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Discussion Starter #1
Hey Fellas,
I am getting a leak that puddles up at the front edge of my valley pan/on top of my waterpump. anyone have any ideas of what it could be? Could it be an issue with the Valley Pan/Gasket? (Pic added for reference, the leak is cleaned up but the area where the paint has been deteriorated is where the leak generally is)
140818


Thanks in advance,
V/r Jason
 

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not that it makes much difference but the studs belong in the holes reference in the picture, the upper holes near the water ports get a 3/8 x4 coarse thread bolt. the origin of the leak coolant?? maybe from the front intake runner
140824
 

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Hey Fellas,
I am getting a leak that puddles up at the front edge of my valley pan/on top of my waterpump. anyone have any ideas of what it could be? Could it be an issue with the Valley Pan/Gasket? (Pic added for reference, the leak is cleaned up but the area where the paint has been deteriorated is where the leak generally is) View attachment 140818

Thanks in advance,
V/r Jason

Oil or anti-freeze?
 

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Discussion Starter #4
Oil or anti-freeze?
Jim, I am almost 90 percet sure that its oil. Looking at the valley pan itself, there is oil residue going to front to back and i often have a smallish leak coming from the rear of the engine. It seems to only happen when it is at higher RPMs and when i take it for longer drives. If i just put around the negibhorhood it doenst seem to happen.
 

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Small leak in the rear, small leak there high RPM’s...I would suspect crankcase pressure is too high

Easy fix is a top functioning PCV system. That will clear out the pressure...and stop the leaks. Best one bar none is the ME Wagner dual flow PCV valve. Check their website for more info.

At any rate start with a good fresh unclogged and properly routed PCV, sit breathers alone will not work optimally.
 

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Jim, I am almost 90 percet sure that its oil. Looking at the valley pan itself, there is oil residue going to front to back and i often have a smallish leak coming from the rear of the engine. It seems to only happen when it is at higher RPMs and when i take it for longer drives. If i just put around the negibhorhood it doenst seem to happen.
OK, maybe from under the distributor? There is a gasket that is often found in rebuilding kits that goes around the distrib housing and seals between the distrib base and block. I would clean up the valley pan and then check back there after a good high speed blast or two. I can't say as I have always used these gaskets myself and most engines don't seem to have them, but it could be an area to look at since the oil is traveling from the rear forward.

No oil pressure gauge hook-up near the distributor? You can tap the gauge into the small oil passage next to the distributor instead of down at the oil filter housing. Some will use this location instead, so if your engine has the gauge tapped in here, look for a possible leak at the line or fitting.

Of course it could be other places such as a valve cover gasket seeping under pressure. Valley pan's typically don't leak, but they can. If the block was "zero decked" it can change the geometry dimensions of the block in that it would narrow the cylinders inward. What then ca happen is that the outer lip on the valley pan is now too wide and does not seat tight as it should. It may work for a while, but eventually give out and begin to seep.

Another problem is the 2-bolts that secure the valley pan can sometimes be over tightened ad pulling down on the center, and causing a sealing issue on the outer lip of the pan. There are small rubber/gasket seals that go under the heads of those 2 bolts. If left out, there could be oil being pushed out under pressure.

However, seeing you mentioned it only happens at high speed/RPM's, I am leaning towards too much internal engine pressure forcing oil out - especially as the engine gets old and blow-by increases. This can be a common problem with these engines IF you don't have breathers or functioning PCV valve system on the engine. - Lemans guy beat me to it, so read his post suggestions.
 

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PJ has the more detailed analysis, and agree totally. Often those distributor gaskets are missing or destroyed. Good news is you may have some easy fixes...
 

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Discussion Starter #8
Hey fellas,
So after clean all of the old residual oil off and watch things that the motor was on and reving it, and it looks like it is coming from the driver side of the top area where the timing cover/waterpump meets the block. I made sure all the bolts were sung and its still leaking, only comes out when it is reving and the RPMs are increased moving from the driver side to the passenger side as a reference. Any ideas on a quicker fix before i go out and get a new timing cover?

Thanks guys.

Jason
140844
 

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I would fix the PCV system, upgrade to ME Wagner before tearing off the water pump and timing cover etc. Because if your issue is too much crankcase pressure, all your new parts won’t help the gaskets will still leak from the pressure.

Now if that does not fix it, then I would go for the timing cover replacement job.

But your photos it looks pretty clean, so it sounds like seepage and not a full on leak if it is a full on leak you will have to replace the gaskets and should do whatever you need to then new timing cover, after pump etc.

Much easier to do an ME Wagner valve dial it in for your combo, very easy and see what happens. It is money well spent even if it does not fix the leak, and then you can replace what you need too.
 

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Discussion Starter #10
I would fix the PCV system, upgrade to ME Wagner before tearing off the water pump and timing cover etc. Because if your issue is too much crankcase pressure, all your new parts won’t help the gaskets will still leak from the pressure.

Now if that does not fix it, then I would go for the timing cover replacement job.

But your photos it looks pretty clean, so it sounds like seepage and not a full on leak if it is a full on leak you will have to replace the gaskets and should do whatever you need to then new timing cover, after pump etc.

Much easier to do an ME Wagner valve dial it in for your combo, very easy and see what happens. It is money well spent even if it does not fix the leak, and then you can replace what you need too.
[/QUOTEthanks, ill try the ME Wagnervalve. It looks clean because i cleaned off right before i took the pic. When i would rev it, you can see the oil bubble upthe cavity on the passenger side fills up pretty quickly.
 

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All the gaskets are under constant crankcase pressure, once that pressure has a good PCV system the gaskets are not under that constant pressure and work as designed. Now it could still be a leak that is not caused by crankcase pressure,...but starting there would be a good plan.
 
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