Engine trouble

[msarnold1990]

So this is probably my fault.  I forgot to add oil this morning as I figured oil level was still fine since I added more last week. This is my first Classic, so I guess we all learn the hard way. 

 

I was driving on the highway and heard two loud bangs from under the hood. Car instantly slowed down to 20mph and will not go any faster than that, runs very very rough. Anyone have any idea what I could have screwed up?  I'm sure it's not good. 

Edited August 15, 2021 by msarnold1990

[Sniper]

the list is almost endless.  Could have been a back fire that messed up the carb.  You may have lost a plug wire.  Doubtful you threw a rod because that is usually followed by a large oil spill, smoke and no more running.

 

Did you look under the hood?

 

 

[Young Ed]

I would guess if the loud bangs were caused by lack of oil your engine wouldn't run and all and would probably have a new window in the block. 

[msarnold1990]

Yes and it looks normal. There was some white smoke coming from the tail pipe. I managed to drive it another 2 miles to somewhere safe. When it idles it rocks pretty significantly and will not accelerate past maybe 20mph. 

[Sniper]

Start checking things. 

 

Are all the plug wires attached, both ends?  Any of the plugs come apart?

Check your oil level.  What is your oil pressure?

Does the muffler look like a popcorn kernel that popped? 

Takes the air cleaner off and inspect the carb, look down the throat at the butterflies.  Is the choke stuck shut?

 

We can't look for you, so you're going to have to eyeball things and report back. 

[RobertKB]

White smoke from the tailpipe could indicate a blown head gasket but not necessarily the noises.

[Dodgeb4ya]

Head gasket...

[msarnold1990]

So I managed to get the car home. Things I noticed. 

 

White smoke from tailpipe

Tailpipe intact and fine

Sparkplug wires are connected correctly, nothing popped out

Gas around the outside of the carburetor

Stalled badly on hills and needed max throttle to get it to start 

Managed to get it cruising to 30mph but will not go faster.

When it stalled I had to close carburetor to let it fill with fuel, then open it and pull the throttle. 

 

Also, I ran out of gas this morning. I have a feeling something got sucked into the fuel lines and messed up the carburetor or something in the engine. 

 

 

<mod note>  watch the language....foul language edited

 

 

[greg g]

Do a compression check.  Suspect blown head gasket.

[allbizz49]

How low are you on oil? Probably has nothing to do with your problem, just curious.

[knuckleharley]

1 hour ago, msarnold1990 said:

Yes and it looks normal. There was some white smoke coming from the tail pipe. I managed to drive it another 2 miles to somewhere safe. When it idles it rocks pretty significantly and will not accelerate past maybe 20mph. 

White smoke? Have you checked your oil for both the level and color? Should be a normal dark color. If it looks cloudy/gray,you have water in your oil. Most likely from the water distribution tube in the block being rusted out.

 

I don't know what to tell you about it only running 20 MPH

 

BTW,what type,brand,and weight oil have you been using?

[Sam Buchanan]

54 minutes ago, msarnold1990 said:

 

When it stalled I had to close carburetor to let it fill with fuel, then open it and pull the throttle. 

 

Maybe I'm just dense, but I don't have a clue what the above quote means.........

Edited August 15, 2021 by Sam Buchanan

[msarnold1990]

I meant I closed the choke, let the fuel build up, then opened it and the throttle. 

[msarnold1990]

What kind of head gasket is used on these flathead 6 engines? I'm guessing it's the head gasket. Is it a sort of easy repair? I'm assuming not. 

[Sam Buchanan]

5 minutes ago, msarnold1990 said:

I meant I closed the choke, let the fuel build up, then opened it and the throttle. 

 

This was with the engine running or off? What are you describing as "when it stalled"? The engine lost some power or it quit?

 

You may have a fuel flow issue. The loud bangs may have been backfires as the engine ran out of gas???

Edited August 15, 2021 by Sam Buchanan

[knuckleharley]

Just now, msarnold1990 said:

I meant I closed the choke, let the fuel build up, then opened it and the throttle. 

Ok,it sounds like in addition to any other problems you might have,you also need a new fuel pump. There is also the possibility the diaphram has cracked and allowed gasoline to flood the base pan on your engine. Remove the dipstick and see if it smells like gas. If it does,do not try to start the car again until you have replaced the fuel pump and drained the crankcase and refilled it with 30 wt non-detergent oil.

[msarnold1990]

This was just trying to start the engine. 

[Sam Buchanan]

11 minutes ago, msarnold1990 said:

This was just trying to start the engine. 

The carb won't "fill" with the engine stopped because the fuel pump only functions with the engine running (unless you have an electric pump).

 

You may not have run the tank dry this morning. You may have experienced a clog in the fuel system or a failed pump. Take the fuel line loose at the carb and put it in a bottle. Disconnect the hot wire from the ignition coil and crank the engine to see if a strong stream of gas is flowing from the pump.

 

I can't explain the white smoke.....losing a head gasket and fuel pump at the same time would be quite the coincidence.

Edited August 15, 2021 by Sam Buchanan

[Sniper]

White smoke, which is steam not smoke, especially on a cool humid day is not uncommon until the engine and exhaust system warm up.

 

Before we start jumping on head gaskets or fuel pumps let's try some tests.

 

3 hours ago, msarnold1990 said:

Gas around the outside of the carburetor

 

Tells me you probably have a stick float.  Check that before you go haring off into what if's.

 

 

[keithb7]

Re wet areas around carb:

 

Maybe  leaking carb gaskets, or fuel line connections? Could it a be thin film of oil from a sweating or weeping oil bath filter housing? Fuel evaporates. Oil does not.

Any comments on your wet carb areas related to this info?
 

Burning coolant has a certain sweet smell. When coolant burns it deposits sodium in your crankcase, often found in oil lab analysis.  How’s your exhaust smell when its steamy? Don’t inhale a big huff!

 

How goes the oil on your dipstick look when you pull it? Oil color? Is the coolant level in your rad dropping?

 

Like Sniper said...Could be a million things. Good Troubleshooting will determine the proper path to a repair. 
 

I like to start with a compression test. That’ll set the playing field early. 

 

[DJK]

14 hours ago, RobertKB said:

White smoke from the tailpipe could indicate a blown head gasket but not necessarily the noises.

unless it is blown between cylinders, that can make quite a noise.