A small oil leak.

[mikiec]

2 drops in 600 miles on a brand new motor. It's coming from the rear of the engine. Heres what has been done. Dye added to the oil to find the offending oil vessel spurting this precious commodity. Found a very small dab on the bottom of the back of the engine. It was suggested that the owner drive for awhile to let the dye circulate and then look for the offending area.

Owner removed the tranny, clutch, pressuer plate and flywheel. He found a small amount of dye oil in the area. He removed the 1 piece rear main seal from the crank and is concerned that the engine side of the seal is coated with dye. Wants to know if the seal is supposed to have oil in this area.

Mike

[vettestr]

Originally Posted by mikiec

2 drops in 600 miles on a brand new motor. It's coming from the rear of the engine. Heres what has been done. Dye added to the oil to find the offending oil vessel spurting this precious commodity. Found a very small dab on the bottom of the back of the engine. It was suggested that the owner drive for awhile to let the dye circulate and then look for the offending area.

Owner removed the tranny, clutch, pressure plate and flywheel. He found a small amount of dye oil in the area. He removed the 1 piece rear main seal from the crank and is concerned that the engine side of the seal is coated with dye. Wants to know if the seal is supposed to have oil in this area.

Mike

MikieC,
There ya go exaggerating again, the engine may have 600 miles but only took a couple 3 weeks to create the 2 drop puddle and maybe 25 or 35 miles of driving. She won't leak the puddle with less than 20 or so miles between the environmental exposures. 2 earlier puddles did not contain dye so is a sneaky kinda leak. There also seems to be visible dye on the crank where the seal rides on it????

[bobcowan]

That area of the seal is supposed to have oil on it.

Every oil leak on almost eny engine usually shows up on the front of the block plate. It's a nearly horizontal surface on the engine that is tilted towards the rear. Mot people assume it's the rear main seal, when it usually is not.

First, check the most obvious places first - valve cover, oil pan, etc. It could even be from the fuel pump boss or crank seal.

One weak spot on a SBF is the front cover to oil pan seal. Make sure those front 4 bolts are sealed with silicone or thread sealant. On some covers those bolt holes extend to the interior.

Clean the engine really well. Make sure everything is throroughly degreased. Let it sit for a day or two to make sure it really is dry. Sprinkle the suspect areas with baby powder or corn starch. Run the engine for a few minutes, and look for changes in the powder. You'll need a strong light and a mirror.

Or, a lot of shops have a leak detecter. It's a machine that produces a petroleum based smoke. They inject it into the engine via the valve cover or dip stick. Where the smoke leaks out is where the oil leaks out.

[patrickt]

Man, if this was an FE two drops wouldn't even have warranted a post.

[DWRAT]

No leak is a small leak to me.
A leak is a leak and whoever did all his work most not want a leak at all.
I personally would do the very same thing if my rear main was/is leaking.
Some of us don't like leaks and some of us are OK with leaks.

No different then a Cobra with a Chevy motor or a Chevy color, it's not to be there.
Dan

[Danr55]

Ford had some issues with small block motors during the 60's. Some of them leaked perpetually. I've had at least 3 289's that leaked either at the timing case or the back of the intake manifold or both. No amount of fussing or fixing could stay the seepage. I'm finding that the FE is much the same kind of dog. It leaks when It wants to leak. You can't stop it. You can't even find the source much of the time. You just learn to live with it.

[Robert McLinden]

As the radial engine boys say, "its not leaking, its just marking its territory".

[Excaliber]

Wouldn't the dye have a tendency to adhere to many different internal engine components, like the INSIDE of the real seal?

[patrickt]

Originally Posted by Excaliber

Wouldn't the dye have a tendency to adhere to many different internal engine components, like the INSIDE of the real seal?

As luck would have it, I'm using UV dye in the oil of one of my other non-Cobra cars as we speak. Last night I looked for the leak in the dark under a strong UV light, and couldn't find it. I took the cap off the oil filler tube and shined the light in there (thinking that maybe the old dye had lost its "glow") the inside of the tube, and everything I could see in there, lit up like a 60's rock stage. So the answer is "Yes, the dye will adhere to anything that has a film of oil on it."

[mikiec]

Damn good thing you don't own an older Harley.

Any excuse not to lose your rookie status. Works for me.

Mike

[BOURRET]

Originally Posted by patrickt

Man, if this was an FE two drops wouldn't even have warranted a post.

It is what I think.
But a leak cannot diseappear by itself, it can only increase.

[BPWilliams]

That is not a leak... there was no mention of a drip pan or oil absorbant...

I know that when mine stops leaking it is time to add fluids... when cars are driven properly they leak......

[DWRAT]

Originally Posted by mikiec

Damn good thing you don't own an older Harley.

Any excuse not to lose your rookie status. Works for me.

Mike

Neither of my Harley's ever leaked a drop or they would have been fixed also.
This was my baby.

It's just the right thing to do, fix all leaks.
Ask Danr, I belive he just paid big bucks to have his rear main replaced.

I passed on purchasing a couple Cobras because they leaked like pigs.

[patrickt]

If you've never used dye to find your leak, it's pretty hard to miss. Here's a shot a I took a few minutes ago shooting down in to the oil filler under the UV flashlight. I can't find my leak though, it quit leaking after I put the dye in.

[Car Nut]

Originally Posted by DWRAT

Neither of my Harley's ever leaked a drop or they would have been fixed also.
This was my baby.

It's just the right thing to do, fix all leaks.
Ask Danr, I belive he just paid big bucks to have his rear main replaced.

I passed on purchasing a couple Cobras because they leaked like pigs.

Harley's better leak unless they are a belt drive, no chain should ever be dry enough that they don't leave a drop or two.

I read somewhere that oil dye actually promotes leaks. It tends to break down the clinging properties of oil.

Really.

[elmariachi]

Originally Posted by patrickt

and everything I could see in there, lit up like a 60's rock stage. So the answer is "Yes, the dye will adhere to anything that has a film of oil on it."

I was looking for words to describe the dye illumination and this nails it.

I just ripped mine apart to correct the rear pan leak and to my heart's delight, no rear main leak. But to my surprise the dye helped me see that the middle side oiler galley plug was weeping a nice hidden stream down to the block edge and back above the pain lip and onto the block plate at the driver's corner. Its pretty amazing to see how much subtle weeping is going on with this FE engine after 2k miles.

[DWRAT]

Originally Posted by Car Nut

Harley's better leak unless they are a belt drive, no chain should ever be dry enough that they don't leave a drop or two.

I read somewhere that oil dye actually promotes leaks. It tends to break down the clinging properties of oil.

Really.

All my bikes have been belt drive.

[mikiec]

That is not a real Harley. Tire is bigger than my cobra.

Speaking of Cobras.. Done yet? We have a run tomorrow the 1st.

Mike

[vettestr]

I heard a rumor that Capt. Valdez installed a new rear main seal yesterday in his rockin rookie ride. The FelPro seal was replaced with a Ford Racing piece so if it leaks this time it will be with more correctness anyway.

I think it will be a while till we know if this worked or not cause it took awhile to show up before but I am pulling for Rookie success on this one. Don't tell him but I hate leaks too. I would have given it a few heat cycles or maybe a couple hundred miles to either stop or leak enough dye to be sure what is drippin but what the hell he did the work.

PS..... Dan, don't take any more things apart. Drive it!

[mikiec]

If it does not work this time, I'll swat my non leaking motor for his.

Mike
PS I hate leaks also.