Blown headgasket. What's next?

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1994redram

1994redram

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I have about 50 miles on my 5.9 magnum swap. The engine came out of my wrecked ram. The truck had been maintained well. My grandpa bought it new and gave it to me when I turned 16. I drove it for 8 years and ended up totaling it when I got rear ended by a tow truck. I cleaned it up, added an air gap intake, headers, 2.5 inch dual exhaust, 727 and stuck it in my '70 dart. I put a junk used 600cfm edelbrock on it to fire it up but replaced it yesterday with a new 625 cfm street demon. I was out playing around and messing with the timing and carb to get it all somewhat dialed in. I was in third gear at about 4,000 RPM when it started POURING smoke out from the breather and exhaust.

Got it home and pulled it apart. Coolant system held pressure. It burned about 3 quarts of oil in about a mile. The headgaskets failed on cylinders 3 and 4 from the cylinder to crankcase. Timing is at 15-16° initial and 35 or so when revved up.

What could have made it blow in two places on different sides at the same time? I hope to have the heads checked out and cleaned up at a machine shop and new valves seals at the least. I want to make sure this doesnt happen again. I have pictures from the passenger side head but my phone died when I did the driver side.

20171224_002342.jpg
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That engine has some time on it. So head gasket failure was eminent.
Heat/cool cycles will fatigue a gasket to the failing point.
New head gaskets,new bolts and have at er.
 
BigBlockMopar said:
Doing 100mph when still dialing in timing and a carb can do that kinda thing.
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It seemed to have been running great. No stumble or bog. Idled great. Seemed to be making decent power and didn't hear any pinging. I eased into it in second gear and let it hit 3rd at WOT.
 
Lots of engine changes and a new carb and pushing the timing up..... you could have easily been on the verge of lean on some cylinders with all the changes and the resulting unknowns, and detonated 'just enough' with the sudden load increase of going to 3rd gear. Fuel/air mix to all cylinders won't typically be the same in a carbed engines so having 1-2 cylinders 'go' and not others is what can happen.

The bent ring on the one cylinder looks suspiciously like that is what happened. I'd be pulling those pistons looking for broken rings or lands too.

Is there any odd scoring on the walls of those 2 bores, or odd pitting on the piston tops? Any recent overheating issues?
 
No over heating at all. There is a really bad spot on cylinder 6. I'm guessing rust stains? The truck sat for about a year after the wreck. I started it every couple weeks and drove it around to try and keep it from seizing or whatever else. But as previously mentioned, the coolant system pressure tested out good yesterday. So i wouldn't think it's from coolant. The rest of the cylinder walls have some slight and shallow up and down scratches. You can also see the thick oil buildup in the header from cylinder 4.
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I'd tend to agree with you on that spot on #6. If you found some excess or deep scoring on those 2 cylinder walls, it might be a good sign of a damaged piston ring, broken from detonation.

The fire-ring bent out like you show is from a lot of pressure inside the cylinder. Normal warping of the head or just common gasket failure would not bend it like that; it'll just burn or blow past the ring. (From what I have experienced, at least.)
 
There's still some pretty good cross hatching and not much of a "lip" at the top once the carbon is cleaned off. But the scratches and stains make me think really should overhaul it. But it ran great in the truck and was running pretty good in my dart didn't smoke or use any oil. So i think I'll have the heads cleaned and checked, then put it together and hope for the best. I'll take it kind of easy on her until I build an engine for it later.

So detonation is what I need to be looking out for when its back on the road? What ballpark timing should I be at?
 
I would say fixin it would be next. Yeah. That's what's next.
 
Change the gasket and run it!
Otherwise you'll find yourself rebuilding the whole thing. Seen worse that ran another 50k
 
simple , you took it out , beat the **** out of it , blew out the head gasket and now it doesn't run. rebuild it , beat the **** out of it some more, blow it up , rinse , repeat , lather , rinse , repeat......
 
73AbodEE said:
simple , you took it out , beat the **** out of it , blew out the head gasket and now it doesn't run. rebuild it , beat the **** out of it some more, blow it up , rinse , repeat , lather , rinse , repeat......
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And might I add...welcome to hotrodding son
 
It's all because the head gaskets were never re torqued after two wrecks.

Just kidding kinda.:D

The head gaskets were trashed before it ever went into the car.
That's what the standing water rust in the cylinder was caused by when it sat for the year I'd bet.
Look at how crappy the compression ring contact area's on the heads and cylinders is.
Steppin on it just pointed out the weak link is all.
 
1994redram said:
So detonation is what I need to be looking out for when its back on the road? What ballpark timing should I be at?
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I'd back it back down about 5 degrees for now and just starting sneaking it up again. Any way you can afford an AFR gauge so you can see where you are at for fuel mixture? Sure takes the guessing out of things....

Are/were you running 93 octane fuel?

And I suggest having the heads checked for flatness while you are there..
 
I'm running 91 non ethanol. I can get an AFR gauge. I've been looking at them but figured I would go crazy trying to set it dead perfect.
 
1994redram said:
I'm running 91 non ethanol. I can get an AFR gauge. I've been looking at them but figured I would go crazy trying to set it dead perfect.
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Well, that IS a possibility with an AFR...LOL. It is just easy insurance when you start to push things. (Easier to read than plugs, IMHO, especially with the newer fuel formulations.)
Just concentrate on:
- Getting the AFR in the 12's at WOT
- Don't worry over a 14 or 15 AFR at light cruise
- Don't fret if it reads off when the engine is cold; it will be inaccurate as long as there is ANY liquid fuel in the intake mixture.

I'd move onto 93 octane if you can get it. The 91 octane that guys are limited to on the west coast and some other places seems to be more problematic for compression and ignition timing, based on some discussions here. Understood on the non-ethanol being desirable to avoid the gelling crap.
 
There isnt anything close to me selling 93. There are several gas stations north of OKC which is about 30-45 minutes away that sell 93 and they even have 100 at the pump.
 
F it, slap two new gaskets on it and drive it for another 8 years.
 
Gotcha.... maybe OKC is one of the areas where some agency has decided the fuel need to be more regulated, like for reformulated fuels. (OKC does not appear on the EPA mandated list that I can see...) Based on the experiences of others, the 91 appears to call for being more conservative with compression and timing.
 
I don't know what year your motor is but dodge had a problem with the 5.9 with the heads cracking between ports so make sure you get them checked cracks are quite visible when you clean heads with wire brush between valves 1998-2001
 
Well, i had set aside my Christmas bonus with the plans to paint this dart. But there was a new set of Hughes EQ 2.02 heads on Craigslist local to me. And my dad has a freshly machined 5.9 block and crank with a new set of sealed power pistons. His plans fell through so he said I could have the block, crank, pistons, etc. I picked the heads up yesterday for a sweet deal.

So instead of bolting mine back together, I'm going to build an engine. I should have rebuilt mine before sticking it in the car to begin with!
 
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