340 runninng lean and overheating

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V3gard

V3gard

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Hi

So I have been lurking around this forum for quite some time now, after buing my first v8 powered car last year. It`s a 340 powered 71 dart, wich last year, ran fine. It has an edelbrock inlet maifold and QFT carb. For the winter I wanted to mount headers, wich proved to be quite a challenge as things was very tight!

Ended up removing the heads to be able to fit them. Got it all together last week and this is when the problem occured. Now, I am very unfamiliar with V8`s, so consider me a newbie.

As I fired it up for the first time the idle was good once it got up to temperature, but when I give it a little throttle, there is almost no power, and it sounds like a machine gun. Loads of backfire perhaps, and temps going very high very fast. So, I check the plugs and they are very white indeed.

I have checked the distributor cables going to the correct cylinder in the correct order 3 times, all seems good. I guess the problem is either ignition or carb related? I am wondering what I can have done wrong when I assembled the engine? I have tried to search the forum but cant quite find any answers that I understand :)

Also, English is not my native language.

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Post a close up picture of a couple of plugs if you can. Get as close as you can to the porcelain so we can see it. It has to be very shiny white before you are lean.
 
yellow rose said:
Post a close up picture of a couple of plugs if you can. Get as close as you can to the porcelain so we can see it. It has to be very shiny white before you are lean.
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Will do as soon as I finish work!
 
Maybe.
My first guess would be inusufficient timing.
 
Mattax said:
Maybe.
My first guess would be inusufficient timing.
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Yes.... I was thinking that the ignition timing is very retarded. Advance it to +15 idle timing and try again it again idling. Don't drive it around a lot with this timing until you have found out the total advance timing at higher RPM's when sitting still.
 
Thank you both of you, I will have a look aty the timing later today :)
I just cant understand how the timing has goten so messed up, when I supposedly did nothing to cahnge it :/
 
What do you mean by 'going very hot very fast'? Is this info from reading the temperature gauge?

And your English is good!
 
Also double check plug wires 5 & 7 very easy to get crossed up.
 
V3gard said:
Thank you both of you, I will have a look aty the timing later today :)
I just cant understand how the timing has goten so messed up, when I supposedly did nothing to cahnge it :/
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The engine ferries come into your shop at night and screw with stuff. It’s either them, or my wife. But I can’t catch either, so I can’t say for sure which it is.

Sometimes they just break in the shop or in the trailer.
 
Took me a minute... a ferry is what you ride on the water. A FAIRY is what messes with your engine.. or another fairy.. LOL

Now the 'wife theory' has some real merit....
 
nm9stheham said:
Took me a minute... a ferry is what you ride on the water. A FAIRY is what messes with your engine.. or another fairy.. LOL

Now the 'wife theory' has some real merit....
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I just figured it was the Donnegal accent.
laugh2-gif.gif
 
V3gard said:
Bad gas like in poor fuel quality?
The fuel in it now is 98 octane (supposedly) and has been sitting in the tank since, october last year possibly.
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I had a guy have his car at a body shop for 2 years when came over when it was running smelled like turpentine car would ping like crazy had no power what so ever and it was a 440. the gas had went bad. if the fuel smells fresh then your good
 
Were the carb bowls empty? When the gas evaporates in fall, it leaves behind solids that can plug your idle wells.
If yes; then I think the metering blocks will have to be torn down and boiled in carb cleaner to clear the passages you cannot see.
If you did not stabilize the gas last fall, then take a sample, and check the color; clear is good, red is bad. Orange/pink is iffy, you can burn it in your lawn moper; but not in your boat or chainsaw. Yellow is occasionally hard to start, but OK at Part Throttle.
If your car was stored in a non-heated place, then the fuel tank breathes all winter thru the vent. More if left outside in the sun. The breathing brings in moisture that is in the atmosphere...... which condenses, and collects in the bottom of the tank and freezes to ice. In spring it melts back to water and is the first thing your fuel pump sends to the carb.
 
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nm9stheham said:
What do you mean by 'going very hot very fast'? Is this info from reading the temperature gauge?

And your English is good!
Click to expand...
After a easy, very short drive every part in the engine was extremly hot, and the water was "fizzing" boiling like. The water temp gauge was climbing rapidly so I turned around and shut it off. Maybye I was a bit overreacting but it did not feel right.
 
yellow rose said:
The engine ferries come into your shop at night and screw with stuff. It’s either them, or my wife. But I can’t catch either, so I can’t say for sure which it is.

Sometimes they just break in the shop or in the trailer.
Click to expand...
Hah, yeah pretty sure I`d spot a ferry breaking into my garage, but I can see the wife theory being worth investing :)
 
Slantsix64 said:
I had a guy have his car at a body shop for 2 years when came over when it was running smelled like turpentine car would ping like crazy had no power what so ever and it was a 440. the gas had went bad. if the fuel smells fresh then your good
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The gas smells good to me, but I might as well change it, worth a try!

CFD244 said:
Any chance of a vacuum leak since he pulled the heads and intake installing headers?
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I did use start gas here and there when I first fired it up, and did not hear any rise in rpm. But I will do another try :)

AJ/FormS said:
Were the carb bowls empty? When the gas evaporates in fall, it leaves behind solids that can plug your idle wells.
If yes; then I think the metering blocks will have to be torn down and boiled in carb cleaner to clear the passages you cannot see.
If you did not stabilize the gas last fall, then take a sample, and check the color; clear is good, red is bad. Orange/pink is iffy, you can burn it in your lawn moper; but not in your boat or chainsaw. Yellow is occasionally hard to start, but OK at Part Throttle.
If your car was stored in a non-heated place, then the fuel tank breathes all winter thru the vent. More if left outside in the sun. The breathing brings in moisture that is in the atmosphere...... which condenses, and collects in the bottom of the tank and freezes to ice. In spring it melts back to water and is the first thing your fuel pump sends to the carb.
Click to expand...
The car has been in a insulated garage all winter, with stable temps never dropping below frezzing.
Regarding empty carb bowls, I guess they where. i pulled the carb pretty early on but not sure if it was fully emptied or not :/ The engine runs quite nice on idle, it`s when I touch the throttle things go bad. I could post a video later today.
 
Is it possible there was an issue with the re installation of the heads? Wrong head gaskets, improper torque, etc.
 
krazykuda said:
Could the distributor be 180° off????
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Much more likely its 10 or 20* off.


Coolant shouldn't be 'fizzing'. I assume this is in an overflow tank. Otherwise check the coolant system for whether its holding pressure. 14-16 psi although it varies a littlee with year and engine
 
Nothing to do with your issue, but put another throttle return spring on it.
 
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