69 charger missing at high speeds and boiling coolant

[Dukeboy]

I feel like I will never get this car on the road. Every time I fix something, I find something else wrong. I have a 69 charger with a 1970 440. It misses at high speeds and today I brought it home and the coolant was boiling. Recently I replaced the plugs, wires, distributer cap and rotor, fuel pump and fuel filter. It misses at around 40 mph and I flushed the radiator about 2 yrs ago. What the heckfire is going on with this thing? Any help or questions are appreciated.

Neal

[b5blue]

Did ya change the plugs? You can "read" them to see how things are burning.Where is the timing set at...maybe check to see how your advance is moving it might be stuck or gummed up. Don't get frustrated you will be glad when you work the bugs out, lack of advance will build up heat.

[flyinlow]

Welcome to the world of 40 year old mopars.  Take a break ,have a beer, and tell us your problems.  You will fix it.

It misses at 40 mph only? cruising or hard accelleration? What rpms.

If you are boiling over with antifreeze/water and a preasure cap on ,thats pretty warm.

Read the plugs

Look for ignition grounding on engine at night. If auto ,have someone put a load on the engine in gear for short periods.
Check near headers if installed.

Check timing and advance.


What radiator/fan/shroud?

Need more info to help with whether you have one problem causing both conditions or two problems.

[Hemidog]

Sounds like you need to adjust your timing, both symptoms can be caused by bad timing.

[Rolling_Thunder]

agreed on timing...         

[mopar0166]

kinda the same thing happened to me today, but i think my timing needs to be adjusted some more

[mjwebb]

coil perhaps? or do they just go out intead of deteriorating

[Chryco Psycho]

I agree with timing , if you have vacuum advance either disconnect it completely & advance the initial timing up to 16* or at least6 make sure the vacuum advanc ei sconnected to ported vacuum that rises with RPM  Not manifold vacuum that drops with RPM

[Dukeboy]

Thanks for the responses. Just to give some more info, the engine is a 1977 440 and the timing calls for 10 deg above TDC but I set it at like 12. Shouldn't make that much of a difference, but you never know. I did think of the coil, thank you. I bought one today and will try that. The car purrs like a kitten when idleing and it really takes off when I floor it, but when it hits third gear and is under normal driving speeds it feels like it wants to conk out. I replaced the plugs, wires, distributer cap, roter, rewired the entire car, electronic ignition box, volt reg, fuel pump, balast, carb hoses, and etc. The car was at paint for over a year and sat. Could the thermistat be stuck? Sould I flush it again? Please help. I waited so long to enjoy this car and now everytime I fix something I find another problem.  My dad still has his 69 charger he bought brand new with the money he got for being in the marines in Vietnam. It is a numbers match 383 with 52k miles. It would be great to cruise with him. Thanks guys, let me know if anymore info is needed.

Neal

[flyinlow]

A 1977 440 would be  low compression stationwagon engine . You should be able to crank the timing up to 15-20 base before it knocks on 92 octane.

[b5blue]

Replace the T stat or run without for a test. Are you using the vac adv? If you are make sure it is from carb not manifold vacuum. Try time by "ear" rotate till high idle and back off a little.Check to make sure you don't have a "lean burn" dist in there.(not 100% sure but they don't have a vacuum pod on the side I believe) 

[flyinlow]

440 engines use a push rod to work the fuel pump . Sometimes the shorten with wear and the fuel pump does not put out much.

Try a fuel pump delivery test.

A crude radiator flow test is to drain the cooling system. Disconect the lower lose. Plug the lower hose neck ( use your hand), fill the radiator with water,then remove the plug. most of the water should drain in 5 seconds or less.

[Rolling_Thunder]

is it a un-rebuilt engine ?    if it has the stock timing chain it may be worn / jumped a tooth or two ?

[Dukeboy]

As far as I know, the engine has not been rebuilt. The guy I got it from was a shade tree mechanic and thats being polite, idiot is more like it. I tried replacing the coil, but that made it run so bad it stalled and would not stay running. I put the old one back on and it purred like a kitten. It has a vacuum advance on the distributer and the hoses are correct because we switched em just to see and it was 10 times worse. Today I drove it again and it is still missing at around 40 mph and higher. We double checked the new wires for firing order and I did add a little more coolant. It did not boil today, but it is hot. My neighbor recommended taking the thermastat out completely because I only drive in the summer. It this a good idea? Do I need a thermastat to also keep it cool or would this work? Maybe  a lower temp thermastat instead of a 195? You guys are really helping, keep sending me your ideas. Thanks.

Neal

[flyinlow]

180* thermostat is a good choice