Inliners International Forums General Discussion Engines puddle of oil in the bottom of the intake

Question:
Can extended idling cause oil to puddle in the bottom of the intake?

Text:
Did a cooling system flush by slow bleed. idled the 194 for about 20 minutes in 5 minute segments.

Right after the cooling system flush, I was having some trouble with fuel leaks on a Re-man Rochester BV. the carb is freshly re-manufactured. so I pulled it off and took it back to National. I noticed a puddle of clean motor oil in the bottom of the plenum below the carb. I checked the PCV hose as a possible cause but it's dry. The head had a complete service about a year ago. this car is progressing in a restoration and is becoming more active. compression is 1) 140 2) 145 3) 145 4) 150 5) 142 6) 142. any ideas? the engine seems to run fine.

Hi true blue . . .

The PCV is the most obvious path - the second avenue would be the valve guides. Are you running umbrella seals? Does the engine normally use oil?

A long bought of idling would have the intake in a high vacuum state so if oil is getting in then it could collect instead of being used up in combustion.

Personally I have never seen oil collect in an intake.

regards,
stock49

Are you absolutely sure it's oil?

When cold gas pools in the intakes. It can look oily if it mixes with soot.

Thanks for the replies.
Pretty sure the recent head work did include umbrella seals. the fluid in the intake was thick like oil. long idling before the head work produced a white cloud on rev. but this has stopped happening after the head work. even with the "oil" in the intake it does not smoke. I'll keep an eye on it. I found no oil in the PCV hose. I should've Q tipped it but it looked dry.

Also dealing with BV fuel leaks. seems like I'm using a lot of force on the inverted flare at the carb connection. the two halves look fine under a magnifying glass. Maybe I've forgotten how much force a flare connection requires. The line is reasonably square in the fitting.

Fuel lines should be DOUBLE flared! You are using steel lines, right??

Use the double flare like used on brake lines if you haven't already.

Oh come on! A little fuel leak right over 700 degree headers hasn't hurt anyone now has it?

It is a double flare. it's a reproduction OEM material (plain steel) pump to carb line from "fine lines", purchased from OPGI. right after I got the carb back I had trouble with the leaks. since the carb folks test run the customer's carb on a Ford six, I was suspicious perhaps the carb side of the connection might have been damaged during there testing/tuning, and since the new line from OPGI leaked equally bad as the perfectly good stainless line I just removed. I'm putting a fire extinguisher in the car. Just because it seems fixed does not mean it cant crack unexpectedly

thank you all for your help and concern. MUCH appreciated.

It DID wash all of the paint off of a couple of tubes on my 4banger!!