I have a new problem !
The Dart is dying as if it is vapor locking.
It has a 225 and 904 from another 64 GT and we've been driving it since late last year.
When we installed the motor and tranny we replaced the fuel pump,carb (1 bbl. Holley),coil,cap,rotor,plugs, belts and hoses.
It ran great driving from Arizona to North Carolina in December.
We just replaced the points for the first time since the motor was installed and my brother-in-law helped out with the proper gap (.020) and we checked the timing as well. It's set at 2.5 degrees and idles at 750 rpm.
The vaccum advance is connected and working properly.
The choke has been set and is working correctly also (thanks to the info from this forum!).
Now what it's doing is completely dying after driving it for a couple minutes. Yesterday when this happened it would crank but would not start up and run. We ended up towing it home and decided to let it sit for almost an hour and then it would start right up and run fine.
I explained the problem to my brother-in-law and he said it sounds like it's vapor locking.
The weather here now is hot and humid and seems to have an effect on this problem. A few days ago when it was raining we drove it around for at least an hour (just after the tune up) and it ran perfect.
It will run great until the motor is warmed up and then it dies.
I've heard about vapor locking before but never had it happen to me.
Is this whats happening ???
I've been told about a couple of remedies but haven't tried anything yet.
Any advice ???
Thanks, Lee

Have you done the fuel line mod? If not that might do ya.

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83 B-150 slant 6,4 speed. 79 B-300 360 pathfinder 4x4. 74 W-300 318 4x4 git-r-done 80 B-100 sl6,4speed

Yep, try the Fuel line mod. And tune-up parts and technique suggestions in this thread. Carburetor operation and repair manuals (and some training movies) are posted here for free download. And remember the engine needs periodic valve adjustment.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Sounds like vapor lock, alright.
Another possibility: How's your fuel tank/fuel line? Fine rust can temporarily clog fuel filters and act something like a vapor lock.

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"When you find a big kettle of crazy, it's best not to stir it." - Pointy-haired Boss

1964 Valiant V200, 225/Pushbutton 904
BBD, CAI, HEI, LBP, AC, AM/FM/USB, EIEIO

Smart question, slantvaliant. Another thing to check is the fuel tank venting. Next time the car stalls, take off the fuel cap and see if it'll restart.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

We put the best out of the two gas tanks in the Dart, and washed it out with water and then let it dry in the hot Arizona sun. We repeated this process a couple of times with the sending unit and fill neck removed.
Once we could see that the inside was clear of any sediment etc. we replaced all the rubber and left the pickup screen off.
We installed the fuel filter before the fuel pump to avoid clogging it.
It has been replaced several times since last year due in part to the poor mans method for cleaning the tank.
Where the factory filter goes it has been replaced with rubber fuel line only.

Also, when it did die the last time the carb was hot to the touch as well as the metal fuel line connected to it. The line from the pump wasn't hot.
Yesterday we bought a 160 degree thermostat and coolant.
My son is going to flush the radiator, replace the 180 with the 160 and see if we can't bring the operating temperature down. Going by the gauge it's running a little higher that I would like. Thankfully the gauge is pretty accurate. Last year before leaving AZ. the Dart would run hot until we replaced the water pump. The one on the motor had the impeller reversed !!! It brought the temp. down quite a bit but still not reading below "straight up".
Because the Dart had a 273 originally we had to use the V8 radiator and keep the slants fan. We were lucky to find hoses that worked great.
The radiator may need to be rodded out or recored, we'll know soon enough !
I'd like to have a shroud for it but it looks like that will have to be fab'ed.

I do like the fuel line mod but I'm going to wait on that.

If it dies again we'll try removing the gas cap to see if it has a venting problem. I'll post the results from the thermostat swap, etc.

Thanks again for all the replies.
Lee

This setup is causing your problem. It sounds like you didn't get all the crud out of the tank, but even if you had, you need to have the pickup screen in place, and you need to not have a fuel filter before the fuel pump, and you need to have a fuel filter in place after the fuel pump. The pump is a much more efficient pusher than puller, and the restriction you've added before the pump is causing your problems.
No. All this will do is worsen fuel consumption and engine wear. Use the correct 180° thermostat (preferably a Stant SuperStat #45358) with 50/50 coolant/water mix.
The factory gauges are not at all precise, but unless you're starting with the needle up near "H", lower is not better. You want to shoot for the gauge needle to ride near the middle of the normal range, as indicated here by the *:

C|___|__*__|__|H

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Thanks for the reply.
What i meant by "straight up" is where you indicated the gauge reading with the *.
The Dart usually runs between the * & the H.
To me that's too high!
I can move the fuel filter back to the factory location and see if that helps......
We'll also hang on to the 180 stat and replace it if the 160 doesn't help with the high temp problem.
I'm still waiting to hear from my son about his progress from yesterday.
I'll keep you posted, Thanks.
Lee

apairof66s,

Mine used to vapor lock just running up to the local grocery store. Come back out and you would have to crank it over, and over, and over. If you were lucky it might start. If not you had to wait till it cooled down. The fuel line mod Dan suggested is a big help in hot weather. Just getting rid of that steel line running along the block is a big improvement. So is a heat deflector under the carb to keep it cooler. There are several ways to make them, I used aluminum and the 1/2" thick gaskets top and bottom. After doing both mods it starts right up hot!

Click on the red link below my name for a few pictures. I run a Perma-Cool fuel filter/water separator as well since our local gas station tanks are not the cleanest. The 180 stat Dan recommends really helps during the summer and save the 195 for the winter.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

That does sound too hot.

There should be no difference in how hot your vehicle gets with a 160 or 180 thermostat since that has no control of how hot your car can get, that thermostat only controls when the radiator will begin seeing flow for cool off. Assuming that the thermostat is working properly and not sticking closed, it sounds like you have other cooling system issues or gauge/electrical issues. I'd get an accurate gauge on that and if you are still running on the hot side its time to check the rest of the cooling system for malfunction.

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74 Dodge Charger 225 factory A/C auto 1920 carb stock exhaust.

Mods;
HEI, MSD B3, Magnecor 8 mm, ZFR5N, .060 rotor, CH410X cap, new 3874814 dist, fuel mod, valves hot .010 & .020, all new hoses, JP chain, brake hoses and fluid.

UPDATE :
Drove the Dart a few days ago and it's doing fine.
My son & his friend reverse flushed the cooling system, started by removing the thermostat housing. They replaced the stat with the 160
and filled it up with 50/50 water and coolant.
They also put the fuel filter in the factory location.
This time they bought a metal filter instead of plastic.
It was over 90 degrees when I drove it and the temp. gauge stayed below * or straight up. This is the first time that the gauge reading stayed that low.
After talking to my brother-in-law (25+yrs. as a mechanic in Phoenix)
he agrees that the temp. gauge is working properly but may be off 10 degrees either way. That's close enough for me with the Dart.
We were both working on the problem with the motor running hotter than it should and contributing to the vapor lock.
He also agrees that the radiator may need to be flow tested, etc.
It's the only part of the cooling system that hasn't been replaced or checked.

If it were my car I would get that 160 thermostat out quick and put the 180 back in.
Frank

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Scrapple: Because a mind is a terrible thing to waste.
73 Duster - Race Car
66 Dart Wagon - DD
178" FED
82 D150
All Slant powered

Thanks for the reply.
I do agree that the 160 stat may not be the correct temp. for the slant and I will put a Stant SuperStat #45358 in. But it will have to wait until I can get the radiator flow tested, etc.
For now the Dart is running great with the setup that it has now.

If your fuel pump is old and has a weak oe broken spring the pressure will be too low, and it will vapour lock very easily. I have chased problem before and that was all that was wrong. It can also cause a lean condition since it will lower the fuel level in the bowl, just like having the float set to low.

It's highly unlikely (to the point of near-impossibility) that the fuel pump spring could weaken to that extent. A much more likely cause of fuel pump-related fuel starvation is a worn eccentric on the camshaft, which does not operate the fuel pump arm through a full stroke. This reduces the volume of fuel delivered, but does not appreciably affect the pressure.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.