Can anybody solve this hot start issue? I'm out of ideas!

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67Dart273 said:
I think the cause is probably simpler than you think. The 4140 style Holleys have the float bowls up away (not in contact) with the manifold, and surely must get SOME airflow, as well as "not so much" conduction through the metal of the manifold/ carb

Edelbrock, on the other hand, is just like a pan on a stove burner.

What you guys discussed in your referenced thread is pretty much just what I did:

Electric pump

Do the best you can with insulating/ rerouting the fuel line

Use a carb spacer/ and insulator

Install a vapor recovery system. The vapor recovery not only keeps a small amount of fuel circulating, it also nearly immediately dumps fuel pressure in the line to zero on shutdown, and provides a path for boiling/ pressure buildup, so that fuel is not so badly forced past the needle/ seats under pressure.

I still have not .....uh.... "finalized" my fuel line routing, and am presently running the electric pump through the mechanical. On very hot days, it sometimes STILL requires a part throttle, 5-10 second crank, but this is intermittent.

I expect that when I remove the mechanical pump, and get the line fully insulated, as well as a little shield between the line/ headers, even this will improve.
Click to expand...


Bingo! Thats how I solved my fuel vaporizing problem fuel pump near the tank pushing the fuel instead of up front sucking fuel which will vaporize it. the fuel in the lines has a hard time reaching the carb after it is heat soaked.
just bypass the mechanical pump it adds heat to the fuel.
 
Find a gas station that sells real gas ( no ethanol ) and it will cure the problem.
 
So many posters missing the point.

THE FUEL THAT IS ALREADY IN THE BOWLS IS THE PROBLEM.

Not routing of fuel lines
Not timing
Not type of fuel line
Not whether it goes through a mechanical first
Not the insulator type, if any
Not whether your pump sucks or blows (had to say that)
Not location of the pump

Gas without ethanol, and cooler carb base are two of the closest answers to the problem so far.

I don't know if you can get gas without ethanol, but I do know we should be able to keep the carb cooler somehow.
Then again, by the time we finish figuring it out it'll be cooler again. :)
 
TrailBeast said:
So many posters missing the point.

THE FUEL THAT IS ALREADY IN THE BOWLS IS THE PROBLEM.

Not routing of fuel lines
Not timing
Not type of fuel line
Not whether it goes through a mechanical first
Not the insulator type, if any
Not whether your pump sucks or blows (had to say that)
Not location of the pump

Gas without ethanol, and cooler carb base are two of the closest answers to the problem so far.

I don't know if you can get gas without ethanol, but I do know we should be able to keep the carb cooler somehow.
Then again, by the time we finish figuring it out it'll be cooler again. :)
Click to expand...
it is hard to convince old school (and i was a non believer) but i fought the same issue. i got connected to the coolcarb guy through a hemi shootout racer when i was down at maplegrove raceway. he had one on his 440 dart. he gave me one to try while i was there. the damn thing fixed my issue literally overnight with float adjustment and 7 psi regulated pressure. i bought 2 more sets recently. i'd be happy to send the OP one to try before he decides to buy one.
 

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TrailBeast said:
So many posters missing the point.

THE FUEL THAT IS ALREADY IN THE BOWLS IS THE PROBLEM.

Not routing of fuel lines
Not timing
Not type of fuel line
Not whether it goes through a mechanical first
Not the insulator type, if any
Not whether your pump sucks or blows (had to say that)
Not location of the pump

Gas without ethanol, and cooler carb base are two of the closest answers to the problem so far.

I don't know if you can get gas without ethanol, but I do know we should be able to keep the carb cooler somehow.
Then again, by the time we finish figuring it out it'll be cooler again. :)
Click to expand...

Well, I would say "I'm not disagreeing with you", but it's NOT not all those other things, it is in fact ALL of them, including fuel in the bowls

By the way I called Clifford Performance today, and told them, "I'm an old guy, sometimes I imagine stuff. Didn't you used to sell water jacketed carb spacers?"

The answer was !!!YES!!! We used to!!!

Guess I"m gonna havta make one.
 
67Dart273 said:
Well, I would say "I'm not disagreeing with you", but it's NOT not all those other things, it is in fact ALL of them, including fuel in the bowls

By the way I called Clifford Performance today, and told them, "I'm an old guy, sometimes I imagine stuff. Didn't you used to sell water jacketed carb spacers?"

The answer was !!!YES!!! We used to!!!

Guess I"m gonna havta make one.
Click to expand...

"it is in fact ALL of them"
Not really, because after the gas has been in the carb for a half hour it doesn't really matter what happened on it's way there does it?

We kinda hit on that a bit earlier also.
My thoughts were that if the 180-210 heatsoak is causing this, then the coolant temp in the spacer is still going to be high enough for it to still cause the same problem since the coolant is not going to be any reasonable amount cooler than the engine block. (especially after shutdown and the temp goes up) JMO
 
drive48 said:
it is hard to convince old school (and i was a non believer) but i fought the same issue. i got connected to the coolcarb guy through a hemi shootout racer when i was down at maplegrove raceway. he had one on his 440 dart. he gave me one to try while i was there. the damn thing fixed my issue literally overnight with float adjustment and 7 psi regulated pressure. i bought 2 more sets recently. i'd be happy to send the OP one to try before he decides to buy one.
Click to expand...

shoot if he dont want it id be happy to throw it on mine and report back on how well it works LOL

that looks like it would cure my problem
 
Maybe we need a "dry sump scavenge pump" setup for our float bowls LOL
 
I pretty much decided to live with it, then everybody jumps in with suggestions and even an offer. I don’t mind being the guinea pig. I did some further testing this week without resolving. I wanted to respond to a few suggestions. This issue is mainly an annoyance.

1) I blocked the exhaust crossover; coolant temperature is down to 200-204.
2) I changed the rods to #24 Jet 1427 (.098") Rod 1456 (.073" x .047"). Checked floats. Cruise rich 1 step.
3) I always use no ethanol gas.
4) Put in Autolite 65. Actually idle is smoother… go figure.

Current status; starts a lot quicker, less than 5 seconds. I crack the throttle slightly open it starts immediately. I'm going back through thread again and see if I missed anything. drive48 and TrailBeast PM sent.
 
Can you post a sound bite of start up ? At least then we could hear if it is the normal old car that's hot start up , or you really have a problem . In the morning cold it starts faster than after driving in 80deg heat and starting , it cranks a few times more than when cold , it's not exactly like new cars that start the same hot or cold . At least that;s my experience .
A spacer and or heat shield can't hurt , same with electric fuel pump , even if only used for starting then letting mech pump take over .
 
my5thmopar said:
I crack the throttle slightly open it starts immediately. .
Click to expand...

I cannot remember when I did NOT do this on any of my older, non - EFI 'rigs.'

I actually had to train myself to keep my foot off the gas on my first EFI car.
 
Mine in the morning, key and fuel pump on, wait till pump pressures up, twice to the floor with the pedal and it fires up before I can let go of the key almost.

When over 80 out, I turn off the car, go in a store for 1/2hr or so, get in it and turn the key, 1-2 cycls hit then none, hold the gas open a little and crank for about about 4 seconds and it fires up, tries to stall and runs really rich and smells like gas till I get that existing fuel out of the carb, then it's fine again.

Closest I can describe it.
 
Not Knocking the eddy carb......ran great till I go into the store, come back out and have to hold to floor till it finally starts....embarrassing....installed holley.....problem solved, wonder if we could get some of those viton tipped needle and seat dealies for an eddy carb???
 
I'm a lil late to the party, but I too have battled this same problem for years in my truck so I feel compelled to bumb. My truck will start instantly when cold or hot (less than 110 but hotter than 160), but once it sits for 30-60 min (110-150) it'll wana start but dies right away. Hard to explain, almost like 2-3 cyl hit and dies, if you don't catch it at that point w/ a 1/8 pump it'll crank for 5-8 sec (Yes VERY embarrassing). Only way to get it to start quicker after the initial fail is WOT, and than its really loaded up, not to mention it trips the high idle cam so then I have to sit there at 1200-1400 rpm for 4-6 sec. Makes me look like a jack@ss, like I'm intentionally reving it for no reason. Only experienced carby people understand what I'm doing. Guys at work give me grief every winter when the go to start their cars and my trucks already on its 3rd stage of high idle (1800-2000 rpm). Hey, your trucks about to blow up, is your throttle stuck, its about to take off in to orbit ect. So when they hear it struggling on hot starts, it just adds insult to injury. Sorry for rambling lol I sure hope we find a sure fix and not just a some bandaids. I've just learned to deal with it :/.
 
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