vapor lock in carb??

[greenrt_se]

head shield under intake,1/2" insulating spacer under carb,tomorrov 170F thermostat,head are edelbrock alu,intake edelb,alu waterpump housing aluminium,visco fan whit tunnel

[cudaken]

 Grouseman, here again, we know something driffrent. I got my 68 Road Runner in 1973 from Mon and Dad with 48,000 miles. She never went over 180 wih 2 row stock in traffic and on the road 170. I will ad I still have her with the 4 row I spoke of.

My old 42sick with the good 3 row stayed in the in the 170 range as well. 1970 Cuda 383 with 3 row all so 170. With the cloged up 3 row the 69 Charger did hit 210 and did not vapor lock, but I  knew she was hot, oil PSI dropped like a rock.

I do think the Charger is running a little cool at 160. I know the pistons need to heat up and all that happy stuff.

Does not matter if you or I am right, just what we know. My self, 170 is where I like it for old cast iron motors.

                                        Cuda Ken

[Ghoste]

I think different engines like different temps too Ken for reasons that no one knows.  I had a 440 once that always ran best hot.  Just over 200 was where it ran the fastest, smoothest and got the best mileage.  Never knew why, it just did.

[greenrt_se]

the motor runs great whit 190F,but after shut down and around 30-60 min try to start again,then the problem is on.the intake is damn hot

[grouseman]

Looking back at the original post, I realized you didn't explain very clearly what is happening when the engine won't start. 

Is it harder to turn over when hot?  Does it turn over as quickly as when it's cold?  Does it struggle to catch, like it's flooded?  Does lots of black smoke come out if it fires?  Does it run rough until it clears itself out?  Will it fire if you keep it floored? 

I'm now almost wondering if you mean that the starter barely turns it over . . . could be over-advanced initial timing or starter/battery problems. 

Yes, the intake will be HOT.  Even 160F is HOT to the touch.  But the carb should be nowhere near that hot, you should be able to touch it and not think HOT. 

Ken, I know what you mean, some engines and cooling systems just handle things better than others, while others struggle.  But there should be an explanation for it all.  A buddy's 350 Pontiac (new to him and rebuilt right away) overheated from day one, even while idling.  The needle would just keep climbing - 230, shut it down.  Put in a 160 thermostat, no change.  Took out the thermostat, no change.  He put in a big alum rad, no change.  He put on an electric fan, no change.  Went through the timing and found the balancer had spun, which accounted for a lot.  But it still overheated.  Finally realized that there is supposed to be a plate sandwiched in the water pump which was missing - directs flow around impeller.  Put it in, and suddenly his problem was it wouldn't go past 150F!  I know it's not related to this problem, but there's a solution to be found here.   And the lesson learned was don't assume anything, and brainstorming was the key to solving it. 

grouseman

[greenrt_se]

it just no start,starter turning motor ok,like cold engine,when temp going down no black smoke,just normal start,when hot after driving,pedal to the floor don`t help,squiters give a good shot of gas  ,after cooling no rought running

[cudaken]

 Green RT, this is going to sound a little dumb, but want to try my cross flow? As you may know from my posting here my fresh 440 is coming back out. I figuer if I am lucky it will only be down 2 weeks, and that is if I am lucky.

You would need to drill some holes to use it, but I am 95% sure it will fix the problem. Besides, more likely to get hurt sitting around in the garage than on a Charger. If you have a 727, I will send the cooler as well.

Send me your address and it's on it's way.

                     Cuda Ken, the Cool

[cudaken]

 I will also send the hose's as well. No reason for you to spend any money for them.

                                   Cuda Ken

[deputycrawford]

I had the very same problem with my 69 charger. It also has a Race Demon, Edelbrock PRM intake and a Carter 120 GPH fuel pump. I would shut the car off and try to start it 30 mins later and fuel would boil out of the rear bowl. I started to shut it off and open the hood for the 30 Mins. it fixed the problem. I called Paddock and ordered the fuel sending unit for 1/2 inch feed line and the built in 1/4 inch return line. From the fuel pump I run the 3/8 inch fuel line because I went to NAPA auto parts store and ordered a fuel filter with  3/8 inch fuel line in and out and a 1/4 inch fuel return line for only $8. I ordered the 1/2 inch aluminum fuel line and the 1/4 inch aluminum return line in universal coils and ran the lines myself. POOF, problem solved. The sending unit cost around $135 and the other stuff cost around $60 but the car never did it again. Well worth the money. And I should never have to upgrade the fuel system again. I hope this helps. I even run the fuel log attached to the carb and a fuel pressure regulator. The stock vehicles had the same problem and the factory made a factory alumiinum foil rapped pillows to put under the intake when new. The return style system of the R/T fixed the problem when new. It worked for me when old too.

[greenrt_se]

thanks.when I made new fuel line ,I keep original line still in place under car.so now I have to just made return line from carb to end of the old line

[greenrt_se]

also I made spacer under the carb

[deputycrawford]

No problem. Like I said, I even have the Demon carb and the same 8AN fuel log I see in your picture. Just make sure your old line isnt too big. 1/4 in is plenty of line. Bigger than that and you wont hold any fuel pressure on the bowl seats in the carb. I also have the Carter 120 GPH mechanical pump with an electric fuel pressure guage. At idle it barely keeps 6 lbs pressure. If I had the bigger return line the fuel pump couldnt keep up. You had the right idea when you first  posted your problem. Run with it and Im sure you will work it out.

[cudaken]

 Timo, here is a little test for you.

Bring the engine to say 170, shut it off. Let it sit say 5 minutes. Start her back up, is the problem still there? I will bet it is not.

Humm, Finland. Does my cross flow need a pass port?

                                Cool Ken, posting again

[greenrt_se]

I put yesterday 170F thermostat,and it seems to help to solve my problem,but right now the wheater here is cold,and maybe it better at I
buy during winter good aluminium radiator.
cudaken.just drive to Alaska,and throught the Russian,it`s only 20minutes to drive my house after Russian.And thake yours radiator too

[cudaken]

 Hope that soulves the problem Timo. Lets see, if I leave right now I should be there in Januray.

                                        Ken

[greenrt_se]

ok.sauna is on ,and while you drive through Moscow,buy some vodka and caviar

[cudaken]

 Timo, I must say I had fun with this post. Hope to hear the problem is gone this summer, as well as mine.

                      Your friend Ken

[greenrt_se]

ok driving around town last night,stop the motor let is stay 5min-30min, start great.meet guy who make aluminium radiator and intakes from aluminium,he make radiator for me in next winter
so I have a lot of work for winter
-keisler 5 speed
-dash refacing
-chance carb jet a little smaller

[Ghoste]

I love that photo.  I don't know why for sure, but there is something about it that is just very appealing to me.

[greenrt_se]

damn,it make it again ,shut down hot (170F) motor ,and after almost 1hour don`t start defore I put a lot of gasoline in (pushing gas bedal to the floor many times) and then it fired up very slow.The carb is rich side(I have a A/F meter in center console) and plugs are NGk bcp5es

the intake isn`t hot,like it was whit 180f thermostat

[grouseman]

Is there a crack in the carb bowl, letting the fuel slowly drain out into the intake? 

grouseman

[greenrt_se]

carb is brand new demon,iwhile motor running I been searching vaacum leak around carb no found

[greenrt_se]

and the fuel level is ok in the bowls