What Block To Build Off Of?

[DZZ71]

I have a 599 with some cracking around the bolt holes and a broken starter bolt hole that is fixable. Next is a 141 with no cracks or defects that i could see over the many times i went over it. That block was a pull out from a 1997 1 tun it also has squirters 301,000km. Last is my 506 It was a brand new GM long block installed in 2001 over a warrentee claim the owner told me. It has about 340,000km on it. Im not sure on the cracking issue on the 506 i havent stripped it down yet. The goal is to get as much power as possible. So what would be the best one to hold up? I can post pics if requested.

 

[NVW]

The 141 should be a non squirter, 506 is the only squirt block I'm aware of.

Which bolt holes on the 599 are cracked?

 

[turbonator]

Also, check in the valley of the 506 block, to see if the Navistar (diamond) emblem is there. If it is, this is the new casting of the 506 block that continues to this day. On the back passenger side of block is the date codes for the casting. Quite possible if the #'s come up right, this would be the block we would use.:agreed:

 

[DZZ71]

This is the 141 with squirters

 

[great white]

They're all well seasoned blocks by this time.

I would use whichever one is "crack free".

If that 506 is a navistar casting and crack free, that's a keeper!

whichever one yo go with, get it magnafluxed to know for sure....before you get any machining done.

 

[tanman_2006]

599 sound like an experimental/project to see if a cracked/typically ruined block can be salvaged.
141 Good choice being seasoned w/o cracks but I would still be cautious
506 if it is newer navistar then why are you asking??? If not then cracks will determine usability.

 

[DZZ71]

I don't know if it's a navistar I'm goin on the assumption it's not. I will find out hopfully this weekend. We got a whack of snow here over the weekend so I couldent really haul the truck into the shop to pull the engine.

 

[DZZ71]

finnaly got the engine out, dident see any diamonds in the valley but got some numbers. Could anyone tell me the cast date on the block? And if its different then any other 506 block? Thanks

//http://i670.photobucket.com/albums/vv65/DZZ71/506015.jpg
//http://i670.photobucket.com/albums/vv65/DZZ71/506016.jpg
//http://i670.photobucket.com/albums/vv65/DZZ71/506017.jpg
//http://i670.photobucket.com/albums/vv65/DZZ71/506018.jpg
//http://i670.photobucket.com/albums/vv65/DZZ71/506019.jpg

 

[DZZ71]

 

[DZZ71]

 

[great white]

C291 should be a cast date of march 29, 2001.

No navistar diamond in the valley would seem to indicate in was cast pre navistar casting runs.

As I understand it that is...

 

[DZZ71]

So from what im getting is this block is no different from anyother 506 then.

 

[buddy]

Well, GM sold off in 2000 I think, so although the casting may not be different, the metallurgy might be.

 

[DZZ71]

Well, GM sold off in 2000 I think, so although the casting may not be different, the metallurgy might be.

So Tom if you were in my shoes what block would you choose? Asuming the 141 and 506 are both crack free? I'm gonna start stripping down the engine this week and get the ball rolling on this build now that I'm
Home.

 

[NVW]

This is the 141 with squirters

One thing I noticed with the second pic is there is no 4 between the 1's that I can see.

 

[DZZ71]

It's for sure a 141. It's stamped on the back I can take a photo if need be

 

[buddy]

So Tom if you were in my shoes what block would you choose? Asuming the 141 and 506 are both crack free? I'm gonna start stripping down the engine this week and get the ball rolling on this build now that I'm
Home.

I would use the newer 506, because by 2000 they had smaller squirter holes and better machining in place.

 

[DZZ71]

Is that right. I will post pictures of it stripped down in a couple days.

 

[great white]

I'd use the 506 if there's no cracking evident.

I'd use it over the 141 because it's a seasoned block that shows no signs of cracking (proven good casting) and you would gain the added advantage of oil cooling jets to the piston crowns.

Have it magnafluxed or LPI'd before sinking any money into machining or parts though.

<Fingers crossed for crack free block>

Make sure you check all the usual areas:

1. Cap bolt holes in the main journal webs that don't extend past the depth of the holes (repairable)
2. Cracks in the cap bolt holes that extend into the main webs (terminal)
3. Cracks in the main cap registers (terminal)
4. Radial cracks in the cylinders, most usually prevalent in passenger rear cylinder at the deck (terminal)
5. Head bolt block holes (jury is out if these are repairable or terminal)
6. Starter mounting holes for cracks or broken off (sometimes terminal, sometimes an irritation)
7. Cracking at the oil jets. May radiate into the webs or cylinders (terminal)

Then there's the heads for cracks between the valve seats. If you do end up chucking the heads out, keep the precombustion chambers. They should be "diamond" chambers in a 2000, the most desirable stock ones. The need to be inspected for cracks around the openings into the cylinder.

There may also be concerns with core shift, warped sealing surfaces, decked block, etc, but that can show up in any rebuilder block. The machine shop (or a straight edge) can check these for you though...

 

[tanman_2006]

4. Radial cracks in the cylinders, most usually prevalent in passenger rear cylinder at the deck (terminal) NOT ALWAYS

I have heard from the local machine shop that this can be fixed with a sleeve if the rest of the block is worth the coin.