Gets hot and stalls out

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itsfishy

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I have a 67 Barracuda with a 408 and iron heads, which means it likes to get hot. This past weekend I took the car out for a quick spin to test a new alternator (Powermaster 95 amp). I pulled into a parking lot and hit stop-and-go traffic; the car got to 210 but held there (weather: 85 degrees and overcast). I shut it down for about 5 - 7 minutes while I ran a quick errand. When I got back and hit the key, it was over 210 but that was to be expected. I started it and pulled out of my space...and it stalled. Tried starting it several times and it would catch and then immediately die again the first couple of times, and then after that it wouldn't catch at all but you could smell the fuel. Ended up having to push it back down the parking lot aisle to get out of the way. It's not unusual for it to take a minute to start after it's been sitting and the temp climbs, but this is the first time it stalled out on me. After about two hours it started up again - and of course had cooled down significantly. It has an MSD 6AL and Blaster 2 coil, MSD plug wires, Holley 750 cfm carb. It does have a hood liner that I've been thinking about removing to try and get the engine bay temps down. It could just be a fluke this time but I'd prefer to not have to push it again if I can help it, so looking for any "preventative medicine" and/or suggestions as to why it happened this time. Many thanks!
 
Bring some alligator clip extension leads.

Next time it happens try jumping around the ballast resister.

If that does not work try batt positive to the coil side of the ballast resister, or coil positive itself.

Basically what you will be doing is rulling out a bad ballast

And a bad ignition switch.
 
Sounds like fuel percolation to me. 210 isn't hot but enough to cause fuel evaporation issues. Edelbrock carb?
 
Dana67Dart said:
Bring some alligator clip extension leads.

Next time it happens try jumping around the ballast resister.

If that does not work try batt positive to the coil side of the ballast resister, or coil positive itself.

Basically what you will be doing is rulling out a bad ballast

And a bad ignition switch.
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Will do. I don't get any backfiring, and it's starting fine when it's cool which is why I figured a heat-related issue, but know enough to know that this could be like chasing an electrical issue.
 
I had a pinto do similar. Every once in a while the engine would just die. Wait 20 minutes, start right up and run fine for an undetermined amount of time.

The ECU had a known heat issue.
 
I run mine at from 205>207 by IR gun, on purpose, with a Carter engine-mounted, HO mechanical pump; and a one piece fuel-line from pump to carb, the filter being at the back. It has no percolation issues.
I did have hot-running issues in the beginning, which I traced to too-tight Ring-gaps. The .0065 per inch rule did not work in my 367, with KB107s. I opened them up to .0080 and Badaboom, problem solved.
 
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AJ/FormS said:
I run mine at from 205>207 by IR gun, on purpose, with a Carter engine-mounted, HO mechanical pump; and a one piece fuel-line from pump to carb, the filter being at the back.
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The pump is engine mounted; I honestly would have to go look to see what it is because I don't remember. The filter is between pump and carb, and this weekend I'm going to replace it just to make sure I've got a fresh one on. I've got a few things to get done on it (new front shocks, oil change, air/fuel filter change) before the end of the month.
 
OldmanRick said:
Coil itself could be the issue...
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Thought about that. That coil is pretty old, but it doesn't have a lot of time on it. But I thought that if the engine bay is getting really hot it could cause an expansion in the coil. I don't mind throwing $75 at it for a new one but figured I'd get some input from the forum first.
 
Try and borrow one or get a cheap stock replacement to test before buying a good one.....if you really think that could be the problem.

P.S. Just saw the pic in your welcome thread. Absolutely beautiful car...:thumbsup:
 
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OldmanRick said:
Try and borrow one or get a cheap stock replacement to test before buying a good one.....if you really think that could be the problem.

P.S. Just saw the pic in your welcome thread. Absolutely beautiful car...:thumbsup:
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Good thought - thank you. And thank you!
 
Your engine should never see over 180 on the gauge.

Do some work to the cooling system and get your temperature down. It will make more power.
 
Your fuel is boiling due to the lower boiling temp of the ethanol. If your using a manual fuel pump. You need to put a return filter between the pump and the carburetor as in the first picture. If your using an electric pump install a regulator in the return after the carb as in second picture

I had the same problem on several cars. It will start and then flood. The floats won't shut the needle and seat because the fuel is boiling and dead ended up against the needle.

You will not believe the difference in the way the car runs if you do this.

100_0101 (2).JPG


Steve 107.JPG
 
Newbomb Turk said:
Your engine should never see over 180 on the gauge.

Do some work to the cooling system and get your temperature down. It will make more power.
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I’ve tried all kinds of things to get it down: currently has an aluminum radiator, custom shroud, gap on the water pump, pulled some blades from the pump. I’ve seen all kinds of other suggestions on the forum but haven’t tried any yet. If you have some simple-to-try suggestions to start with please tell me! One I saw that looked interesting was reducing the flow, which was almost counterintuitive to me. Please keep in mind that 110-112 degree days isn’t unusual in west Texas, so I’d be ecstatic to get the temp down!
 
Oldmanmopar said:
Your fuel is boiling due to the lower boiling temp of the ethanol. If your using a manual fuel pump. You need to put a return filter between the pump and the carburetor as in the first picture. If your using an electric pump install a regulator in the return after the carb as in second picture

I had the same problem on several cars. It will start and then flood. The floats won't shut the needle and seat because the fuel is boiling and dead ended up against the needle.

You will not believe the difference in the way the car runs if you do this.

View attachment 1716231146

View attachment 1716231148
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I have the same setup as you do in pic 1, EXCEPT my fuel line and filter are essentially against the block (more or less between the alternator bracket and block). Hopefully the pics attached show the setup. I was concerned that putting the line on the other side of the bracket could interfere with the alternator belt. Will moving that line give better cooling for the fuel?

IMG_4091.jpeg


IMG_4090.jpeg
 
Is that a return style filter? How many hose nipples does it have? You want to keep the fuel moving and not dead ending it at the carburetor under pressure.
 
itsfishy said:
I’ve tried all kinds of things to get it down: currently has an aluminum radiator, custom shroud, gap on the water pump, pulled some blades from the pump. I’ve seen all kinds of other suggestions on the forum but haven’t tried any yet. If you have some simple-to-try suggestions to start with please tell me! One I saw that looked interesting was reducing the flow, which was almost counterintuitive to me. Please keep in mind that 110-112 degree days isn’t unusual in west Texas, so I’d be ecstatic to get the temp down!
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I’m not sure why you went to less blades on the pump. I use Milodon high volume pumps and they have 8 impellers.

You should be using a mechanical fan.

The water pump should turn no less than crank speed. So 1:1 should be the slowest you run the pump. Over driven is best.

Don’t forget the fan turns the same speed as the pump. Slow down the pump, you slow down the fan. That’s the last thing you want.

At high ambient temps and low rpm situations you need as much coolant and air flow that you can get. Slowing down the pump is bad policy.
 
itsfishy said:
I’ve tried all kinds of things to get it down
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210 is not too hot for the engine, never has been never will be. Modern engines run there from the factory.

If you have a super duper wamo engine with tight clearances then maybe but a stock or stockish engine built to OEM or aftermarket part specs will have no problems.

16 lb cap, proper cooling SYSTEM, meaning pulleys, pump, fan, rad.


Is it a fuel problem, an electrical problem??

You will have to do a bunch of diagnostics to make that determination.

To rule out ethanol fuel being the problem find a fuel seller with alcohol free fuel, run your tank down to almost empty, and fill it up with alcohol free.

Then see if the problem comes back.

www.pure-gas.org


heat could be the ignition switch, the connector, the ballast, the coil, the ECU, the dist, and the wiring and any connectors between
 
Oldmanmopar said:
Is that a return style filter? How many hose nipples does it have? You want to keep the fuel moving and not dead ending it at the carburetor under pressure.
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Ah, I gotcha. Sorry, I’m still learning and the curve is steep. No it is not. And a return system will cut down on the chance of vapor lock, right?
 
You need to get an IR temp gun and hit the temp of the top tank where the upper hose goes in and then hit the bottom tank where the hose comes out and see how efficient that radiator is. Just because it's new and shiny doesn't mean it's good. A lot of times, the further away you get from stock, the worse these problems become. Remember, there were factory STOCK engines that put out way more power than what you have running totally STOCK cooling systems. You have something WRONG.
 
Newbomb Turk said:
I’m not sure why you went to less blades on the pump. I use Milodon high volume pumps and they have 8 impellers.

You should be using a mechanical fan.

The water pump should turn no less than crank speed. So 1:1 should be the slowest you run the pump. Over driven is best.

Don’t forget the fan turns the same speed as the pump. Slow down the pump, you slow down the fan. That’s the last thing you want.

At high ambient temps and low rpm situations you need as much coolant and air flow that you can get. Slowing down the pump is bad policy.
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Understood. I’ve got a mechanical fan on the car; maybe I need to look into a high volume pump. I know the modern cars run at 210 and are fine with it, but I’ve always thought that to be an apples-to-oranges comparison. Plus (to be honest) I’ve already melted down one motor so I’m hypersensitive to temps.
 
itsfishy said:
Understood. I’ve got a mechanical fan on the car; maybe I need to look into a high volume pump. I know the modern cars run at 210 and are fine with it, but I’ve always thought that to be an apples-to-oranges comparison. Plus (to be honest) I’ve already melted down one motor so I’m hypersensitive to temps.
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Unless you have a high flow thermostat, a high volume pump will not pump the volume it could, because the thermostat is not a high flow unit. I agree with Oldmanmopar on one hand. 210 isn't too hot. It is however "on the way" considering outside influences such as traffic jams, humidity and hot days. At 210, there's not enough of a "cushion" for circumstances outside the box, like those described earlier.

On the other hand I also agree with Newcomb Turk. (what a dorky name) lol A performance engine doesn't have to run hot. In fact, I took several of his recommendations when I was tuning my HP slant 6 and every single one of them helped and ultimately I solved the issue completely. Now the engine never sees close to 190 degrees. People argue that's too cool, but if the engine is TUNED for it, that's the secret. Any and everything you can do to keep the incoming air and fuel cool coming into the engine will help it run cooler and make more power, too.
 
RustyRatRod said:
Unless you have a high flow thermostat, a high volume pump will not pump the volume it could, because the thermostat is not a high flow unit. I agree with Oldmanmopar on one hand. 210 isn't too hot. It is however "on the way" considering outside influences such as traffic jams, humidity and hot days. At 210, there's not enough of a "cushion" for circumstances outside the box, like those described earlier.

On the other hand I also agree with Newcomb Turk. (what a dorky name) lol A performance engine doesn't have to run hot. In fact, I took several of his recommendations when I was tuning my HP slant 6 and every single one of them helped and ultimately I solved the issue completely. Now the engine never sees close to 190 degrees. People argue that's too cool, but if the engine is TUNED for it, that's the secret. Any and everything you can do to keep the incoming air and fuel cool coming into the engine will help it run cooler and make more power, too.
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It looks like I’ve got some sleuthing to do. Dana67Dart gave a whole list of stuff, but I think hitting the tank and seeing how efficient it is makes a ton of sense as a starting point. I’ll also check into a return system; that makes sense to me as well just because it seems like it will help with one of the possible causes (and possibly be a preventative measure too). I’ve got a lot to learn- thank you all for the expertise.
 
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