Bad running 318

[roadripper]

A friend of mine has a 318 in a shunt truck , it is hard starting and runs like crap until it gets warm !! Once they shut it off and try to restart 15 min later it's very hard to start again ,
So they have replaced the timing chain and gears , new two barrel carb , wires ,plugs etc
- they also have an electric fuel pump (with no regulator ). ??? So I figured electric pump is too much pressure for the two barrel ? Also thought maybe the intake was plugged with carbon at the base of the carb ? But then noticed they have a 3/8 line plumbed from the water pump housing into the base of the intake ??? Never seen that before ? Anyone have any ideas ?
Thanks mike

 

[teringer]

could be a week coil ,they will fire a rich fuel mixture like when the choke is on , and have a hard time when the choke is off after warm up and a leaner mixture , or coil wires reversed will do the same.

 

[younggun2.0]

did they just throw a timing gear at it and install it straight up? i suspect they used a cheap one. they cheaper the set the worse the quality control/accuracy is. also sounds like it maybe way advanced. did it sit for a long time? maybe cap/rotor got moist inside? change the plugs and wires?

need air/fuel and spark to run an engine. the rest is tuning.

 

[Dartnut]

The heat crossover under the carb and heads is likely plugged with carbon etc.
This is common on all small blocks.
Take the intake off and clean all of the gunk out and you'll be surprised at how well it runs after that........

 

[roadripper]

First thought was pluged intake but the water line going into the base of the intake by the carb thru me off . Not sure about the coil will have to check that out, aperently the cap , rotor and wires are new

thanks for the help. Mike

 

[Rapid Robert]

choke closes all the way when you put the pedal to the floor one time to set the choke? choke opens a bit when it starts (choke pulloff distance between upper edge of choke plate & carb inside housing wall)? eng runs fine after it warms up??? When cold it idles poor or runs poor? (or both)

 

[roadripper]

manual choke on this one ,runs fine after it warms up , but if you shut it off its areal pain to start ?

 

[AJ/FormS]

That looks like a heated-water intake.A carbheater.Seen it on a Ford once.It works similarly to the exhaust crossover.
Your problems are more than one.
-The hard hot-start could be fuel percolation.Are you running the correct fuel?
-The crappy cold running? thats a toughie.Sounds lean. Does that carb have an adjustable metering rod system?If yes crank them up a bit.
-Also make sure the initial timing is generous, and that the vacuum advance can is working.
-Whats a shunt truck? What year is it?

 

[pishta]

float level and fuel pressure. Check them both. Usually a high pump pressure manifests itself as a motor that eventually bogs and dies, then is near impossible to start hot. check fuel level. high level runs rich, great for a cold motor but not good for a warm one. I bet your level is low.

 

[WoodenNickle]

You were right the first time. Carbon under the carb. You will have to take the intake out. Flip it upside down. Pull the ste3l plate of the valley area of the intake, and you'll finger enough carbon there that looks enough like coal, that you'll try to sell it to a power plant. Clean that out and you'll be fine.

 

[TXDart]

That fuel line is resting on the valve cover and where does it go from there?
Hope it not near the exhaust....Where is the fuel filter located?
I had bad luck with the see thru glass fuel filter on getting hot and vapor locking....
What your fuel pressure ? Low pressure will cause vapor lock.
Just throwing out ideas...Good Luck