Plymouth 383ci Big Block question

[Johnny Turbo]

I cracked a 440 block in the valley area once.

Oooh ‍

Any idea how it happened?

 

[Big_John]

Oooh ‍

Any idea how it happened?

Yep... My own fault.

This was 45 years ago. I forgot to drain the block on the drag car. It was a very late night, I was exhausted, and I left the car outside on the trailer. The tracks always wanted us to run straight water, so no antifreeze. The temperature dropped to the high 20's and it was just enough to crack the block.

 

[Xcudame]

Yeah, the more I think about, the heads are coming off. The compression check might help point to a blown head gasket which would be a whole lot better than a cracked cylinder head or block. If you look at the head gasket, the thinnest spots are between cylinders and between a cylinder and oil passages. At this point I'm hoping that it's a blown head gasket or at worse a cracked cylinder head and not your block!!

 

[Johnny Turbo]

Yep... My own fault.

This was 45 years ago. I forgot to drain the block on the drag car. It was a very late night, I was exhausted, and I left the car outside on the trailer. The tracks always wanted us to run straight water, so no antifreeze. The temperature dropped to the high 20's and it was just enough to crack the block.

Dang no fun.

I guess anything is possible with this car. The story i got was it was sitting for years. The guy in bought it from "got it running, put the tunnel ram on it, but couldn't figure out why the brakes never worked" so he "never really drove it."

The brake fix wasn't to bad. I figured due to the tunnel ram, it didn't make enough vacuum for the booster to work properly. That was part of the issue. The brake booster was bad, and my guess is he couldn't find a replacement. Because no one sells new ones that I could see and few rebuild them. Rebuilds are pricy.

I bought a LEED booster kit and made it fit. I also added a brake booster vacuum pump. So the brakes are now no longer an issue.

Only thing stopping it from hitting the streets now is this coolant in the oil issue.

 

[Johnny Turbo]

Yeah, the more I think about, the heads are coming off. The compression check might help point to a blown head gasket which would be a whole lot better than a cracked cylinder head or block. If you look at the head gasket, the thinnest spots are between cylinders and between a cylinder and oil passages. At this point I'm hoping that it's a blown head gasket or at worse a cracked cylinder head and not your block!!

Yeah we are definitely on the same page with that.

I'll try to keep you all posted, once I get time/weather to pull it apart

 

[Johnny Turbo]

Yeah we are definitely on the same page with that.

I'll try to keep you all posted, once I get time/weather to pull it apart

I had another thought to run by you all. Due to the snow I haven't had a chance to check.

Could it be as simple as an intake gasket failure? Could that allow coolant to creep into an intake port and or pushrod/valley area and then down into the oil pan?

(Just thinking out loud)

 

[Big_John]

I had another thought to run by you all. Due to the snow I haven't had a chance to check.

Could it be as simple as an intake gasket failure? Could that allow coolant to creep into an intake port and or pushrod/valley area and then down into the oil pan?

(Just thinking out loud)

Intake on a big block Mopar doesn't have coolant running through it. The small block does.

 

[Johnny Turbo]

Intake on a big block Mopar doesn't have coolant running through it. The small block does.

Well that answers that. Thanks.