Ughhhh....could it be a gasket issue???

[bth0320]

Hi folks,

Wondering if anyone has had a similar issue....finally fired up my 383 after a fresh build. I bought the car with the short block already complete so not sure what machine work was done but looks to be professional. Upon firing up, it ran great but hadn't set the idle yet. It died and when trying to restart, it was hydro-locked.....quickly found the problem to be coolant was filling up cylinder #4 and of course the whole motor at this point.....literally had coolant pouring out of the end of the header. Put a new gasket on and same thing. After getting a camera, we were pressurizing the coolant system and with only 5 to 10 psi, we could see coolant seeping in around the gasket. Swapped the Eddy heads to be sure it wasn't the head and same thing so we did rule that out. Took a straight edge to the deck of the block and it looks to be dead straight....no visible cracks in the cylinder or anywhere near.....super frustrating.

I am using a fel pro 2519 PTI gasket (.040 thickness). Could it be just the gasket? I have a multi-layer gasket on order at $110 a gasket just to be sure but wondering if anyone else has had similar issues before I tear the motor apart and take the block to a machine shop?

Here is a short video on the start up....was super pumped at first how good she sounded.

[video=youtube;sy-xEUiwSrg]http://www.youtube.com/watch?v=sy-xEUiwSrg&feature=youtu.be[/video]

Thanks for your help!
Brian

 

[snakeoil24]

Sounds like the Exhaust manifold studs where not sealed and leaked in thru an exhaust valve.Or you used aftermarket bolts on manifold that did not have the shank on the bolt shoulder and it leaked back thru exhaust valve.

 

[bth0320]

Are the exhaust bolt holes connected to the coolant ports somehow?

We stuck a camera in the cylinder via the spark plug hole and through the intake valve when open (no intake is on at this point for easy viewing) and can see the coolant running down the cylinder wall from the gasket area.....there is nothing coming from the head or valves. To get this to occur, all we have to do is pressurize the system with a minimal amount of pressure and it leaks like crazy....no headers are on we are doing this and the other side does not leak.

 

[tallhair]

Yes some of the exhaust bolts go through the water passages

 

[snakeoil24]

Yes it can be a gasket issue. Usually you put a coating of silicone RTV Hi heat around the opening in the gasket around water jacket.

 

[bth0320]

So with the headers off and no bolts (not using studs), wouldn't I see some coolant leaking from these holes then when pressurized? On the "good" side of the block (cylinders 1,3,5,7), no header or bolts are installed and no leaks. These are edelbrock performer rpm heads and I just looked at the instructions and found this:

Exhaust flange has been extended out .125” in order to provide dry exhaust bolt/stud holes....

 

[snakeoil24]

Good then sounds like head gasket. Did you use a steel shim only or a multi layer?

 

[bth0320]

Yes it can be a gasket issue. Usually you put a coating of silicone RTV Hi heat around the opening in the gasket around water jacket.

I did try this around the bore and it didnt work but will try it around the water jacket to see if that does it...

 

[snakeoil24]

I t has to be only around the triangle opening in the water jacket nothing around the bore. You can spray the entire head gasket with copper spray. But nothing around bores.

 

[moparmarks]

"Swapped the Eddy heads to be sure it wasn't the head and same thing so we did rule that out."
What did the gasket look like at that point?

 

[coloradodave]

Are you sure your gasket is #2519PT1? I believe the correct gasket should be a #8519PT1 for the Fel-Pro permatorque.

 

[69Bee]

I think you mean 8519PT1 like ColoradoDave said. Also, please do NOT put any silicone or copper spray on the head gasket. You will seriously screw up the sealing properties and can affect the torque of the head. The permatorque gasket requires no extra sealing in order to work correctly.

If you are in fact using the correct head gasket 8519PT1, then I would look at a surface defect on the block. Either a low spot around a coolant passage, or the surface finish is too rough if surfaced. If someone got too aggressive when using the 3M scotch pad, it will actually wear the metal away creating a low spot. When you take the heads off again, take pics of the surface and post them.

 

[bth0320]

Sorry, that was a typo....they were the 8519PTI's. As far as what they looked like when I pulled the head, too hard to tell as they were soaked upon taking the head off since the cylinder filled up with coolant.....it did look like it was sealing around the bore as I could see the rings in the block and the head. Here are a couple of pics of that water jacket....nothing looks to be abnormal that I can see. I did see that Edelbrock recommends a Fel-Pro 1009 for aluminum heads....I am going to order up a couple different gaskets (this 1009 they recommend) and a multi-layer to see if it could be just the 8519 causing it....seems odd but sure would be better than ripping this back down.

 

[68 HEMI GTS]

the 8519 is a pretty good gasket, if your edelbrocks have stock chambers the 1009 should work though. i really gotta wonder about the deck surface, or if there's a minute crack. i would be inclined to borrow a deck plate and bolt that on with the old gasket and pressure things up just to see if you can get a better idea whats going on. if your just going to bolt on another gasket with the head you might want to go with something thicker than .039, might help soak up any surface imperfections if that is the issue. if a composite gasket isn't working the multi layer such as a cometic will probably be even worse.

 

[69Bee]

Back up a little more so we can see the entire surface. Also, as far as the rafter square goes, it is not an accurate straight edge, and it is too short to properly measure the deck. You need to use a minimum of a 24" machinist straight edge. The machinist straight edge has been ground to about 0.001" tolerance over its entire length, where as the rafter square is, well, a Lowes special...

 

[bth0320]

Back up a little more so we can see the entire surface. Also, as far as the rafter square goes, it is not an accurate straight edge, and it is too short to properly measure the deck. You need to use a minimum of a 24" machinist straight edge. The machinist straight edge has been ground to about 0.001" tolerance over its entire length, where as the rafter square is, well, a Lowes special...

It is definitely a lowes special! Here is another pic with a wider shot....not sure how well you will be able to see it on here but it does look like the gasket is not sealing well around the upper water jacket to the top right of #4. I did borrow a deck plate from the machine shop today and tried a couple of different gaskets....although they sealed better, still have some leakage into #4. Unfortunately I cant tell where it is coming from and still no visible cracks. At this point it looks like a tear down and off to the machine shop...

 

[69Bee]

This is what I kind of see with this pic...
1) This looks to be combustion or oil staining
2) These look like low spots as you can see no gasket transfer
3) Water marking a large area, possibly a low area also
4) Not sure what to make of these wierd shapes next to the water jackets
5) There seems to be a lack of gasket transfer here also



Your earlier pics look as though it might have been milled before, and it could be too smooth. A Fel-Pro composition gasket shoud be somewhere around 60 - 80 micro inchs RA. The MLS gasket you are getting wants somewhere in the low teens. The info sheet that comes with it should tell you, or the Cometic catalog will. Take it to a machine shop to check it for flatness, and depending on the gasket you want to use, have the surface it correctly. I see no other obvious reasons to leak water.

Good luck
Dave
Precision Machine Service

 

[bth0320]

Thanks Dave....you picked up a lot just from the pic! I thought those shapes (your #4) were very odd too....they are actually on the other side on the block as well where I am having no issues. Should have it to the machine shop Monday to see if they can correct this!

 

[Garys1969RR]

Only way to really fix this right is to pull it apart and take it to the machine shop. The deck of the block doesn't appear to have been machined recently, and it is prob not flat. The Block Shop in Denver did all my work on my 451 and a 383, no issues. Have them check it and the heads for flatness. That 8519 gasket should work well. I used steel shims, and no leaks. Has to be a warped deck or maybe a head. I will send you a PM and you can call if you need help, I live in the L Wood area. Not far from you. Good luck.

- - - Updated - - -

Also use the factory recommended torque sequence on the head bolts. Start at 30 ft lbs, then repeat the sequence at 10 pound increments till you get to 70 ft lbs. That pulls the head down very evenly.

 

[eric383]

Let me just relate an issue I had with a 302 I stroked to a 347. Yes I am equal opportunity and do not discriminate. The machine shop decked the block to clean it up. I assembled the motor and it ran great. I didn't get alot of miles put on so the next year it started using water. I had neglected to check how far the head bolts went into the block and with the milling I was just short of getting my max torque. I had washers that came with the head bolts but didn't think I needed them because these heads came with inserts that I thought replaced the washers to make them useable on a 351 also. Luckily I just had to replace the head gaskets and add washers and all was good. To sum things up the head bolts were bottoming out before they were able to clamp the heads enough. Make sure you don't have the same issue or have crud down in the bottom of the threads in the block