HELP = Strong Gasoline Smell on Oil Dipstick ??????

RTR · Apr 2, 2011

Next issue with the little Cub tractor is when I pulled the dipstick to check the engine oil, I noticed it seemed a little "thin" and runny. Almost immediately I could smell gasoline. Apparently it is mixing in with the engine oil. What would be the cause for this to happen, and what would be the solution to fix the problem. What about Troubleshooting??

Here is what I know so far:

* The tractor spins a little longer than normal before it "fires".
* Once it fires like it wants to run, it takes a little bit of choke to get it going from initial "fire".
* After the tractor sits and runs for approximately 2 minutes (without choke) at half throttle, it suddenly wants to die. If you "play with" the choke; the engine will stay running.

All of those signs tell me it must be something wrong with the carburetor and it probably woudln't hurt for a rebuild of the carburetor. The hood is off the tractor, therefore the tank/sediment bowl possibility can be ruled out. I am just letting you all know its doing this in case it has something to do with the Gasoiline getting into the Engine Oil.

THANKS FOR ALL OF YOUR HELP. I LOOK FORWARD TO HEARING FROM EVERYONE!

Jim350 · Apr 2, 2011

We had a Massey on a job that had gas in the oil and in this case it was worn out piston rings.

I would do a compression check.
Send me am email for the correct way to do a compression test.

RTR · Apr 2, 2011

We are actually gonna do a compression test tomorrow. If you wish to email me your instructions, you may send it to [email protected].

The owner did tell me that the engine was rebuild several years ago. It seems to run fine as far as being powerful and it has no smoke or blowby at all. I did hear a slight knock towards the front of the engine though. Aside, it runs strong and smooth with no type of smoke at all.....

evilboweivel · Apr 3, 2011

look here
poke here

sflem849 · Apr 3, 2011

The float sticking will cause it to fill the crankcase with gas. It is always a good idea to turn the gas off when you let your tractor sit.

gene bender · Apr 3, 2011

How is the gas from the carb on a Cub get up thru the carb into the crankase.

Tom Fleming · Apr 3, 2011

The only way I know on a cub for gas to get into the crankcase is to be running REALLY rich, and then it is a stretch. It would have to sucking raw gas into the combustion chambers, and in that case, I would expect black smoke or fouled plugs coated with carbon.

something doesn't sound right......I hear what you are saying, but it is hard to make it add up........

sflem849 · Apr 3, 2011

(quoted from post at 05:53:34 04/03/11) How is the gas from the carb on a Cub get up thru the carb into the crankase.

Correct, it won't work on a Cub.

Tom Fleming · Apr 3, 2011

also, a valve out of adjustment can make a racket. I am not saying you don't have a knock, but a loud valve train can be misleading.

horsepoor · Apr 4, 2011

(quoted from post at 04:23:23 04/03/11) Next issue with the little Cub tractor is when I pulled the dipstick to check the engine oil, I noticed it seemed a little "thin" and runny. Almost immediately I could smell gasoline. Apparently it is mixing in with the engine oil. What would be the cause for this to happen, and what would be the solution to fix the problem. What about Troubleshooting??

Here is what I know so far:

* The tractor spins a little longer than normal before it "fires".
* Once it fires like it wants to run, it takes a little bit of choke to get it going from initial "fire".
* After the tractor sits and runs for approximately 2 minutes (without choke) at half throttle, it suddenly wants to die. If you "play with" the choke; the engine will stay running.

All of those signs tell me it must be something wrong with the carburetor and it probably woudln't hurt for a rebuild of the carburetor. The hood is off the tractor, therefore the tank/sediment bowl possibility can be ruled out. I am just letting you all know its doing this in case it has something to do with the Gasoiline getting into the Engine Oil.

THANKS FOR ALL OF YOUR HELP. I LOOK FORWARD TO HEARING FROM EVERYONE!

If you don't shut off the fuel bowl, and your float is wore out, gravity will work on a farmall cub just like the bigguns. This ain't a cadet, right?

mkirsch · Apr 4, 2011

(quoted from post at 05:30:44 04/03/11) The float sticking will cause it to fill the crankcase with gas. It is always a good idea to turn the gas off when you let your tractor sit.

It is practically impossible for the crankcase to fill with gas from a stuck float.

First off, the carb is an UPDRAFT. It is positioned BELOW the intake manifold.

The carburetor and the manifold would have to completely fill with gasoline before any started running into the cylinder. If that were the case, it would be so flooded that it would never start. It would hydrolock on the first crank over.

Second off, there is a drain on the carburetor that lets the gas run on the ground if the carburetor floods. That would have to be plugged before the gas would start filling the manifold.

Third off, the air intake isn't always a perfect seal. Gas would run out around the hoses even if the carburetor drain is plugged.

sflem849 · Apr 4, 2011

(quoted from post at 05:44:33 04/04/11)

(quoted from post at 05:30:44 04/03/11) The float sticking will cause it to fill the crankcase with gas. It is always a good idea to turn the gas off when you let your tractor sit.

Click to expand...

It is practically impossible for the crankcase to fill with gas from a stuck float.

First off, the carb is an UPDRAFT. It is positioned BELOW the intake manifold.

The carburetor and the manifold would have to completely fill with gasoline before any started running into the cylinder. If that were the case, it would be so flooded that it would never start. It would hydrolock on the first crank over.

Second off, there is a drain on the carburetor that lets the gas run on the ground if the carburetor floods. That would have to be plugged before the gas would start filling the manifold.

Third off, the air intake isn't always a perfect seal. Gas would run out around the hoses even if the carburetor drain is plugged.

But it could happen...I agree though. As I got to thinking, it probably wouldn't happen. Your tank would have to be plumb full and a bunch of other stuff. I was pulling off prior experiece with small engines. There it is a lot easier to have happen.

horsepoor · Apr 13, 2011

(quoted from post at 13:47:57 04/04/11)

(quoted from post at 05:44:33 04/04/11)

(quoted from post at 05:30:44 04/03/11) The float sticking will cause it to fill the crankcase with gas. It is always a good idea to turn the gas off when you let your tractor sit.

Click to expand...

It is practically impossible for the crankcase to fill with gas from a stuck float.

First off, the carb is an UPDRAFT. It is positioned BELOW the intake manifold.

The carburetor and the manifold would have to completely fill with gasoline before any started running into the cylinder. If that were the case, it would be so flooded that it would never start. It would hydrolock on the first crank over.

Second off, there is a drain on the carburetor that lets the gas run on the ground if the carburetor floods. That would have to be plugged before the gas would start filling the manifold.

Third off, the air intake isn't always a perfect seal. Gas would run out around the hoses even if the carburetor drain is plugged.

Click to expand...

But it could happen...I agree though. As I got to thinking, it probably wouldn't happen. Your tank would have to be plumb full and a bunch of other stuff. I was pulling off prior experiece with small engines. There it is a lot easier to have happen.

Farmall Cub fuel capacity = 7.5 gallons
1 gallon of gasoline weighs 6.073 lbs

45.5 lbs of liquid weight ABOVE the carburetor, yeah it won't push thru a stuck float and 60 year old rings. Look at what he is saying the problems are.
1.) "Tractor spins longer than normal before it fires. " I would thing the plugs are wet.
2.) "Once it fires like it wants to run, it takes a little bit of choke to get it going from initial fire." Choke helps weak sparkies, that might be trying to burn off gas.
3.)"After the tractor sits and runs for approximately 2 minutes (without choke) at half throttle, it suddenly wants to die. If you play with it, the choke, the engine will stay running." Might be due to a stronger spark since you're burning excess gas.

I would look at the carburetor, and rebuild it. Completly clean all the passages. If it is a stuck float, that would explain alot of this. 45 lbs of downpressure would push UP thru the manifold. GRAVITY WORKS!

-Horsepoor

mkirsch · Apr 13, 2011

(quoted from post at 05:38:37 04/13/11)
Farmall Cub fuel capacity = 7.5 gallons
1 gallon of gasoline weighs 6.073 lbs

45.5 lbs of liquid weight ABOVE the carburetor, yeah it won't push thru a stuck float and 60 year old rings.

How's the gas going to get from the carburetor into the cylinders?

The carburetor is BELOW the manifold, and has a DRAIN that almost always works.

999,999 times out of 1,000,000, you'll have a puddle of gas on the ground under the tractor, not gas in the oil.

horsepoor · Apr 13, 2011

I could be wrong. How is gas getting into the oilpan? To check for this, I would let it sit. Disconnect your air breather hose on the carb, before you try starting it and see if gas pours out here. If it doesn't then it is not leaking by.

-Horsepoor

HELP = Strong Gasoline Smell on Oil Dipstick ??????

RTR

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Jim350

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RTR

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evilboweivel

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sflem849

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gene bender

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Tom Fleming

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sflem849

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Tom Fleming

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horsepoor

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mkirsch

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sflem849

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horsepoor

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mkirsch

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horsepoor

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