Help me diagnose why my head gasket blew

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With the results you have and parts used you did not get a square decking operation. You got the block decked. If it was square decked he would need the BHJ fixture or the right machining center to do it and you would have much less variation. With K1 parts and a decent crank (not Eagle cast...) you will have variation of less than .001" side to side and front to back.
If the heads were just bolted on and not corrected that would explain all the oil getting into the chambers too. They look horrid.
So - the compression is too high, there's oil contamination in the chambers, and the PCM doesn't know what you changed so it's just going through the motions. You need to drop the compression and rethink the build. You need to stay within the PCM's operating range.
 
moper said:
With the results you have and parts used you did not get a square decking operation. You got the block decked. If it was square decked he would need the BHJ fixture or the right machining center to do it and you would have much less variation. With K1 parts and a decent crank (not Eagle cast...) you will have variation of less than .001" side to side and front to back.
If the heads were just bolted on and not corrected that would explain all the oil getting into the chambers too. They look horrid.
So - the compression is too high, there's oil contamination in the chambers, and the PCM doesn't know what you changed so it's just going through the motions. You need to drop the compression and rethink the build. You need to stay within the PCM's operating range.
Click to expand...

So is the oil contamination the cause of all of the carbon?

This was my first engine build, and I made some mistakes, I thought I did all the research that I need, but apparently not.

You are correct the Eddy heads weren't checked out. This was before I knew that Eddy heads need to be checked. They claim they are ready to run out of the box, but I know better now. What problems do they have?
 
JGC403 said:
You are correct the Eddy heads weren't checked out. This was before I knew that Eddy heads need to be checked. They claim they are ready to run out of the box, but I know better now. What problems do they have?
Click to expand...

Piece of advice... EVERYTHING should be checked, always. It's all mass produced, and most of those parts need tweaking. Yep, it sucks to shell out cash for brand new go fast parts, then shell out more cash to have a good machinist check and correct anything that needs to be. BUT, it saves you bigger money, and time in the long run! As you just found out...

Hope you get it resolved, and good luck to you! :)
 
look into the intake ports...do you see oil on the intake valve......I had a problem with the valve seal on the eddy heads....within a year or two they were leaking oil....
 
70aarcuda said:
look into the intake ports...do you see oil on the intake valve......I had a problem with the valve seal on the eddy heads....within a year or two they were leaking oil....
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It doesn't look like any oil was running down the valve stem. But there is a lot of junk built up on the back side of the intake valve.
 
Well, we live and learn. Nothing lost here but time and money.
You have a some issues in my opinion but I don't I can be much help on one of them...
1. The build is too much for factory PCM controls. It's a very common problem - but I don't have much experience with it. My fix would be a stand alone management system and that's probably way too much money dna time. Hopefully someone with factory EFI Magnum experience can shine some light on approaches for this.
2. The machining is questionable. That you can address and hopefully the shop works with you on it.
3. Edelbrock heads suffer from what everyone's heads do - production line workmanship. The valve guide clearance is ususally all over - some really tight, some really loose. That's normally where the oil comes from. Also - the seat machining sucks so they don't always seal the cylinders as well as they could and the rocker geometry can be screwed up. I'll add the decksurfaces can be too rough for some gaskets too - although in this case I'm sure that's not an issue.
4. The assembly. Did you do this yourself or ahve a shop do it? Oil in the chambers can also come from rings, which can commonly be cause by assembling them on "dirty" bores. Did you wash the block with brushes and soapy water? Did you wipe the bores with brake cleaner and white paper towels in the directions of the honing patter until the towels came out clean? Were the head bolt holes tapped and blown clean to clean the threads? Was head bolt and dowel pin engagement checked to make sure you were torquing the head and not bottoming out the bolts?
 
moper said:
Well, we live and learn. Nothing lost here but time and money.
You have a some issues in my opinion but I don't I can be much help on one of them...
1. The build is too much for factory PCM controls. It's a very common problem - but I don't have much experience with it. My fix would be a stand alone management system and that's probably way too much money dna time. Hopefully someone with factory EFI Magnum experience can shine some light on approaches for this.
2. The machining is questionable. That you can address and hopefully the shop works with you on it.
3. Edelbrock heads suffer from what everyone's heads do - production line workmanship. The valve guide clearance is ususally all over - some really tight, some really loose. That's normally where the oil comes from. Also - the seat machining sucks so they don't always seal the cylinders as well as they could and the rocker geometry can be screwed up. I'll add the decksurfaces can be too rough for some gaskets too - although in this case I'm sure that's not an issue.
4. The assembly. Did you do this yourself or ahve a shop do it? Oil in the chambers can also come from rings, which can commonly be cause by assembling them on "dirty" bores. Did you wash the block with brushes and soapy water? Did you wipe the bores with brake cleaner and white paper towels in the directions of the honing patter until the towels came out clean? Were the head bolt holes tapped and blown clean to clean the threads? Was head bolt and dowel pin engagement checked to make sure you were torquing the head and not bottoming out the bolts?
Click to expand...

Yeah, my first engine build and I know I mad a couple mistakes. Like you said just time and money.

Well I decided to take the heads to a machine shop. I'll be doing that today. So hopefully that will all get worked out.

I assembled it myself. I bought an engine brush set when I did this and I cleaned it in and out. I did not check head bolt engagement.
 
I agree 100% with the others about the rod length and all, but I'll be damned if I wouldn't take that block back and let them remeasure it. From those measurements you took, the block deck could be cut uneven on that side. Just something to think about.
 
JGC403 said:
Pistons come out of the hole and aren't all the same:

#8=0.009"
#6=0.007"
#4=0.016"
#3=0.017"
Click to expand...

#3 and #4 are on the #2 rod journal and are both out the hole like amounts. IMO the crank is likely not stroke equal. I bet that the rest of the pistons share similar piston to deck height for their rod journal.
Have the heads cleaned up, guide clearance set to .0016 int / .0018 exh. Touch up the valve job, with a deshrouding cut added, and a little bowl work. Eddy heads use some of the worst valve seals out there. Black rubber junk. Replace these with metal clad blue viton seals. Normally I'd recommend a FelPro 1008, but the piston to head clearance on #3 & #4 would be like .025. Way to close IMO. You could use a FelPro 8553 to gain some clearance, but those gaskets really aren't good choice for aluminum heads and high compression IMO.
Unfortunately this motor should be pulled and torn down to figure out the piston to deck height issue. Stroke length, rod length, piston pin height all checked. Then set it up for .000 deck for proper quench clearance with a 1008 gasket. This may entail having the pistons fly cut down as the block's decks are likely too short.
I agree with Moper, the PCM probably isn't able to run this combo correctly.
 
I'll update this thread. I decided to pull the block and take it to the machine shop to have it checked out. When I built the engine a couple of years ago the machine shop was supposed to align hone the mains and square deck the block. Got a call from the machine shop a couple of days ago. 2 of the main bearings are ruined because the align hone wasn't right. The crank will have to be turned down 0.010" because of this. The deck is off from front to back top to bottom and bank to bank. So basically I am better off starting with a new block. So now I'm on the hunt for a 5.9 magnum block.
 
If your crank is going to the crank grinder have them verify the stroke and index. Definitely start with another block, sounds like the old one is a lost cause. It sucks that the shop couldn't get such basic block machining operations right. Might want to have the block bored, then check the piston to deck height so as to know just how much needs to come off the deck to achieve 0 deck.
 
that's good - you found the issue... and bad - you paid good money and the whole thing has to be redone.
There is a huge difference in machining quality place to place. Magnums are easy to come by but just out of curiosity - if this block has already been run, magged, checked, etc.. Why not use it? Have the operations done (main hone, honest square decking, etc) and put fresh rings in it and go. At least you cut out the 2nd initial cost of buying, cleaning, and checking, and you've already had it bored... Or are there problems there too?
 
If the shop that checked is the same that did the work the first time, is there any money coming off for the rework? If not I would personally take it somewhere else or get a guarantee in writing. Or at least some cut in price.
 
I reckon it depends on where the deck is NOW. If it was zero decked last time, then it's toast, unless you want a positive deck height. That's ok if you have room for the increased compression.......but you have to wonder how much it is going to take to get that block back straight again. I guess it's a good thing you found out like this, instead of a pile of mangled parts under the car. It could always be worse. Good luck with it and please keep us posted.
 
The pistons come out of the hole already with this block. And the heads are going to get resurfaced so that will lower the combustion chamber volume increasing compression even more. So to make this block work I would need to get a thick MLS head gasket. So the shop and I agree that I would be better off starting with a fresh block.

No this is a different machine shop. I built the engine originally while I was down in AZ. Now I am in PA. This shop was recommended by a friend who races every weekend, and I trust him.
 
Damn. It's becoming a chore to find trustworthy machine operators.

I feel like Edelbrock needs to ramp up their quality control. I almost bought an air gap manifold from a swap meet for dirt cheap. Measured the runners, side to side to find about 5/32" more distance core shift in the runners on the right side. Over 1/8" and I'm not even sure you would get a runner divider to seal on the shifted runners.

Anyway, I think you made the right move with the new block/ stock deck.

Those pistons should run fine on a square zero deck or even in the hole a bit, on that gas. I've got a 9.75 @ .012" below deck on a +5cc piston, so I do believe that 10:1 is right at .015" on these engines with a flat piston.

It looks like the quench on your pistons was designed for zero deck, check the dish cc on those and punch some numbers into a calculator, with the gaskets you want, before you have everything cut.

Also, for what it's worth, I know that bad quality fuel is an issue here in CO., A friend of mine had a lot of lab tests run on water content from a lot of stations here and he and his master technician from his school discovered that the 87 (mid grade) has a much more stable octane rating within it's numbers and a lot less likelihood to have water in it, because of it's extra refining. It's not much higher than 85, but the quality wasn't even comparable from his lab results.

He also said that gas from small stations with older tanks were significantly cheaper in quality with higher water content, on 85 octane.

Also, octane boosters are a waste of money. They claim to raise octane rating a point or two or five or whatever. The truth is, they do. They raise 87 octane (as an example) from 87 to 87.2/ 87.5, etc. The labeling is very misguiding.
 
I think in terms of water in the fuels - that's a side affect of the ethanol mix (10% here in CT). So it's not refining, but time int he ground. Older smaller places have older tanks in terms of both technological and sealing quality, and the lowest grade (cheapest) moves the quickest from tanker to cars' tanks. I will only get fuel from a few big name (Mobil or Shell) places - all have had tank replacements within 5 years (we've had the 10% blend at least over the winter for about 8 years now). Up here tank replacement is mandatory after 15 years. I also only run premium fuel and I would swear the cheaper places (7/11, Citgo, etc) have a higher percentage of ethanol. They smell much different and I lose about 2mpg running them even at the same octane.
 
Well I want to update this thread. Finally got the engine back from the machine shop last weekend.

I posted in a previous post that the block wasn't machined correctly the first time and that is what caused the head gasket to go.

The Eddy heads were re-surfaced and the spring pressure were checked. The springs that came with the heads, the spring pressure were all over the place. So new springs were installed to match my cam. New seals, cause the Eddy ones aren't that great that come with the heads. Also a valve job was done.

MLS head gasket were used this time to get the compression where it needed to be.

We decided to re-use the block that I had. So I had to get new .030" over pistons. That were also cut to get the correct compression ratio.

Finally the intake had to be milled a little so that fit correctly.

I think that is pretty much it.

Now its just sittin in the garage cause its to cold to install it.

 
Hope your motor runs as good as it looks and all your problems are behind you!
 
I may be an hour late and a dollar short but here is my opinion. PING!!!! You mention it had a ping. Pinging is caused by improper detonation. Either by hot spots, low octane fuel, excessive heat, or too much timing (picture hitting the oxygen lever on your acetylene torch and it will give you a visual). I have found timing to be the culprit in most cases. You may have too much or too soon advance curve in your total timing. Your hot spot was where the gasket failed. Find the cause of the ping and you shouldnt have any more gasket troubles. Dont rule out that the gasket could have caused the hot spot and destroyed itself. Although If your PCM is stock and your engine is not, I'd bet it cannot adjust enough within its original perimeters. You may need a chip at the very least or even an aftermarket PCM. The chambers dont look lean but unless you pulled the heads after a hard run it will only represent the idle mix which is probably way too rich to compensate for the lean driving condition. I'd find a good performance shop in your area to work out your PCM woes or invest in a good programmer and start teaching your ride how to play nice. David
 
I never had any luck with the gas booster, try some 112-or 116 put a gallon to a tank full with your 93. Mine blew due to detonation also, Use thick head gaskets and good fuel for now. Might be able to recurve your dizzy to help with ping.
 
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