Cranks good but pops only on one cylinder

[REX55nord]

Hello all,

 

I haven't posted in a while, but this one has me flustered.  The engine is a 1955 Chrysler Industrial Model 30 (230 ci).  I rebuilt it completely and it ran perfectly and started instantly..  Went to start it after sitting over winter and she cranks nice and fast (has the 12 volt system) but sounds like it's popping (firing) only on one cylinder; and she occasionally shoots a fire plume out the exhaust.  The coil and resistor, even with the ignition switch off, became extremely hot, so I double checked all the wiring and then replaced the coil and resistor, and replaced the switch ...no difference.   The fuel pressure seems ok, although I haven't checked it with a gauge....as far as I know the timing is correct and nothing else has changed since it last ran.  It does show a lot of gas down in the manifold.  Your ideas would be much appreciated!

[48mirage]

Fire out the exhaust is too rich.  Has your float stuck on the carb?

[REX55nord]

No, I opened the top of the carb...it's not stuck.  

[DJ194950]

 1 Easy check, remove the cap and look for moisture/corrosion of cap,rotor,points. A moist cap allows the spark to go where the least resistance is. Usually the plug with No compression.

 

DJ

[Plymouthy Adams]

remove and clean or replace the plugs..you could well be splashed fouled at this time...

[greg g]

Just because the float is not stuck, does not assure it is opening and closing the needle and seat valve as it should.

[Plymouthy Adams]

you are right Greg but the man said there was PLENTY of fuel down in the manifold..leading me to think he is super flooded and now has fouled plugs..

[REX55nord]

Thanks for all the replies.  I do wonder if the needle valve is properly closing.  Also, as stated, there may now be so much gas present that it will take a while to dry out.  I will sleep on it...sometimes it takes that. 

[Niel Hoback]

^{Once you have the top off the carb, its easy to lift the float out and shake it good.   Hope for no sloshing sounds.}

[Jerry Roberts]

After siting all winter are some of the valves stuck open ? You might pull the valve covers for a look , or perhaps it is easier to do a compression check . 

[REX55nord]

Thanks again....still looking into this - it does have good compression.  Also, I checked the float and it hasn't taken on any gas (inside).  Right now, I'm checking all the wiring especially the starter/switch/ammeter circuit, because I just discovered that the ignition seems to be still on even with the switch turned off - a short of some kind??  Note that the one elect. component I have yet to swap out is the condenser...I'll try that as soon as I can get back to it.  Having said that I haven't ruled out fuel side....I plan to double check the float level and fuel pressure.  The carb is nice and clean and was rebuilt when I did the engine.  As said before, this engine was running perfectly - it would start almost 'before you hit the starter button'.

[Don Coatney]

After siting all winter are some of the valves stuck open ? You might pull the valve covers for a look , or perhaps it is easier to do a compression check . 

If an engine has no compression on one or more cylinders it is easy to tell by listening to the starter. If all cylinders are up on compression the starter will spin at the same speed. If there are cylinders short on compression the starter will spin faster when those cylinders come up on the compression stroke and there is no compression. Very easy to hear this.