leaky heads gaskets, I'm losing it!

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I will update my findings when I get back to the motor. I had to go back to work to get some rest. I'm sure some of you know what I'm talking about. :lol:
 
pishta said:
a brass wire wheel is much softer than cast iron. On Aluminum is a no-no. Get a piece of thick glass or a granite floor tile and glue a piece of 600 grit on its shiny face, nice and flat. Run this over the gasket plane a few times nice and easy and see if any area is getting missed, there is your low spot.
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True, it's softer, but ape hands like mine still dig trenches in iron with them. It's less likely to happen, but it can definitely still happen. A low force scraping with lots of repetitions can be an amazing force.
 
volaredon said:
too much oil? the excess will run off, if way too much will scrape itself off as you drop the bolt in the hole.
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The only symptom I've had with too much oil is having to retorque after a few hours. The oil will hydraulic at the bottom of the hole to some extent, but the threads never seal perfectly unless they're wrapped with Teflon or something equally dumb..
After an hour or so, the oil has seeped out and the proper torque can be achieved.
 
New info everyone. Not sure if this is my problem or not. I picked up a good used 360 magnum motor this week. I measured the thickness of the heads at the corners that are machined with the mounting surfaces. The set of heads I am trying to use is .025 thinner than stock heads. Looks like they have been resurfaced before I had them done again. How much can you take off of these things before you start having problems?
 
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Dana67Dart said:
Easy enough to check, put the gasket on the head, line up the bolt holes check all the passages.

Use the same gasket on the block do the same thing.

If all the holes are correct it's probably not the gasket.

Maybe you have a crack in the block that opens when the bolts are tightened?

Don't some of the head bolts penatrate the water jacket and need propper thread sealer to seal?

Could it be coming from the intake?

Are you giving any sealer a day or more to setup before putting fluids in?
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Buick V6 engines are a pain in the pisser. They changed the deck surface/cooling a few times. Head gaskets and heads have to be compatible with the block. Then one year they changed from odd fire to even fire and then a few months different they changed how the distributor drive and timing gear were installed. On one the distributor gear was machined on the front of the cam. On the other it bolted on. The cam has to match the crankshaft and that requires the matching timing set. A friend built a 3.8 for his 32 Ford. They could never get it to run right. He got a camshaft from a swap meet. I have a couple of books. One on just the Buick V6 and the other looks at a number of V6 engines. This is how they figured out the crankshaft/camshaft mismatch.
Before assembly when changing parts like heads, put the gasket on the block and on the head checking for any mismatch. It does not take much.
 
737jetdr said:
New info everyone. Not sure if this is my problem or not. I picked up a good used 360 magnum motor this week. I measured the thickness of the heads at the corners that are machined with the mounting surfaces. The set of heads I am trying to use is .025 thinner than stock heads. Looks like they have been resurfaced before I had them done again. How much can you take off of these things before you start having problems?
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My ported X heads have been decked at lest once that I know of. It took around .010 to clean them up.
My La block has been squared and decked, not sure how much was removed.
I just reassembled this engine with a new untouched AirGap intake.
No issues - no leaks
I do know that many builders correct the intake to make them work after decking heads.
Have you ever just half assed assembled the top end without gaskets to inspect the gaps between machined surfaces?
 
737jetdr said:
Unfortunately it doesnt run off. Excess oil rolls up the threads as you turn the bolts in, comes out the top and contaminates the clean head surface and ruins head gaskets. I like how there are pictures on line and in books showing people dipping their bolts in a cup of motor oil. Just enough to coat the threads is all I do.
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So, did you get the leak repaired or find the problem?
 
Just put a tablespoon of ginger powder from your wife's spice section in the kitchen cabinet and drive it.
 
pishta said:
a brass wire wheel is much softer than cast iron. On Aluminum is a no-no. Get a piece of thick glass or a granite floor tile and glue a piece of 600 grit on its shiny face, nice and flat. Run this over the gasket plane a few times nice and easy and see if any area is getting missed, there is your low spot.
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The success of an wire wheel on IRON deck surfaces, only if it's not razor scrapeable , is based mostly on the operator.
I can graze a IRON head with wheel and change nothing in regards to flatness.
It will destroy an ALUMINUM deck of course.

SIDE NOTE-Most people dont even need to mill their heads half as frequently as they do..
No one checks.. they just mill like it's a sbc with raised blhead bolt holes.
Sbc is crap, thin sliced crap.
 
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Correct me if I'm wrong here, but you initially said you were putting magnum heads on your LA block- and they have wet holes (no smart *** comments LOL) so I'd apply some thread sealant to the head bolts this time around and see if that doesn't solve the mystery? What have you got to lose? SFA!
 
It is an LA block but has blind holes. Nothing in the water jackets. I've been busy with yard projects as always seems to happen in May. Plan on getting back to my motor next week.
 
Just because the holes are blind doesn’t mean there isn’t water there. A little rust and BOOM, water.
 
737jetdr said:
I've got an La 318 and 2 LA 360s and 3 360 magnums. None go in the water jackets.
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I've got 3 that do.
Let me be clear ...its the 80's-90's that the head bolts went into water.

This is off an '84 318 roller.
Also note the higher torque rating than older 318's. 95ft lbs was for 340/360 before.

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and the unspoken truth is, if some do and some don’t. It’s close, maybe close enough that a little core shift/rust/casting flaw allows water to enter the hole. I have seen video of a guy chasing a rear main seal leak. The video is of the crank pilot hole in an aftermarket crank. Spin the oil pump with a drill and oil comes out of the pilot hole!!!!! Doh!!
 
All right everyone. After taking a few weeks off from cars to do spring yardwork I decided to put my big boy pants on and try this again. Same heads, heads have been shaved .025. Everything I read says that's no big deal. I cleaned the block and heads with razor blades and acetone. I used Fel Pro 521SD gaskets. No Leaks!! :). I feel vindicated. My LA / Magnum hybrid lives! I will only use the heavy duty gaskets from now on. I learned some small blocks have blind holes, some do not. I learned the Fel Pro 519SD magnum gaskets and the 521SD LA gaskets have the same exact holes except the magnum gaskets have holes for the pushrods. The LA do not. Thanks for everyone's input. Hopefully this will help someone else.
 
737jetdr said:
All right everyone. After taking a few weeks off from cars to do spring yardwork I decided to put my big boy pants on and try this again. Same heads, heads have been shaved .025. Everything I read says that's no big deal. I cleaned the block and heads with razor blades and acetone. I used Fel Pro 521SD gaskets. No Leaks!! :). I feel vindicated. My LA / Magnum hybrid lives! I will only use the heavy duty gaskets from now on. I learned some small blocks have blind holes, some do not. I learned the Fel Pro 519SD magnum gaskets and the 521SD LA gaskets have the same exact holes except the magnum gaskets have holes for the pushrods. The LA do not. Thanks for everyone's input. Hopefully this will help someone else.
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Did you use the same intake gasket?
 
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