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billsnogo 05-25-2009 04:33 PM

Headgasket or cracked heads?
I ran my car just a few days ago, and after letting it warm up, I moved it forward and there were puddles of anti-freeze where my mufflers are.

I had this once last fall just before putting it away, and tried to do two cooling system pressure checks and both times they held for about 10 minutes (until they popped out and anti-freeze when everywhere :mad: ).

The car ran hot a couple times last year do to electric fan quiting. It never ran warm on the highway after that, but did at low speeds.

So, how can I tell if it is a headgasket or head other than taking it apart? No anti-freeze in the oil, yet......

I rather not pull both heads as the bbc heads are heavy and am sure a pita when still in the car.

thanks in advance :welcome:

curtis73 05-25-2009 07:39 PM

No real way to tell. Any diagnosis you do could apply to both problems. And either way, the fix is the same. You have to pull the head. If you suspect that the head is cracked, have it fluxed.

Either way you have to pull the head and put a new gasket on it.

Deez 05-25-2009 08:06 PM

+1 ^^^

The weight of the heads is not a good reason to avoid the issue at hand. JOY

billsnogo 05-26-2009 04:53 PM


Originally Posted by Deez
+1 ^^^

The weight of the heads is not a good reason to avoid the issue at hand. JOY

Tell that to my back :mwink:
I just rather not do it, but it looks like there is no choice.

So..... my next question. Is it pretty easy to tell if it is a headgasket? Don't they usually stick to the head/block and tear in the process of taking them off?

Jake_Dragon 05-26-2009 05:01 PM

Have you done a compression test? That will tell you what cylinders to look at when you pull the heads.
Unless its obvious by the steam on the exhaust gasket. :(

curtis73 05-26-2009 11:21 PM


Originally Posted by billsnogo
Tell that to my back :mwink:
I just rather not do it, but it looks like there is no choice.

I have stage 3 degeneration in my back, and I work in a shop doing exactly what you're planning on doing. It requires three trips a week to the chiropractor :) Seriously, just use your noggin. Ropes, pulleys, engine hoists, 2x4s, whatever it takes. Your head gasket issue doesn't care if your back is hurting. Get it taken care of.


So..... my next question. Is it pretty easy to tell if it is a headgasket? Don't they usually stick to the head/block and tear in the process of taking them off?
Usually pulling off a head gasket is a messy thing that usually destroys the evidence. but its possible that you will be able to see where it was leaking on either the deck, the head, or the gasket. But don't count on it.

billsnogo 05-27-2009 04:50 PM

So I pretty much need to have the heads pressure checked either way, right? :boxing:

boatbob2 05-27-2009 05:34 PM

checking for blown head gasket...
Hi,pull the distributer wire,remove all plugs.get a SCREW IN compression guage,pep boys? do a compression test on all cylinders.write the comp # down.if,you have a blown head gasket,more than likely you will find 2 cylinders with low compression.(as compared to the rest.)example: if the first 2 cylinders on the drivers side are low,thats PROBABLY where the gasket is you only have to pull one head to change that head gasket. if only one cylinder is very low,,the gasket is probably blown away from other cylinders. while youre at it,with all the plugs still out,take a squirt can of oil,and give a cylinder 2 squirts,then do another comp check ,do all cylinders,if the comp comes up5 lbs or so,the rings are good,if the comp comes up 15 or 20 lbs. time to re-ring that engine.check the valves on the head you pull...have fun.

fast68 05-28-2009 02:17 PM


billsnogo 05-28-2009 05:13 PM


Originally Posted by fast68
one way we check for water in a cylinder is to use a radiator pressure pump and pump up the cooling system and pull the plugs all out and crank the engine over and see if water comes out any of the plug holes

if so then start pulling parts and old gaskets.

goood luck

Sounds like a good idea :thumbup:

I tried using the pressure gauge and got pretty much 160psi on all eight cylinders. So how can that be? I am getting frustraded and don't know how a cracked head or blown gasket would still hold cylinder pressure.

Just to give more info, I never noticed the anti-freeze coming out when the car ran, only after it had sat, and no white smoke plumes from the exhaust. :drunk:

thanks so far guys :welcome:

T-bucket23 05-28-2009 05:20 PM

Look at the plugs, if one is real clean that will be the bad cylinder. The other possibility is you could be sucking coolant across the intake gasket. Look in the runners before you pull the heads.

billsnogo 05-29-2009 07:53 PM


Originally Posted by T-bucket23
Look at the plugs, if one is real clean that will be the bad cylinder.

Good suggestion, except two from each cylinder bank were pretty sooty, and the other two from each bank were only lightly sooty.

I had someone suggest a leaking head bolt. Would it be possible for the coolant to run from a coolant jacket up the bolt and down into the headers? Might explain why no big puffs of white exhaust smoke? Just guessing here.

Might rent another coolant system pressure tester and pump it up and see if I can see any coming out of an exhaust port as I have the headers off right now do to the start of the tear down.

thanks again guys for the help so far :thumbup:

cobalt327 05-29-2009 09:00 PM

A crack will not always show up until the engine is up to temp, then the leak will be evident. After the engine cools down the leak is all but nonexistent.

Do the compression and pressure tests w/the engine hot.

When you do the compression test (hot or cold), set the parking brake, block the wheels, disconnect the ignition. Then block the throttle wide open and crank the engine over- only let the gage "pump" three times- don't keep cranking until the gage quits rising. You need to be able to see the gage as you crank the engine.

You can have only one cylinder that pumps bad if the leak is between a cylinder and a water jacket.

When you do the cooling system pressure check, if you can, get the engine up to operating temp. w/o the cap on the radiator. Shut the engine off and pressurize the cooling system, then remove the plugs.

Keep the system pressurized until the engine has cooled off, then crank it over to see what cylinder the water comes out of.

If you choose to keep the cap on while the engine is warmed up, carefully remove the radiator cap by using the "first click" position to relieve the pressure if you don't have a pressure relief lever on the cap.

ericnova72 05-30-2009 01:15 AM

Before you get carried away, are you absolutely sure that it is anti-freeze on the floor and not just condensation from the mufflers after parking it from a run on a night with high humidity and cooler air temperatures? Did you do a taste test of the fluid on the floor, and/or was it sticky? Although it is slightly unpleasant, the taste test never lies.

I've seen enough water from condensation come out of tail pipes to cause two dirty watercolor "paintings" on a garage door, and water drool and splatter from tailpipes.

billsnogo 05-30-2009 05:35 AM

Unfortunatly, yes it is the sweet tasting green stuff. Trust me, I tried to convince myself it was not the last time, but can not ignore it anymore. Time to tear into her....

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