Oil pan/babbiting question

[Bob from Northport]

We just received a 28 Roadster truck into the shop. Owner complaining the engine seized up suddenly. Truck started very easily, but when we drained the oil pan, it had about 2 gallons of gasoline or more in it. It was running out the back of the oil pan there was so much in the pan. Truck has a B engine, Schofield head with 2 down flow carburetors. Also an electric fuel pump-pressure checked to 2.7 lbs.

1. What damage will the gas do to the babbiting??
2. Anyone hazard a guess as to the possible problem??

Thanks!!

[Tom Wesenberg]

Does the electric pump push the gas through the mechanical pump? If so, the diaphram may be bad and leaked a lot of fuel into the oil. It pays to check the oil often.

If the engine locked up expect to find serious babbit damage.

[Bill in SoCal]

My guess is that gas is draining down the intake manifold and past the cylinder rings when the engine is turned off. Bad float valve or too much pressure from the pump. Does the pump start pumping when the ignition is on before starting the engine? If it does stop pumping - will it start again in a few minutes with the engine still off?

Gas washes the oil of the cylinder walls and thins the oil which will cause more than normal wear on all the engine parts. The more gas the more wear. Bill

[PC/SR]

1. Gas will not damage babbitt so long as the engine is not running. Gas will not bother babbitt. However oil is necessary if the engine is running.
2. The first obvious problem is too much raw gas. What kind of carbs? Check the carb float level first thing. Are you using the B mechanical pump plus an electric pump? Just a wild guess, does the electrical pump turn off when the key turns off?
Edit: Agree with Bill.

[Synchro909]

If the excess fuel is coming from the carburettor, I'd be concerned for the condition of the bores too. I've seen engines ruined by fuel washing the oil off the cylinder walls, as described above.

[Tom Wesenberg]

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The way it was stated, I thought the engine seized while driving, but now see it could have hydrolocked. If it hydrolocked then the babbit should be OK, but you'd better check the cylinders for wear or damage.

[pooch]

Who started the engine after it came in ?

[Mitch//pa]

Originally Posted by pooch

Who started the engine after it came in ?

i was wondering also why it was started with the crankcase full of gas.
no doubt you have a fuel delivery issue, which should be pretty easy to figure out

[Bob from Northport]

To answer some questions- the owner started the truck coming out of his trailer- when we told him to shut it off. We see no damage to the head or cylinders. The owner was NOT shutting off the gas under the tank like we advised. With a full tank in the truck, he said it would disappear over night to a half a tank. We discovered the fuel flow when we disconnect the fuel lines from the carburetors.
The fuel pump does NOT come on with the ignition. There is a separate switch to turn the pump on an off. We will check the floats in each carb.

[100IH]

There have been several threads recently about fuel pressure regulators not able to reduce pressure low enough for downdraft carbs. Pump should be wired to run only with the ignition on. Is there a pressure regulator on the car? Check the pressure first and go from there after reading about the recommended regulators.

[Tom Wesenberg]

Originally Posted by Bob from Northport

We just received a 28 Roadster truck into the shop. Owner complaining the engine seized up suddenly. Truck started very easily, but when we drained the oil pan, it had about 2 gallons of gasoline or more in it. It was running out the back of the oil pan there was so much in the pan. Truck has a B engine, Schofield head with 2 down flow carburetors. Also an electric fuel pump-pressure checked to 2.7 lbs.

1. What damage will the gas do to the babbiting??
2. Anyone hazard a guess as to the possible problem??

Thanks!!

I'm still unsure what was meant by "seized", and I'd pull the head to make sure those 2 small water holes are blocked off. That would be the two holes near the center that need to be blocked when not using the original head and gasket with a B block.

[hardtimes]

Hey Bob,
If you take the head off, as suggested, to check to see if A block water holes were properly plugged (when using an aftermarket head/gasket on a B block).....actually there are FOUR such holes to have plugged, i.e.- 1/4" holes; one on each end of block and two toward center of block. The 'idea' with plugging, is too provide extra support for head gasket AND to help prevent water leakage.
BTW...guys using more than stock carburetor , like various downdraft carb configurations with electric fuel pumps, should have a working knowledge of what they are using and how such equipment works and probable problems encountered. You have encountered one of the worst scenarios in this case. It is possible that no damage was caused, which would be great. But, it would be prudent to drop the oil pan and check things out. Hey, believe it or not gas will clean stuff pretty good, although I would not recommend cleaning an engine in the car this way !
A major question to ask the 'owner' is....how much time was this engine run with a half tank of gas disappearing each night. If not much run time, IMO, things will clean up well after all is checked/adjusted.

I remember in old days, we 'cleaned' junk yard engines internally by running different stuff thru it .

[colin1928]

My concern is that if it hydro locked are the con rods straight ?
about electric fuel pumps most will allow fuel to flow through when switched off they are not a stop valve

[Brendan]

that's why I check my oil every time I start up, got a Webber on my A, also I shut off the fuel and let the carb run out of gas when i put it away in the garage

[CWPASADENA]

Float valve in one or both carburetors is not seating tightly. With a full tank, if the fuel is not shut off, the carb will overfill and fuel will leak down the throat and into a cylinder, down past the rings and into the pan.

I have seen two cases of this very same thing recently. One was with two Stromberg carbs and one was with a new Weber.

If the carbs are Stromberg's, they are notorious about the float valves not completely sealing and the carbs overfilling and running over.

This is one reason I have up-drafts on all of my Model A's.

Shutting off the fuel when the engine is not running will prevent this from happening.

Change the oil and if it runs and sounds OK, run it. Chances are it will be fine.

My experience and opinion,

Chris W.

[pooch]

Maybe tell the dude to fit an electric fuel shut off solenoid after the pump seeing he is too lazy to turn the gas tap off.

[Bob from Northport]

That is exactly what we are going to do!! Thank all of you for you comments!!