Fuel System: Gas in the oil AGAIN!

[rusty65]

'65 Daytona with a 283. I changed the oil several weeks ago and the old oil came out of the pan like it was pee! It smelled like raw gas for sure. I had changed out the fuel pump several months before for this very reason.This car doesn't get run often, maybe once or twice a month.Thought I'd change the oil just for the heck of it,now I find this.What gives?

[tsenecal]

Sounds like it must be the fuel pump (again). You would have to have a bad flooding problem, and loose rings to get that much fuel down through the cylinders. I'm sure that you are already aware that running oil diluted with gasoline will ruin the bearings, so I wouldn't run it any longer until it is figured out. There is also the chance of an explosion in the pan, causing damage. Better look for a better quality pump for the redo.

[Buzzard]

I had the same problem with my Weasel. When using an electric fuel pump ALWAYS use a pressure regulator to dial it down to about 3.5 lbs as those early carburetors' needle and seat can't deal with the higher pressure.

[rusty65]

Sounds like it must be the fuel pump (again). You would have to have a bad flooding problem, and loose rings to get that much fuel down through the cylinders. I'm sure that you are already aware that running oil diluted with gasoline will ruin the bearings, so I wouldn't run it any longer until it is figured out. There is also the chance of an explosion in the pan, causing damage. Better look for a better quality pump for the redo.

Copy that.

[NCDave51]

Several low-P pumps out there as well.

https://www.pegasusautoracing.com/productdetails.asp?RecID=2698

My 59 Lark VI is running a 2-4 psig Mr. Gasket pump for example, having removed the old fuel pump for the same risk/reason as yours.

[swvalcon]

I've owned a ton of small block chevs and driven them for thousands of miles and never had one that couldn't be fixed with this problem. Buy a good grade pump and not the cheapest China made junk available.

[Jeffry Cassel]

Bet you have a nice clean motor. I have a crappy UV that I ran for a couple years on farm tank gas which, the state says must be ethanol. Gas would find its way into the crankcase of the china made Subaru "Made in the USA" motor. I'm not sure if I'm glad it didn't burn up or disappointed it didn't. I switched it to no alcohol gas and it stopped doing, hasn't done it since, and I don't know why. Almost has to be hole in diaphragm of fuel pump. I think I've been running about 50% on replacement parts (half are defective) Its fun to fix things but not when you have to do the same repair 2 or 3 times.

[NCDave51]

I've owned a ton of small block chevs and driven them for thousands of miles and never had one that couldn't be fixed with this problem. Buy a good grade pump and not the cheapest China made junk available.

I hear you - but even my 100% original pump would have to be rebuilt with a kit that I can’t guarantee will be up to the task - made here or abroad - and survive months of storage against likely ethanol-containing fuel. That’s all.

[55s]

Neoprene ( the rubber that used to be used for all hoses and fuel pump gaskets and carburetor needle seats about 20 years ago) does not like ethanol. It dissolves and leaks and creates a tar like substance that coats everything, usually showing up in the carburetor.

New carburetor kits, fuel pump gaskets, hoses and anything that touches gas that has ethanol must be replaced if they are made with neoprene and ethanol gas is used. The substitute rubber is typically Nitrile rubber.

[NCDave51]

Agreed, or even EPDM perhaps?

Do you or other folks know then if the current “studebaker vendors” offer ethanol-friendly rebuild kits? Would be a good thing going forward.

[StudeRich]

Some do, but Then and Now Automotive Classic Auto Parts make and sell them.

https://www.then-now-auto.com/fuel-pump-repair-kits/

[StudeRich]

'65 Daytona with a 283. I changed the oil several weeks ago and the old oil came out of the pan like it was pee! It smelled like raw gas for sure. I had changed out the fuel pump several months before for this very reason.This car doesn't get run often, maybe once or twice a month.Thought I'd change the oil just for the heck of it,now I find this.What gives?

Your issue with your Canadian Pontiac 283 makes be wonder if you actually GOT the correct Mechanical Fuel Pump for a Studebaker.

People have said that the one Studebaker of Canada used, was a somewhat rare Chev. Truck Pump for Engine Mount Clearance and not your Standard '64 Chevelle 283, Auto Parts Store special.

[rusty65]

Thanks for the comments so far,gents. The first fuel pump I installed was an Airtex unit, which was a POS China waste of money. The more recent install (looking back, it was several years ago, not several months ago as previously stated) was a Carter unit IIRC.Can't find the receipt for that one. Looking back they were both a tight fit and a PITA to install. I don't want to go the electric pump route quite yet but I may after I get some other things done to the car. At this point the Daytona is a yard driver with the interior and wiring stripped out of it.

[Rhys]

Rust65


JEGGS makes a mechanical Fuel Pump # 15952 that fits. You can index the bottom of the pump, if needed, to align the inlet/outlet ports.

The cost was $46 for the Black Pump. Some folks have suggested using the Holley Fuel Pump, but it is double the price and not suitable for Ethanol Fuels.

The install was easy. I was able to use the original 1/8" fittings, but had to find (2) reducer bushings because the pump inlet/outlet are 1/4"

Save the the old fuel pump and have it rebuilt. But for $46 - this works.


Rhys

[rusty65]

Thanks, Rhys! I was planning to look at Jeg's and Speedway websites today.