Engine/Transmission (1994 - 1998) ? about #53 12 valve blocks

[mechanic]

I just bought a 98 12 valve with a #53 block. It has been worked hard at least part of the 115,000 miles. (It had a fifth wheel hutch in the bed and OE overloads and add on air bags. (also a gear vendors o/d) The diff. is noisy and has a little "negative preload" on the pinion brgs. , so I concluded that it has most likely worked hard. ) My question is, has anyone seen a 12 valve #53 block crack? Just wondering.

I bought the truck knowing it had the potential to crack, but the whole truck is so slick that I took the risk. I have my own shop and am a pretty fair welder if it does crack or I might use the old cold weld method using taper plugs.

Any feed back would be appreciated. Thanks.

 

[Johnstra]

Hey, Mechanic. I'm in the same boat having bought a 53 block 12V, except I don't have a shop and I can't weld for ****. I searched and never found anyone that reported a cracked 12V #53. One poster on here (can't remember his handle) says the 12V #53 blocks are different than those in the 24V. He says the walls of the 24V #53 blocks are thinner than those used in the 12V. Can't remember why - I think he said so they'd heat quicker for emmissions compliance. I'd sure like to know if that's factual.

-john

 

[ALeavitt]

How to determine #53 block?

and that makes me ask, where/how does one know if he has the #53 block??

 

[Johnstra]

On the driver's side of the block, just above the oil pan and directly below the vacuum/PS pump. If it's a #53 block, you'll see raised letters on the block that say "53". The letters are about 2 inches tall so they're hard to miss.

-john

 

[RacinDuallie]

On the driver's side of the block, just above the oil pan and directly below the vacuum/PS pump. If it's a #53 block, you'll see raised letters on the block that say "53". The letters are about 2 inches tall so they're hard to miss.
-john

Look Here:

 

[JGK]

... One poster on here (can't remember his handle) says the 12V #53 blocks are different than those in the 24V. He says the walls of the 24V #53 blocks are thinner than those used in the 12V...

-john

I don't think there's any difference - the same block was used as the 12v transitioned into the 24v. Primarily only the head and injection pump changed. I think later on the block was modified when the foundry realized the problem (block cast without a fillet inside in the area that cracks), but I'm inclined to think if its a 53, you're at risk, regardless of the number of valves. However, having said that, I think you're at a very small risk.



Piers sent me a few pictures of a 53 block that he said was prone to cracking. The outside surface of the block in the area where the crack occurs had a somewhat porous, rough look to it relative to other areas around it. So if the surface looks and feels smooth over the entire area (passenger side, above the oil pan), I'd quit worrying about it and just drive the beast!



BTW, mines a 53 and I just check it from time to time when working on the turbo or whatever, but I won't loose sleep over it.



-Jay

 

[Vaughn MacKenzie]

From what I've read it was one certain foundry that misinterpreted the prints that made the faulty #53 blocks. There was more than one foundry casting #53s.



I also think the '98 12v may have the same block as the '98 24v. If you're buying main studs I know they are different than the '97 & down blocks and there's some other minor differences.

 

[mechanic]

Hi Vaughn,

That is interesting about the problem blocks comming from one foundry. It would be helpful if Cummins would release the information on them so we could tell which ones are likely to crack. But then that would be a little self incriminating, so that is not likely. I have never heard of a 12 valve #53 cracking, that is why I posted the question. Have there been any 98 - 24 valvers that have cracked? Just wondering if the bad blocks didn't show up untill late 98 of something like that. ???

This truck has worked hard enough that I am not overly concerned about it. But I guess any of us who get a #53 would like to get all the reassurance that we can. Thanks for the information.



By the way, I saw another thread where the discussion was about top speed. You said that you saw a fast one that had an overdrive. This truck in "double overdrive" is turning 1600 at 70 mph. It has plenty of power to pull itself without a trailer. So in theory, it should turn well over 115 conditions permitting. This engine pulls good up to 2700 - 2800 RPM, so some day I may try it an see. I'll keep you posted.

 

[NIsaacs]

Since your truck is 2-wd w/auto, I would say you are safe. If the #53 block was in a manual truck with a "pop the clutch kinda driver" or a 4x4 that was used to jump or rough off highway style racing, then maybe it might crack. This will put a lot of stress on the motor mount, it is big and has a lot of leverage on the block. If I were you I would sleep just fine!





"NICK"

 

[Jim Fulmer]

Don't sweat the (53) 12V's, my old block was a 53 as well as the new re-build, but I only push them a little!



Jim

 

[biggy238]

It has plenty of power to pull itself without a trailer. So in theory, it should turn well over 115 conditions permitting. This engine pulls good up to 2700 - 2800 RPM, so some day I may try it an see. I'll keep you posted.





Mechanic, Mine ran out on flat ground, completely stock and 35 inch tires, at 115 mph.

You should be able to pull just a bit more with that overdrive unit. Either way it's faster than I trust the front axle to go.

 

[mechanic]

Don't sweat the (53) 12V's, my old block was a 53 as well as the new re-build, but I only push them a little!



Jim

Yah yah,

"Just a little bit". Thanks for the feed back, that is incouraging.

Mechanic