Oil Leak-What have I done?!

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equium

equium

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Back Story: 1970 Plymouth Valiant, 318. Recently Installed Edelbrock Performer intake and edelbrock 1406 Carb. Installed PCV from Left valve cover to PCV port on carb. Oil cap on right side valve cover. (Covers are Mr. Gasket chrome installed by PO).
I just put the finishing touches and got a decent tune on it (could be better).
I took it out on a shake down cruise to Autozone to show them what the hell I've been working on. On the way, I tested my kickdown adjustments and for the first time since I've owned it, it finally kicked down at WOT.
So I get to AZ and a gal there is doing a battery test since it was cranking a bit slow. I look under the car for the heck of it and I'm leaking oil from the rear of the engine. I don't have a dust cover for the transmission, and it's leaking from the low point at the bottom of the housing. (Dust cover install coming).
Thinking it was the rear main seal, I added some Bars leak rear main seal repair.
I know it could take a while for the additive to work (if it is my seal).
I'm thinking perhaps I blew a gasket when I went to WOT.
After a search, I found that both of my valve covers should breathe, so a few minutes ago, I replace the oil cap with an oil breather.
Looking for opinions. What have I done?
 
................its probably leaking from the back of the intake or valve covers................yes u should have a breather on the opposite side of the pcv valve........kim......
 
Danny, it's quite possible when you went to WOT, it caused a bit of pressure and forced the oil out of who knows where. It could be simply coming out around the valve covers and running down the back of the block.

Mechanical oil gauge? Is it leaking there?

PCV on one side, and a breather on the other will/should help.

On a side note, Bars leak is probably not the best solution.
 
Bad Sport said:
Danny, it's quite possible when you went to WOT, it caused a bit of pressure and forced the oil out of who knows where. It could be simply coming out around the valve covers and running down the back of the block.

Mechanical oil gauge? Is it leaking there?

PCV on one side, and a breather on the other will/should help.

On a side note, Bars leak is probably not the best solution.
Click to expand...

Thanks BadSport
Today was my son's first day to drive it to school since I bought it back in October. (lots of upgrades). I'll give it the "once over" when he gets home.
I have not installed a mechanical Oil Pressure gauge yet, so no leak there.
The Bars leak was an impulse buy. I have been schooled to never put that kind of stuff in my cooling system; was not sure about engine, though.
 
equium said:
The Bars leak was an impulse buy. I have been schooled to never put that kind of stuff in my cooling system; was not sure about engine, though.
Click to expand...

Yeah, it's just a band aid fix, best to find the real issue. Like I said, it could be as simple as too much pressure without the breather.

Clean it some, and take it for another blast or two and see if it still does it, it may not.
 
back of the intake is my guess also.
Did you leave the dowel pins in the runners and/or use the cork gaskets ?
 
RedFish said:
back of the intake is my guess also.
Did you leave the dowel pins in the runners and/or use the cork gaskets ?
Click to expand...
I'll check there. No dowel pins. Had to remove them for the edelbrock performer intake.
no cork gasket, they called for RTV only.
I'm really hoping it's a gasket and not the rear main seal. I like all these ideas and places to check. Thanks Redfish.
 
My mopar performance valve covers needed clearancing with the air gap intake. They were hitting just before snugging down and leaking down the back of the engine. Good luck.
 
If the seals weren't leakin before bars leak, they damn sure will now.
 
OK. preliminary inspection when my son got home from school. Looks like leaking is coming from near the distributor. Possibly from the RTV when I installed the intake. It was dirty near there the head meets the block, but i'm praying it's not the head gasket.
I sprayed some degreaser behind the engine and cleaned it up to get somewhat of a blank canvas. I'll keep an eye on it.
I'll keep you all informed. thanks for reading
 
I am thinking you created a leak with to much crankcase pressure, even though you have the pcv in one cover it was doing nothing because you had a cap on the other valve cover, basically you have a sealed motor, doesn't take much blowby to create pressure
 
torkflight said:
I am thinking you created a leak with to much crankcase pressure, even though you have the pcv in one cover it was doing nothing because you had a cap on the other valve cover, basically you have a sealed motor, doesn't take much blowby to create pressure
Click to expand...
What do you suppose would blow first? Head gasket or the RTV on the new intake.
The heads were installed less than a year ago, so the gaskets are still kinda new.
 
equium said:
What do you suppose would blow first? Head gasket or the RTV on the new intake.
The heads were installed less than a year ago, so the gaskets are still kinda new.
Click to expand...

I think it would push out the end of the intake, I have had them push out the corners of the oil pan also, the head gasket will only get pressure from compression and coolant, not so much crankcase pressure
 
torkflight said:
I think it would push out the end of the intake, I have had them push out the corners of the oil pan also, the head gasket will only get pressure from compression and coolant, not so much crankcase pressure
Click to expand...
Thanks for that. I feel better. Since posting, I've gone back and re-read the Edelbrock intake installation instructions to make sure I didn't miss anything. I've discovered that it called for a 1/4" high bead of RTV in place of the cork gaskets. I think I did a 1/4" wide; not quite the same. And to top it off, I forgot to continue the bead up the sides of the heads.
everything is pointing to my RTV bead. When my son started it this morning before school, I looked down behind the distributor and started to see oil. There's a small ridge in the block before it slopes down where it was pooling.
I'm already planning to replace the gaskets.
 
The oil sending unit is in close proximity to the rear of the intake and they are known for leaking. You need to do an oil change and get that crap *** bars leak out. It is good for nothing but swelling every rubber seal in the engine and ruining them. It is a quick temporary fix mostly for used car lots. It will do much more harm than good long term.
 
RustyRatRod said:
The oil sending unit is in close proximity to the rear of the intake and they are known for leaking. You need to do an oil change and get that crap *** bars leak out. It is good for nothing but swelling every rubber seal in the engine and ruining them. It is a quick temporary fix mostly for used car lots. It will do much more harm than good long term.
Click to expand...
I'll check the sender. I have an oil pressure gauge that I have not installed yet; this will be a good time to install it while I have all that room.
I'm receiving a new toy today (bendpak quick lift) and I'll make the oil change my first use of it.
 
1/3 taller than the gap is about what I go by on intakes with RTV.
I'll bet anything that is where the oil is coming from.
 
PCV = positive crankcase ventilation. If its hooked up it would attempt to pull a vacuum on the crankcase thus pulling air in through dipstick tube or wherever possible. That's why there is a breather with a filter element in it.
 
Clean up the area around where you put the rtv. Put some rtv on your finger, and lay another coat on pushing it into all the cracks an crevices. Especially where the head, block, and intake meet . let it set up . you probably didn't use enough when you installed the intake. If that doesn't work, then look at the sending unit.
 
I too had to clearance my aluminum valve covers for the AG.
-No, on the let skin question.Yes on the rub it in statement. Yes on the get it out advice.
-When I was a newbie, I would put that RTV on,drop the manifold on,then pull it back up and inspect the transfer. Caught a few potential leakers that way.Its not usually that messy. Also, if youve put too much on heres your chance to prevent it from migrating into who knows where.
-I have seen that Bars Leak swell rubber up pretty bad, including what I believe was RTV.When it (the rubber or RTV) swells it has enough power to relocate itself out of where its supposed to be.
-Also, remember that at WOT the PCV system works in reverse.Excess pressure is vented out the breather, and on factory systems, back into the air cleaner housing.So if you capped it.......It usually blows the dipstick out first,though.Blowby pressure can easily reach 2 to 4 psi, so yeah, it can blow anysoft parts out. They used to sell big orange airbags, to, in an emergency, lift your 3500 pound car, using the exhaust system pressure.The engine doesnt like 4 psi of backpressure at idle,and may stall soon therafter.They work well.
 
I've always used silicone ( and still do), something about that rtv. Room Temperature vulcanization !
 
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