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Discussion Starter · #1 ·
My BBC leaks way too much oil! Every time I run it I get oil spray all over the back of the motor and bilge within a few mins. Its a huge mess.

It looks like its coming from between the head and block on the driver side rear of the motor. The heads are torqued properly and no water in the oil.
Is that common to be leaking from the head gasket?

Its not coming from the pan, rear mainseal or valve covers. I dont think its coming from under the manifold but its hard to tell because there is so much oil sprayed all over the place. From the looks of it, it just seems to be leaking from all around the rear of the head gaskets on the drivers side.

Im wondering if I should try to just replace the manifold gaskets or go ahead and do the head gaskets at the same time?

Thanks
 

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Oil leak

My BBF does the same thing. I was told that it is coming from my valve cover breathers. Is yours doing the same ? Last time out so much oil it fouled my bilge pump. My fix is going to replace breathers with new vented with a line to carb to burn off leaking oil. I am very new to this so a frind is going to direct me as to what to do, no exp. so I will give it a try and see if it clears up my problem....I do need a new bilge pump as well
 

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could be breathers but more thatn likely id say it was your manifold. are you using gaskets on the front and rear? if so, ditch em and run about a quarter inch of black high temp rtv insted of using gaskets. never heard of oil leaking from a head gasket. id venture to say if it was that severly blown youd have water in the oil unless its blown in just the right spot.
 

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could be breathers but more thatn likely id say it was your manifold. are you using gaskets on the front and rear? if so, ditch em and run about a quarter inch of black high temp rtv insted of using gaskets. never heard of oil leaking from a head gasket. id venture to say if it was that severly blown youd have water in the oil unless its blown in just the right spot.

X2 Ditch the gaskets.(front and rear only) Make sure you clean up surface of the block and manifold REAL good. Brake parts cleaner works well for me.:)devil
 

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if your gonna pull the manifold its really not that much more work to pull the head except for having to run the valves again. like i said, imo i highly boubt its your head gasket. do a leak down and if everything checks out on that id say pull the manifold and re-seal it,. dont forget to replace the manifold to head gaskets as well. throw er back together and get er back on the water!!!:)devil
 

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I'm No Expert
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Just so you know, these guys are NOT saying ditch your intake manifold gaskets and replace them with RTV. They are talking about the gasket on the horizonal rail that goes between the block (not HEAD) and manifold. drag your finger around the block in that area and see if there's oil, if it's that high then thats probably where your leaking.
 

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Discussion Starter · #11 · (Edited)
Yeah there are no cork gaskets used Just Silicone sealing off both ends. I Think I might just go ahead and try to replace those first. Only about four trips on these gaskets and silicone job.

Not coming from the breathers either. I have been trying to track this leak down and it looks like its coming from between the head and block on the #7 Cylinder.

I should probably disconnect the driveline and run her on the hose in the garage for a while to see if I can find the leak first.

This is a fresh motor.

I realize its kind of hard to find a leak just from my description in this post. Im wondering if it is really uncommon to have a head gasket leak? If so I would lean towards the manifold leaking more and not worry about the head gaskets.
 

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Yeah there are no cork gaskets used Just Silicone sealing off both ends. I Think I might just go ahead and try to replace those first. Only about four trips on these gaskets and silicone job.

Not coming from the breathers either. I have been trying to track this leak down and it looks like its coming from between the head and block on the #7 Cylinder.

I should probably disconnect the driveline and run her on the hose in the garage for a while to see if I can find the leak first.

This is a fresh motor.

I realize its kind of hard to find a leak just from my description in this post. Im wondering if it is really uncommon to have a head gasket leak? If so I would lean towards the manifold leaking more and not worry about the head gaskets.
a leak down test will tell you if your head gasket is blown 9 times outta 10
 

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Alright I'll admitt I'm a tool junkie But , good money spent here is for and IR lite and florescent dye test kit Just had an illusive oil leak and this device "nailed it" In this case it was the cam plug (needed to be "pressurized") It should tell you exactly where and how the oil is "getting out" ! Tom
 

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Simply an outside observation if you are not evacuating crankcase pressure in one way or another, you will have leaks somewhere for sure. We've remedied an awful lot of them over the years by only addressing crankcase vacuum.

If this is a pressure fed gallery leak, you'll have to hunt it down and fix it. The aforementioned remedy will do nothing for that.
 

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could be breathers but more thatn likely id say it was your manifold. are you using gaskets on the front and rear? if so, ditch em and run about a quarter inch of black high temp rtv insted of using gaskets. never heard of oil leaking from a head gasket. id venture to say if it was that severly blown youd have water in the oil unless its blown in just the right spot.
My aftermarket manifold expressly said NOT to run the end gaskets, but to RTV it in there.

I did, no problems, at all.
 

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Frank I had a leak in the same spot your typing about. It was my Oil Pressure gauge connection to the block. I didn't put any teflon tape on it and it was leaking pretty good. It was tight but not tight enough. The Spot I'm speaking of is right above the Oil Filter. There is either a plug or your sending unit if its electric. Jus sayin it might be the location. Hope its that easy
 

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Alright I'll admitt I'm a tool junkie But , good money spent here is for and IR lite and florescent dye test kit Just had an illusive oil leak and this device "nailed it" In this case it was the cam plug (needed to be "pressurized") It should tell you exactly where and how the oil is "getting out" ! Tom
that sh!it is cool as hell!!! do you have to add die to the oil before priming?
 

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that sh!it is cool as hell!!! do you have to add die to the oil before priming?
Oldsquirt is correct just surprized me it took me this long to step up , I use it in my other business as well, and now little Cheapy versions of this set up are available at CSK o'rielys etc , makes diag on stuff like this much more susinct Oldsquirt remember the Old school "beastly" special tool UV lamps that took a "warm up" period Tom
 
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