Engine/Transmission (1994 - 1998) cracked 12v block

[SRay]

Hello, my friend Jamie was sled pulling with his 1997 Dodge Cummins at Fergus fair this weekend. During the pull, his block cracked all alongside the passenger side right through the freeze plugs. Coolant poured out but other than that the engine runs fine.



The mods that were done were as follows: 215 p7100, no plate, . 024 cut delivery valves, ddp 140hp injectors, 64mm Silver Bullet turbo, 3 piece manifold, ported head, arp studs, stock head gasket, marine pistons, studded bottom end.



The Cummins pulls 60+psi boost which is around 600+hp.



We are wondering what could possibly crack this block if its not the notorious ''53 block''.

 

[DRAG DIESEL]

We are wondering what could possibly crack this block if its not the notorious ''53 block''.

um, for starters it was made for 215hp, not 600+

 

[SRay]

That's a logical answer. And this is rare to happen for such a robust part.

 

[DRAG DIESEL]

rare, no. I am sure it was spinning the factory red line of 3,000rpm's as well:-laf

 

[SRay]

So running the engine over 3,000 rpms causes stressed blocks?

 

[HBarlow]

Everything that engine was subjected to created stress beyond what it was ever designed to tolerate.

Very heavy modification, high rpm, and extreme instantaneous shock loads plus sustained very heavy load for the duration of each pull would all add up to tremendous stress levels.

How long or how many pulls did the engine survive at that power level?

 

[RSchwarzli]

How many miles on the motor?

 

[RSchwarzli]

What RPM does he run at?



I do agree that abuse in that power level will kill any motor, but does seem odd that is treated right (read not extreme rpm, not a sudden surge of boost, not a faulty casting) these motors can live at that power level quite often. Although 60psi is high, there are many motors that run a lot higher.



Something is still missing here in this puzzle. The motor build looks like it was done right. Is he running something too high for timing?

 

[GAmes]

For the record, it is possible to have a 53 block in a '97. The engine I put in mine has a build date of 10/97 and I doubt that I have the first one that was made.

 

[B.G. Smith]

Just out of curiosity, were the motor mounts or transmission mounts modified? Thanks, bg

 

[SRay]

This engine was rebuilt almost 2 years ago with marine pistons, etc. Not quite sure on the milage. This guy is a competition puller that also pulls alongside a 2002 24v that's pushing 700 rwhp.

The engine runs at 4000 rpms, Timing at 24 degrees. The engine had 390 rwhp for the first year, then came the industrial injection 64mm turbo.

Now that he told me the timing was at 24*, I think that's what split the block from extreme cylinder pressures. I assumed 16. 5* timing because that's what he had before as he blew a head gasket when he went 18* for dyno day in spring. After the head gasket, he said he backed off the timing to 16. 5*.

This engine has many pulls under it's belt over 2 years.

 

[SRay]

Also this engine is still going. The block has been welded in the truck, and a welded on plate to help hold together the day after the crack happened. Power is still over 600+ and he's pulling again this coming weekend.

B. G Smith: no these are still factory mounts.

GAmes: you're correct on the 53 block in 1997. Jamie's block is not a 53.

 

[SRay]

Factory engine mounts so far. Have you been wondering about them?

 

[B.G. Smith]

Factory engine mounts so far. Have you been wondering about them?

I just wondered if the engine was tied down solid to the frame if that could induce enough stress to cause something like that? I have seen some dirt track gasoline rigs where they removed the rubber from the mounts and welded them in solid. bge

 

[SRay]

Ok, I didn't know they do that. Not sure what would happen if engine was in solid like a tractor as these are pretty much tractor engines.

 

[Vaughn MacKenzie]

Hopefully the block won't separate completely like happens to some extreme pullers, can be dangerous and do major damage, but probably won't happen to him since he's not running upwards of 5000-6000 RPM and 1200 HP.

 

[Mhannink]

my bet is it just happened one of those fluke things. yes stress from sled pulling and high horsepower where factors no doubt but i wouldnt think its anyone thing maybe that block was just a little weak there and couldnt take it anymore