Oil smells like gas...

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nodemon

nodemon

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Among the many issues I'm having, I now notice the oil on dipstick smells like fuel.
I know worn rings can cause this, and I do have a "low" compression cylinder, but there's no smoke coming from exhaust. Wouldn't I see exhaust smoke if rings were bad..?
Come on... learn me.
 
Could be the pump itself, either high pressure or leaking. 65
 
Pump could be leaking. DO NOT run the engine. In my lifetime I have seen THREE engines damaged in some way from a crank case explosion.

If pump diaphragm is leaking, it will pump gas into the crank case. other causes you mentioned, carb troubles, running way rich, bad rings, etc.
 
In the 70's I got stuck on Navy shore patrol for 3 months. We had one guy who was ALWAYS late. One morning he came in --late-- and I said, "this had better be GOOD."

He said he sent his son out to start his 57 Chev, loud bang. The thing blew one valve cover off, and blew off the oil filler cap so hard it DENTED THE HOOD. these old Chev SB's had a riser tube with a "slip on" oil breather, quite bulky

Another one I just saw the aftermath of, same thing, bulged rocker covers.

The third, late one Fri/ Sat night we were entering a cafe in my home town, someone in a Ford parked out front cranked it up, and fire and "BOOM" underneath. Blew the oil pan part way off the engine!!
 
I had an issue once where the carb would empty the bowl when I parked the car. The gas would run into at least one cylinder and then past the rings into the oil. Oil smelled like gas, you could tell cuz you needed to crank the engine until the carb filled when you started it cold.
 
nodemon said:
It's a new pump, not that new things can't be defective. Is there anyway to "check" it..?
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I would just replace it if you suspect it as the cause. The mechanical pumps are relatively cheap last I checked.

If, however, you spent considerable time trying to start/pumping carb throttle (or any other reason you may have been pumping carb throttle), you may have just dumped too much fuel into the non-firing cylinders. In that case just change the oil and be done with it.
 
DC 340 said:
I would just replace it if you suspect it as the cause. The mechanical pumps are relatively cheap last I checked.

If, however, you spent considerable time trying to start/pumping carb throttle (or any other reason you may have been pumping carb throttle), you may have just dumped too much fuel into the non-firing cylinders. In that case just change the oil and be done with it.
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Not really a lot of pumping trying to start because I just pour a little splash of fuel in carb...fires right up. I'll try another pump, like you say, not too expensive to confirm or eliminate that as an issue.
 
nodemon said:
It's a new pump, not that new things can't be defective. Is there anyway to "check" it..?
Click to expand...
For starters remove it and examine. You can likely tell that fuel has been "cleaning" the area around the mount on the engine side. Most pumps have a bleed hole. Look for evidence there. Also, you should be able to "rig" it and pressurize it if you have a few extra fittings. 10psi should tell the story
 
So, all you've done with the car is idle and run it in place and driving it very little and you're wondering why the oil smells like gas. Yeah. do like all these experts say and tear into it. You already don't know which end is up from lack of diagnosis and you want to add to the pile. Good luck with that.
 
nodemon said:
Not really a lot of pumping trying to start because I just pour a little splash of fuel in carb...fires right up. I'll try another pump, like you say, not too expensive to confirm or eliminate that as an issue
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I’ve got a vacuum gauge/fuel pressure tester that utilizes a T fitting that temporarily plumbs into the fuel line. You should be able to find the same thing at any parts store. I’d recommend checking your fuel pressure before you go to the expense and trouble of replacing a fuel pump that might be operating correctly. It’s possible that the diaphragm on the fuel pump can be torn and leaking fuel into your crank case. Your fuel pressure would read abnormally low. You should have 4 to 6 psi for a stock, mechanical fuel pump.
 
ProjectBazza said:
Well it's a good thing we don't get snow here! (Or at least not this year, at any rate....) :rolleyes:

I wasn't aware that could be an issue, and it's good info to have. Thank you!
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Totally agree. That much gas in your oil is a problem that needs to be fixed.
 
middleagecrisis said:
I’ve got a vacuum gauge/fuel pressure tester that utilizes a T fitting that temporarily plumbs into the fuel line. You should be able to find the same thing at any parts store. I’d recommend checking your fuel pressure before you go to the expense and trouble of replacing a fuel pump that might be operating correctly. It’s possible that the diaphragm on the fuel pump can be torn and leaking fuel into your crank case. Your fuel pressure would read abnormally low. You should have 4 to 6 psi for a stock, mechanical fuel pump.
Click to expand...
Fuel pumps do not magically start putting out high pressure. Many do not know that the cam does NOT develop the pressure. The cam sorta "cocks" the pump on the vacuum stroke and the SPRING in the pump is what pumps the fuel and develops and controls the pressure. In fact, when the float closes on and off as you cruise, the cam sorta "floats" on the pump arm for a few seconds.
 
middleagecrisis said:
I’ve got a vacuum gauge/fuel pressure tester that utilizes a T fitting that temporarily plumbs into the fuel line. You should be able to find the same thing at any parts store. I’d recommend checking your fuel pressure before you go to the expense and trouble of replacing a fuel pump that might be operating correctly. It’s possible that the diaphragm on the fuel pump can be torn and leaking fuel into your crank case. Your fuel pressure would read abnormally low. You should have 4 to 6 psi for a stock, mechanical fuel pump.
Click to expand...
Fuel pressure is at 6 psi.
 
Looks like you can scratch off a fuel pump causing your problems. My suggestions will try to minimize cash out outlay for you. I looked at your video of the motor running and it sounds like you’ve got a healthy cam in it. It looks to me like you have an intermittent miss at idle, which is most likely an electrical issue. I’ve been messing with the Edelbrock 1405 carburetor I have on my 318 and they are extremely fuel pressure sensitive. Six psi is what’s listed by Edelbrock as max fuel pressure (4-6), but all the information I have been reading while diagnosing my problem says that’s too much for the carburetor to handle. The first thing I would do is look at your float level and make sure it is at the recommended 3/4 inch setting and make sure that the tab which controls the needle and seat opening is set to max 1 inch float drop. You can look online and see how all of this is done. While you’re at it, look at some of the YouTube videos that discuss tuning the Edelbrock 1400 series carburetors, there’s a few good ones that really go into depth about fuel pressure requirements and tuning. I’d also change your oil if you’re concerned there’s fuel on it. After you verified that your float level and float level tabs are set correctly, you can look at your ignition system. With the motor warmed up, try spraying use a spray bottle to mist each header and see if the water evaporates off of it. My gut feel is the carburetor is dumping too much fuel into the engine and you might have an intermittent miss from your ignition system. Have you looked at your spark plugs to see if one or all of them are fuel fouled? All of these things can be done for free and we’ll go a long way towards troubleshooting your problem. Let me know how these checks turn out and I will try to help you figure this out as best I can.
 
The way it's running from the pic
And compression numbers makes me think and exhaust rocker or push rod failure
Would pull the vc and make sure all your valves are opening
 
middleagecrisis said:
Looks like you can scratch off a fuel pump causing your problems. My suggestions will try to minimize cash out outlay for you. I looked at your video of the motor running and it sounds like you’ve got a healthy cam in it. It looks to me like you have an intermittent miss at idle, which is most likely an electrical issue. I’ve been messing with the Edelbrock 1405 carburetor I have on my 318 and they are extremely fuel pressure sensitive. Six psi is what’s listed by Edelbrock as max fuel pressure (4-6), but all the information I have been reading while diagnosing my problem says that’s too much for the carburetor to handle. The first thing I would do is look at your float level and make sure it is at the recommended 3/4 inch setting and make sure that the tab which controls the needle and seat opening is set to max 1 inch float drop. You can look online and see how all of this is done. While you’re at it, look at some of the YouTube videos that discuss tuning the Edelbrock 1400 series carburetors, there’s a few good ones that really go into depth about fuel pressure requirements and tuning. I’d also change your oil if you’re concerned there’s fuel on it. After you verified that your float level and float level tabs are set correctly, you can look at your ignition system. With the motor warmed up, try spraying use a spray bottle to mist each header and see if the water evaporates off of it. My gut feel is the carburetor is dumping too much fuel into the engine and you might have an intermittent miss from your ignition system. Have you looked at your spark plugs to see if one or all of them are fuel fouled? All of these things can be done for free and we’ll go a long way towards troubleshooting your problem. Let me know how these checks turn out and I will try to help you figure this out as best I can.
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Thanks for the suggestions..! Will let you know how it works out..
 
nutz said:
The way it's running from the pic
And compression numbers makes me think and exhaust rocker or push rod failure
Would pull the vc and make sure all your valves are opening
Click to expand...
Will do.. Thanks..!
 
FIRST THING change the oil and filter before you run it. And yes the fuel pump can leak fuel into the engine oiling. It was never a major problem on Mopars but chevys had a lot of issues with them. Did you flood it trying to start it at one time? Does the chock work correctly? There are a number of issues that can cause this, but first change the oil. Even if you misdiagnosis it $25.00 is cheap insurance to ruin an engine. Even 25 x 2 is cheap.
 
My one friend had a 67 GTX and flooded it one cold Detroit morning and pulled the coil wire out and put it next to the valve cover to check for spark. He found it 3 houses away with all 6 holes slightly enlarged. He might even had sprayed ether in it? It could have killed him.
 
My only comment on this is. "if you smell gas, STOP what you are doing". Look for the source before turning on the key or any light switch in the shop. As many said here, change the oil first. If not for an explosion but for the dilution of the oil. Both are not good.
 
Just curious, did you check oil level on lipstick? Maybe if it's obviously high, definately a red flag. Not sure how long you've been tweaking it, or short run/stop cycles, or hard starting,...ect? Could be a combination of any/all of too much dumping gas down carb, too high pressure overcoming needle/seat, bad diaphragm, on top of old oil.

Start with basics! Fresh oil. Tune to where it starts without priming carb every time or cranking it forever.
 
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