BOOM!

[Ratman]

What is the whole story??? :???: At least a link to the thread???

Ok, I found it, -I copied and pasted, because I don't know how to link to it. Here is part one of two.....

This is sort of a long one...

Well, as some of you may know, I began a project over a year and a half ago when I lost a headgasket on my '94. It began with cracked heads, then progressed to small cracks in several pistons. The rig had 200k original miles, -never anything done to it except for the infamous DS-4 pump/pmd replacements by the previous owners.

I decided it would be in my best interest to tear the engine down and do it right. Well, -all was going well, -until I found a small crack in #2 and #3 main webs. You know the type, -caused from the 12mm outer main bolts in the 599 block splitting the edge of the hole open. So, at this point, I decided to look for another block.

Well, I wasn't able to turn anything up, -so I started looking at new blocks. I got on the phone, and ordered one from Diesel Direct, -along with a supposed "forged" crankshaft. When the block/crank shows up, it is a mess. I mean to tell ya, -it looked like they dropped the thing off a ten story building. The crankshaft was broken in two, -and definitely not forged.

So, after much stress and legwork working with Diesel Direct, I was able to get all my money back. Kudos to Kris at Diesel Direct for coming through, -despite the stress in the interim.

So, off to find another block and crank. One of the fellas on the other forum knows I was looking, and sends me a PM. He happens to have a year 2000 506 that is in pretty mint condition, -and the price was right. SO, I decide to order a Scat crank and get this 506 from the guy. The 506 shows up, and it becomes obvious that it needs bored/decked, -no biggie. I take it to a very respectable machinist and have the full meal deal done.

I order new heads from Clearwater, Felpro gaskets, Clevite bearings, and new Mahle 18:1 marine pistons. At this point, I am clearly committed to doing this sucker right. It goes together beautifully, -and is blueprinted every step of the way. Every dimension is logged, -and put into a spreadsheet.

The DS-4 had sat on the bench for better part of a year, -caplugged, bagged, no issues, -just bolt it up and rock and roll, -right? Hah, -fat chance. I had all the injectors gone through, -new nozzles, all the pop pressures evenly set, etc.

So, initial test-fire time....

I light the thing off, and bleed all the lines, -but there is a problem. The timing is waaay off, -and the thing ain't running right. So, I go through the motions of resetting the pump, fooling the ECT, doing the TDCO learn, etc, -yada yada. The pump will not time, -something is wrong. SO! Off comes the intake. I make a few calls to round me up another DS-4, -not hard to find with all the PMD-related "pump-failures". So, I get the "test" DS-4, -and install it, -and voila, -the thing times-up just fine. At this point, I am ecstatic. Realizing the loaner pump has to be returned, -and the fact that it idles weird, -and that I have absolutely NO history on it, -I leave the intake off until I can get the pump issues resolved. I decide to cover the intake ports with shoprags to keep the dust/dirt out until the next day.

Now, as you can imagine, I'm feeling pretty "giddy" right about now, -except, my buddy is coming over with his Modis the next day to check my timing (might run the loaner pump a while to break the engine in), -and I wanted to see how the thing idled cold one last time. By now I have a couple glasses of wine in me, -the radio is turned up, -and I've gotten a couple of phone calls. I decide to jump in the truck and give 'er one last run before calling it a night. BIG MISTAKE. The thing fired RIGHT up, -and it didn't take long for me to realize there was a problem, -it hit me in the head like a brick. I suddenly realized what I had done. I opened the hood to get the damage report. Bad news indeed, -there's coolant splattered out of the #5 intake port with about two-thirds of a shop rag inside the port. At this point, I can hear my coolant reservoir sucking down, -and it literally sounds like someone is taking a leak into my oil pan. I'm thinking, -oh no, you've got to be kidding me. So I grab a wrench, and a drainpan and whip the plug out, -yep, you guessed it, lots of green stuff. At this point, my heart is in my stomache.

(to be continued in part two).

 

[Ratman]

So, after reading part one, -you probably think I'm writing some sort of a fiction novel, -I wish that were the case.

So, after the rag incident, the engine comes back out and gets torn down. The damage report, -a cracked cylinder wall in #5, -literally from top to bottom. A bent #5 intake valve, a collapsed skirt on #5 piston (actually cracked in the undercut for the oil ring groove), -and a very questionable rod. The Scat crank survived, -with the exact same straightness as it had before the incident. I logged all that stuff, so it was easy to compare.

So, after MANY phone calls to guys "in the know", I decide it may not be a bad idea to re-visit my 599 block that has the small cracks in the outer bolt holes. One local shop said that at least four out of five 6.5's they rebuild have cracks in exactly the same place. They rebuild about 30-40 6.5's a year, -and they also re-use the blocks (and factory bolts to boot), -the bottom line? -not one has failed yet.

So, by now the gears in my head are turning. I get my 599 block tanked and have a closer look at it. I also have a mechanical engineer that I work with look closely at it. He actually models the web in solid works and calculates the stress concentration around the bolt holes. He stated that the main reason for the high torque value was to stretch the fasteners adequately so that they do not "fatigue-cycle", -which would cause a fastener failure in short order. He also concurs that using studs would likely be a good solution. The two cracks (#2 and #3) also ended at the bottom of the threaded holes for the outer bolts. He also said that the cracks clearly exhibit that they were caused from the stress that the fasteners placed on the web while being "wrung-out" in the holes. Clearly, GM knew the same thing, -hence the update from 12mm outer to 10mm outers on the later blocks.

So, ARP, here I come.

The 599 was built with the entire bottom-end studded. I special ordered the studs so that they could be threaded ENTIRELY into the holes. The 599 build went smoothly.

Some bearings were replaced, -along with a pushrod, and a new intake valve in the one head. One piston and one single ringset were replaced as well. I also opted to replace the #5 rod, -just for good measure.

Now, since I needed a new injection pump, I decided since I had the NV-4500 manual trans, -it was a no-brainer to ditch the DS-4 and go with a cranked to the max DB-2. Some minor bracketry mods to clear the 97+ crossover, a custom made fast-idle solenoid bracket and arm, a set of '93 injection lines, and voila! No more DS-4!

The 599 engine runs like a top with the DB-2. I set the timing using a snap-on MT-257 transducer-style timing adapter. My initial timing is 5 degrees BTDC. The response of the DB-2 pump is awesome. When you call for fuel, -you get it. The turbo response is lightning-fast with the mechanical pump. As far as fuel rate goes, -well, not quite as much as I had hoped for, -but the driveability with the cable-controlled IP is much better than the fly-by-wire DS-4, -I ain't lookin' back.

So, the ending to this long story, -the engine has 600 miles logged on it since the build, and runs like a swiss watch. Power is excellent. EGT's are right close to 1000F (pre-turbo) with all the coal on the fire (at 15 PSI). The static CR came out to around 19:1, -which in my opinion is a good compromise. Cold starts aren't a problem, -a little smokier than the 21:1 was, -but not too bad. After 10 seconds at 50F, she smoothes out and cleans up nicely. The best part is the 19+ mpg it's getting.

I love this new motor, -and I hope the studs do the trick. Just driving the truck around for the last two weeks or so has reminded me why I relentlessly plowed through this project from the very beginning. These trucks just drive so nice, -and are roomy and comfortable. And now, I can start catching up on getting all the stuff done that I've needed a truck for (but been without), for the last year.......

Another happy 6.5'er!

 

[NVW]

It's always more entertaining to read about it:agreed:

 

[Ratman]

I sorta feel like I hijacked this thread, -I apologize.

The same 599 build is running, -with a quirky DB2, -and losing about a cup of coolant a week, -no biggie really. The thing still runs great, -always starts, -get's mediocre fuel economy with my GM4 wastegate tied shut, -is coming up on 40k+ miles, -and I sure don't baby the thing. The governor in the DB2 has been misbehaving for almost a year, -and the damn thing sometimes shoots well past 4500 RPM, -but it just keeps running, -and is RELIABLE.

I'm no expert on these diesel rat-motors by any means (I'm gonna catch some flack for that!), -but it's awefully hard to keep a straight face when a powerstroke guy follows you into a parking lot with his 7.3 IDI and starts asking all kinds of questions about how in the heck I laid such a big patch of rubber at an intersection, -and I try to explain that the injection pump is misbehaving and such...:hihi:

It surely isn't the quickest rig on the road, -but it does catch people by surprise from time to time, -and she's still running great.

 

[DieselSlug]

I remember reading that thread. Made me soo nervous when i fired mine up for the first time. I think it took me a day just to check everything over before i got the guts to start mine... Love the Camaro, good luck and cant wait to see the next build!

 

[Ratman]

I remember reading that thread. Made me soo nervous when i fired mine up for the first time. I think it took me a day just to check everything over before i got the guts to start mine... Love the Camaro, good luck and cant wait to see the next build!

You can imagine the hair standing up on the back of my neck after what happened. I swear, I was afraid to even touch the damn ignition switch on the steering column after what happened. After I put the 599 together, it literally took months before I relaxed and started actually "driving it" like it should be driven.

I pu$$y-footed the second build for a couple of months before I nutted-up and actually turned it past 2000 RPM, -no lie.

Now it's all or nuthin' at all.. She's still together, -and runs good, -something must be right.

 

[SCREAMINXL]

Thanks for getting me up to speed.

 

[Ratman]

Thanks for getting me up to speed.

Well, it's kind of a horror-story, but now you know...

 

[3500GMC]

I sure would like to see the post-mortem inside Cody's Camaro engine.

Morbid curiosity, that's all.