I melted a Piston, 250 Inline 6.

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jjester6000

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I was going down the interstate at about 75mph when all of a sudden I lost all power and the engine died.

The truck had been running great for the past few weeks, so I didn't know what happened.

I checked for fuel/spark, but there was no problem.

It also sounded weird when cranking, as if the plugs were out, and it had no compression

Having recently replaced the head and head gasket, I then started to think that had a defective head gasket, so I pulled the head off and found this.
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Cylinder No.6 had changed its mind about being a piston.
 
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jjester6000

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I could rebuild it, but it is a lot easier to just get another engine and swap it in.
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I have this Mint 194 I6 that I bought for the cylinder head that I could swap in.

The issue is that I would probably get lynched if I did so.

I am now looking for a new engine.

Maybe another 250, or even a 307 sbc.
 

Bextreme04

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looks like some really nasty detonation going on in there... did you not hear it pinging? I would think that much detonation should have been pretty apparent
 

Vbb199

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I could rebuild it, but it is a lot easier to just get another engine and swap it in.
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I have this Mint 194 I6 that I bought for the cylinder head that I could swap in.

The issue is that I would probably get lynched if I did so.

I am now looking for a new engine.

Maybe another 250, or even a 307 sbc.


I suppose I can understand an appreciation for old stuff.... But what's wrong with just a small block or big block v8?
 

jjester6000

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looks like some really nasty detonation going on in there... did you not hear it pinging? I would think that much detonation should have been pretty apparent

No, but I did have my radio turned way up.
 

jjester6000

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I suppose I can understand an appreciation for old stuff.... But what's wrong with just a small block or big block v8?

Yea, I am considering a sbc, but I found a great deal on a low mileage 250, and I already have a preformance camshaft/high compression head that would bolt right up.
 

Vbb199

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Yea, I am considering a sbc, but I found a great deal on a low mileage 250, and I already have a preformance camshaft/high compression head that would bolt right up.


We'll I say go for that then.

You don't hear of alot of people building them
 

DoubleDingo

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Stay with the inline if you already have one lined up. Way easier to swap in the new one.
 

Rusty Nail

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If you find a 307, rob the crankshaft for a bigger bore!

I wish I had a 307 crankshaft..:(
 

DoubleDingo

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I read 307 and thought v8, and then remembered the GMC 302, the big boy I6 for the old GMC trucks.
 

Ricko1966

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Be careful with your new install.Looks like you had an intake leak and I'd want to know why.Just looked at that pic again 1 piston a set of rings and a set of rod bearings and you'd be good. Real cheap 1 piston , 3 rings, and check the rod bearings.
 

Ricko1966

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If you find a 307, rob the crankshaft for a bigger bore!

I wish I had a 307 crankshaft..:(


307 crank with 4 inch bore is a 327. What are you wanting a 307 crank for? Curious because I just happen to have a 307 crank
 

Rusty Nail

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I own an actual 267 block..from a 1980 Caprice (3.5" bore and 3.48" stroke - 3 years in production)..and intend to build a 250V8 with it one day because i'm honery. ;)

Yep, a real live, bonafide 267 V8 Casting # 14010280.

All it needs is destroked with a 3.25" crank and i'll make a 250 V8. Ungh.
 
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Ricko1966

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Doing quick math in my head. 307/327 crank and 6 inch rods that should just about assemble itself with a stock, block, pistons. Sounds fun same kinda weirdo. crap I do.Just for fun.
 

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