to check this without pulling the heads?

Any suggestion will be appreciated.

Thanks
Orlando Amato
62 M Series Convertible

VTCI #10064

Some pics of our TBIRD
http://new.photos.yahoo.com/tst7626/...60762344376692

Wow. Quite a list of things done and checked!! The head gaskets are easy to spot if backwards. If installed correctly you should see a square shape sticking out of the front on both sides. I also see more guys having these problems even with GOOD replacement parts. I've heard pros and cons about aluminum vs brass rads. Also that recored rads don't cool as well. I don't know. My Cougar has a 390 and the stock rad still and runs really cool at idle and in traffic so far. Are you using a surge/puke tank? BTW sounds like a REAL nice car and to me it's a HotRod!!

Oh BTW what is the size of the WP pulley on there now?

Originally Posted by tst7626

The problem: overheating at idle in drive – stalling when hot.

The car: 1962 FORD “M” Series THUNDERBIRD 390 with TRI POWER. We have restored this TBIRd to be completely orginal.

This may not be classified as a true HOTROD, but I'm going crazy over this problem and have read the post on this forum. You have a lot of very knowledgably people.

Engine professional rebuilt approx 8 years ago by the former owner, but has only 3k miles on it. I'm not sure what it was bored out to.

I’m not sure if the carburetor is boiling over or I’m getting a vapor lock. When running on the road the temperature is reading normal, but in traffic or just sitting idling in drive the temp will go up, but not boil over, then the engine will start to surge, then stall. Immediately after it stalls, if I pumped the linkage, I get a good stream of gas down the carbs from the accelerator pumps. It must sit for 5 or 6 min after it stalls before it will start. We tried starting, after stall, with gas pedal to the floor the engine will turn over (at the correct speed) but will not fire up. We also tried without touching the gas, same results.

The engine runs perfect on the open road. The engine temperature stays normal as long as the car is moving. When floored, the secondary carbs will kick in, with no hesitation. When idling at normal operating temperature I getting about 17hg of steady vacuum.



What has been done – checked.

The 3 x 2 setup including the was rebuilt about a year and one half ago. I have the correct Bakelite (phenolic) carb spacers and gaskets. Tested for vacuum leaks – not leaks.

Idle speed in drive is approx 625 RPMs.

Float levels checked – just below sight screw. Checked with engine stopped after warming up. Took float level site screw out, slightly bumped car with my hip, had a little gas come out of bottom of screw hole.

Fuel pressure 5 psi at start runs up to 7-8 psi and steady when at operating temperature (slight fluctuation when engine starts to stumble before dying). Shop manual says 4 – 6 PSI, could 7+ be too high?

Checked for vacuum leaks.

Centrifugal and vacuum advance working correctly.

Timed by vacuum gauge (highest vacuum then back of 1 hg.

Completely flushed the engine and heater (no rust or dirt).

New (not rebuilt) water pump.

New recorded, 4-core radiator.

New 180-degree NAPA SUPERSTAT thermostat. With 1/8” holes drilled at 12 and 6 o’clock.

Full fan shroud.

All new hoses.

Added RED LINES WATER WETTER to 40% antifreeze / 60% water.

Checked to make sure fan was on correctly.
To test if it need more air movement, we installed a 7 blade fan with clutch, no change, went back to the fixed 5 blade.
Checked the size of the water pump pulley.
Checked for any lose fuel line connections from carb to the tank.

Rerouted the metal fuel line away form major heat sources. We even bypassed the metal line with a rubber fuel line from the pump to the fuel rail to eliminate the metal line as a source of the problem.

Insulating washer (spacers) installed between the fuel rail mounting tabs and the manifold. The fuel rail was mounted directly to the intake manifold by two manifold bolts.

We have been told the head gaskets might be on backwords, blocking the correct front to back flow of collent. Is there any way to check this without pulling the heads?

Any suggestion will be appreciated.

Thanks
Orlando Amato
62 M Series Convertible

VTCI #10064

Some pics of our TBIRD
http://new.photos.yahoo.com/tst7626/...60762344376692

7 PSI is to much.
At this presure it may try and push it by the needle and seat assemble and if it does then it will become way rich.
I would try and keep it in the 5-6 lbs. area at the seat.
1.What temp does it hit at idle?
2.What is your intial timing at ?
3.What is your total timing at?
4.Have you tried a "vented" gas cap?

My first guess would be too little timing (retarded). Also idle speed seems a bit slow...

Erik raises good questions above

-Chris

Wow, what fast responses!!

Let me go through the posts.

Looked all around the head gaskets, cannot find any tabs or anything sticking out. Anyway to tell if I have the rocker arms off and look down into the engine?

I do not have any overflow. The coolant level always is correct, just at the level indicator plate in the expansion tank.

I checked out another 62 TBIRD, that someone had put a 3 x 2 carb setup on with a EMPI dial type fuel pressure regulator. The older gentlemen who owned the Tbird told me the car ran like sh—without the regulator.

The temp gauge on the TBIRD does not use numbers, just markings. I have an IR thermometer and at the upper hose it hits about 190 degrees. I know these are very inaccurate, But I don’t think it is really getting too hot because I never have it overflow (even when I tried a 7lb radiator cap). I have a new 14lb cap on now.

Initial timing with vacuum advance line disconnected is set at 9 degrees, It is hard to tell what I’m getting for centrifugal advance and vacuum advance without a timing wheel installed, but I do see it jump up when I raise the idle to about 800 – 900 rpms. By the way the vacuum advance is connected tot the center carb and has no vacuum at idle.

The car has a vented gas cap. I tried removing the cap (while idling in the driveway) still got a little hot, started to rough, surge then stall.

I have fooled around with the timing advanced, right on the timing mark and retarded, same results.


I really appreciate all this help. This is driving me crazy!! My wife says it is a short drive….

Lots of information right up front.
Well done there.

I'm with Eric on the fuel pressure, try a regulator.
Holley makes a nice one that's not too costly.

Time the engine with a timing light.
You'll probably find the timing off a bit.
The timing light will also tell you if the mechanical and vacuum advance are working.
Retarded timing at idle is a big cause of overheating.

One small hint about the two 1/8" holes drilled in the thermostat flange - one is sufficient for an air lock relief.
Two will bypass too much coolant for a reasonably quick warmup.

In 16 degree F weather my 32 roadster with 462" Buick engine running two 1/8" holes in the 180 themostat takes 4-5 miles of 35-40 mph cruising to hit warm on the water temp gauge and you can tell the oil is not sufficiently warm at that time.
Running another of the same brand 180 degree thermostats with only one 1/8" hole drilled, the water temp hit's 180 in one mile on the same road - also during 16 degree weather - and the engine oil temp is warmer at the end of the 4-5 miles . . . to the donut shop.


Your overheating is very much like the Ford 400-M (Cleveland tall deck block) engine in my 77 Ford 3/4 ton 4x4 did.
Ran a few degrees warm on the highway in summer, but well within limits.
About 190 degrees vs 180 with a 180 degree Chevy thermostat.

It overheated in traffic to the point where you'd be looking for an escape route after 5-10 minutes - depending on the ambient temp.

Problem was:
At the time Ford and the other thermostat manufacturers made only one thermostat for the 400-M engine.
197 degrees rated.
I wanted a 180 degree thermostat and found a Chevy pattern thermostat dropped right in.

I didn't realize at the time that Ford stats have a plug on the bottom of the stat that closes off the bypass hole in the bottom of the thermostat well when the stat is open.
That allowed a little less than half the coolant to circulate in the block instead of having all the coolant go through the radiator.

The problem can be cured by either installing the correct pattern Ford thermostat or . . . tap the hole at the bottom of the thermostat well and install a flush head allen driven pipe plug.
1/4-NPT if I remember right.
That allows a Chevy pattern stat to be installed and all coolant then goes through the radiator.
Warmup does take longer, but at the time I lived in SoCal so no big deal.

Take a look at your FE engine's thermostat well and see if there's a 3/8" or so hole at the bottom of it.

Only took me one re-cored with a Desert core radiator, one water pump, trips to two radiator shops that couldn't figure it out along with a few worrisome miles before I realized what I'd done.

Sometimes we shoot ourselves in the foot and don't even know it....

Initial timing with vacuum advance line disconnected is set at 9 degrees, It is hard to tell what I’m getting for centrifugal advance and vacuum advance without a timing wheel installed, but I do see it jump up when I raise the idle to about 800 – 900 rpms. By the way the vacuum advance is connected tot the center carb and has no vacuum at idle.

You may want to try connecting the distributor's vacuum advance line to full-time vacum.
If everything else is as it should be that usually cures GM engines from overheating at idle.

You'll have to back off the idle speed screw, the added advance will make the engine speed up a little bit.

Reason it works is, the fuel/air ratio is lean at idle speeds and the added time allows for a better burn.

It isn't the gaskets in backwards. You won't get out of sight of home if that's the problem.
I had a 390 that acted much the same as yours. My problem was the lifters would collapse at idle for any length of time. Aftermarket crappy lifters. Put new Ford lifters in, ran perfect.
I wish I had your problem, as long as the 'Bird went with it!!!

You had mentioned that you checked the fan for air flow. Is the fan far enough into the shroud? The fan should be deep inside the shroud but no closer than one inch of the radiator to work properly. If its not it won't pull enough air at idle to cool the engine. If your using a fan clutch, when the engine is at operating temperature it should lock up and pull air through the rad. I would also recommend switching to a 160 thermostat to help out. Its not necessary to run a 180 stat in the old cars and, don't drill any holes in it, the factory never did nor should you! I would also check coolant flow through the radiator when its warm. Start the car when cold with the rad cap off and allow it to warm up. You will push some coolant out as it warms up but thats ok, just keep an extra gallon there to top it off when hot. Once the thermostat opens up and the engine is full warm you should see coolant stream out of the rad core into the side tank. This should be a nice strong stream, if it isn't you may have a partial blockage in the radiator or the water pump flow may be insufficient. Once warm the coolant should reach a constant level. If it keeps pushing out or has any air bubbles in it then look into the possiblity of your head gaskets being on backwards. I think that your no start and stalling when hot is a direct result of vapor lock from the overheating. Fix the overheating and it should be fine. Good luck!

Does the car have a good fitting radiator shroud on it??? The first step in isolating the problem might be to install a mechanical temperature gauge and get some real numbers as to what the engine is running. Those old Birds are tight quarters under the hood, in traffic or idling they will build up some high under hood temperatures.... I had a 66 Fairlane with an FE years back with similar stalling problems in traffic. The problem was fuel. I used the second port on the regulator as a return line with a bypass pill in it as used in mechanical fuel injection. My pressure at the carb was 5 PSI. If the problem is fuel related and not heat related, there are a number of companies making fuel pressure regulators with a regulated return port now.

The problem continues!

I installed a Holley fuel pressure regulator last night. Started the engine and adjusted it down to 5 lbs. Car ran at idle for 15+ min before it started to run rough and then die. I sounded like it was not hitting on all cylinders. If I revved it up, I could still hear it missing.

I’m going to change out the Pertronix 1 (old style) ignition and the Pertronix high voltage coil back to the original points and original coil. Could a coil shorting out or the Pertronix ignition going wacky when it gets to a specific temp cause this kind of problem.

It was raining last night and I did not take the car out of the garage. It was about 90 degrees in the garage as I was testing. The TEMP never really when ALL THE WAY UP, (It just has tick marks no numbers) it stayed just to the high side of the midway marker. On the highway it stays just to the high side of the ¼ marker.

I’m still not sure if the head gasket is on backwards. How long would it take to get all the way to the H (I know how stupid it sounds without having an actual temp gauge) if the gaskets where on wrong? I thought there is a head alignment dowel pin that would make installing the gaskets backwards very difficult. As a last resort I will pull the heads. A real pain on this show car.

Also I posted some pictures on the photo gallery.

ANY OTHER SUUGESTIONS????

Thanks again for all the help and responses.

If it can idle for even a few minutes without boiling over, I doubt it's the gaskets in backwards. They have a big opening in one end, if that opening is at the front all the water flows through the front of the engine and the back cylinders overheat very quickly.
You said it was rebuilt 8 years ago. Did it sit for years without any coolant in it? The metal blockoffs might have corroded through, allowing a little water to circulate through the front holes and causing a slower heating condition.

Originally Posted by blueoval67

Its not necessary to run a 180 stat in the old cars and, don't drill any holes in it, the factory never did nor should you!

I've found the 180 stats to work well in weather from 16 degrees F to 109 degrees F.

As far as drilling a single hole in the stat goes, it's a small modification that makes life easy as far as potential air locks go and creates no other problems.

Not many cars would be modified if we stuck to stuff that only factory engineers did.
If we did, we'd be restorers and not hot rodders....

It was full of coolant. I checked it when I got home about a 50 / 50 antifreeze - water mix. When I drained the rad and the block, I strained the fluids and there was very little sediment. Also had 8 qrts of oil in the crankcase. The older gentleman I purchased the car from, would pull the plugs and shoot some oil down the cyl every few months and turn it over a few times. He had the engine rebuilt and wanted to keep it in good shape.