Disassembly of a 69 Z/28 DZ Three Oh Blew Engine

[SuperNovaSS]

I realize I have not been sharing here as much as I used to and am going to try to start posting more often.

I buy complete muscle car engines that have been sitting dormant for long periods of time pretty often. Sometimes they are engines that were pulled out of running cars or boats, others were pulled from non running cars, and the gambles were pulled to to sudden death. Sudden death is the case with the engine I am sharing with you today.

This is a 69 Camaro Z/28 "DZ 302" engine that was pulled from a 69 Z/28 after some enthusiastic tuning sessions. As you can see by the oil pan, the high revving mouse engine was likely pushed a bit further than designed. This was the cause of death for many early Z/28 engines. Like a kid eating cake, the engine keeps asking for more but eventually it is going to have to puke!

This engine was in a true 69 Z/28 but was not the VIN matching engine for the car. After "tuning" this engine, the owner decided to build a new engine for the car from scratch, taking items off this engine like the pulleys, etc. This engine was put on a dolly and put in the corner of the garage without ever being opened up to evaluate the damage. The owner decided to sell the engine recently and I could not resist seeing what was inside.


http://i179.photobucket.com/albums/w301/super-novass/IMG_9669_zps8bfd4bd9.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9669_zps8bfd4bd9.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9668_zps7e1f4b99.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9668_zps7e1f4b99.jpg.html)


http://i179.photobucket.com/albums/w301/super-novass/IMG_9677_zps17410e9d.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9677_zps17410e9d.jpg.html)


http://i179.photobucket.com/albums/w301/super-novass/IMG_9676_zpsed4e7707.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9676_zpsed4e7707.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9675_zps8f751134.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9675_zps8f751134.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9671_zps8012db3a.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9671_zps8012db3a.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9680_zps0ea91207.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9680_zps0ea91207.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9679_zpsef8686fd.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9679_zpsef8686fd.jpg.html)



Looking at the numbers, the engine began life as a true DZ 302 and had likely been tinkered with in the past. I say this because the block has a March 69 casting date and assembly code but the heads are dated August 1968. I imagine the top end was original to the Z/28 the engine was installed in and the shortblock was replaced at some point. That is just an assumption though, the heads on the engine could be off of anything and could even have the smaller 1.94/1.50 valves. It is reasonable to assume if the engine has been apart than it has likely been bored and possibly had other work done. Other evidence that this engine has been apart include a later model timing cover and later model valve covers with drippers(69 were non dripper).

The only way to find out is to dig in and get dirty........

[SuperNovaSS]

Here is the oil pan, one side has multiple dents from something trying to escape and there is only one spot on the other side:

http://i179.photobucket.com/albums/w301/super-novass/IMG_9678_zpscf2bf644.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9678_zpscf2bf644.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9666_zps5cfef8c4.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9666_zps5cfef8c4.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9664_zpsf1d3585b.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9664_zpsf1d3585b.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9667_zpsf9a1ff18.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9667_zpsf9a1ff18.jpg.html)


While the little oil that is the pan is draining, let's check out the top end:

http://i179.photobucket.com/albums/w301/super-novass/IMG_9663_zps2cc6ca76.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9663_zps2cc6ca76.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9683_zpse3d6b505.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9683_zpse3d6b505.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9681_zps8db5a089.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9681_zps8db5a089.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9682_zps4281e60a.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9682_zps4281e60a.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9684_zps163cfacf.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9684_zps163cfacf.jpg.html)


Hmmmmm, where did those pushrods disappear to? Let's check under the intake:


http://i179.photobucket.com/albums/w301/super-novass/IMG_9685_zpsd80dd00f.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9685_zpsd80dd00f.jpg.html)

No, I did not remove that lifter. If that is not strange enough, where are the 2 missing lifters????

Oh, there is one. I wonder how that got down there?

http://i179.photobucket.com/albums/w301/super-novass/IMG_9686_zps3d73fbac.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9686_zps3d73fbac.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9687_zps50305196.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9687_zps50305196.jpg.html)


The oil is still draining. We might as well pull the heads. I want to see if they are 2.02/1.60 valves anyway.

http://i179.photobucket.com/albums/w301/super-novass/IMG_9695_zps03176d4d.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9695_zps03176d4d.jpg.html)


http://i179.photobucket.com/albums/w301/super-novass/IMG_9690_zpsafc295f7.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9690_zpsafc295f7.jpg.html)

Looks dirty but not bad at first glance. I don't see any stampings on the pistons. Could this possibly be standard bore?

One piston looks to be sitting a bit high and has a nick in it.

http://i179.photobucket.com/albums/w301/super-novass/IMG_9691_zpsc6d251c7.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9691_zpsc6d251c7.jpg.html)

Let's check the head on that cylinder:


http://i179.photobucket.com/albums/w301/super-novass/IMG_9693_zps8f56d3ea.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9693_zps8f56d3ea.jpg.html)

The good news is the heads are factory high performance units with 2.02/1.60 valves and no modifications like porting or screw in studs. The bad new is one intake valve is bent from that piston. Not a big deal.

OK, the oil has stopped draining out of the pan. We know there is carnage down there. Want to check it out? I do.



http://i179.photobucket.com/albums/w301/super-novass/IMG_9696_zpsc62c6e1d.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9696_zpsc62c6e1d.jpg.html)


http://i179.photobucket.com/albums/w301/super-novass/IMG_9697_zpsafdb666b.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9697_zpsafdb666b.jpg.html)


Hey, there is the missing pushrod! Amazingly, it is still straight!

I don't think we can straighten the windage tray. But we did find the other lifter. Notice anything missing from the crankshaft?


http://i179.photobucket.com/albums/w301/super-novass/IMG_9699_zps02905fbb.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9699_zps02905fbb.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9698_zps80021751.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9698_zps80021751.jpg.html)

[SuperNovaSS]

Yep, we seem to have misplaced a rod.

http://i179.photobucket.com/albums/w301/super-novass/IMG_9700_zps8b4e6a63.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9700_zps8b4e6a63.jpg.html)


Oh, there is part of it in the next bank:

http://i179.photobucket.com/albums/w301/super-novass/IMG_9703_zps252398cf.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9703_zps252398cf.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9701_zpsca7a52e9.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9701_zpsca7a52e9.jpg.html)



GM part number on the bottom of the TRW pistons. This block is standard bore. The question is, can it be saved?

http://i179.photobucket.com/albums/w301/super-novass/IMG_9701_zpsca7a52e9.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9701_zpsca7a52e9.jpg.html)


Look what I found, that explains the magic disappearing lifters:


http://i179.photobucket.com/albums/w301/super-novass/IMG_9710_zps512715f9.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9710_zps512715f9.jpg.html)


Time to dig deeper, let's get the rods and pistons out:

http://i179.photobucket.com/albums/w301/super-novass/IMG_9711_zpsdc0f2d9f.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9711_zpsdc0f2d9f.jpg.html)


.001 under rod bearings. Uncut rod journals. Unfortunately that was that was rodless needs some attention:

http://i179.photobucket.com/albums/w301/super-novass/IMG_9709_zps737df828.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9709_zps737df828.jpg.html)


http://i179.photobucket.com/albums/w301/super-novass/IMG_9714_zps7c51ed0c.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9714_zps7c51ed0c.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9713_zpsd31952a2.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9713_zpsd31952a2.jpg.html)

Hmmm, to much tuning:

http://i179.photobucket.com/albums/w301/super-novass/IMG_9708_zps0d109939.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9708_zps0d109939.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9707_zps7a09986f.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9707_zps7a09986f.jpg.html)

Let's get that crank out so we can see how this block looks:

http://i179.photobucket.com/albums/w301/super-novass/IMG_9719_zps9d64847f.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9719_zps9d64847f.jpg.html)

[SuperNovaSS]

Well, there is damage to the bottom of the cylinders but nothing I see in the ring areas:

http://i179.photobucket.com/albums/w301/super-novass/IMG_9720_zpsc0fb7189.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9720_zpsc0fb7189.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9721_zps5a675d19.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9721_zps5a675d19.jpg.html)


Oh wait, is that a........ damn it:

http://i179.photobucket.com/albums/w301/super-novass/IMG_9723_zps6f9108f4.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9723_zps6f9108f4.jpg.html)


And another in the next cylinder:

http://i179.photobucket.com/albums/w301/super-novass/IMG_9728_zps675eba13.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9728_zps675eba13.jpg.html)

It may still be repairable with 2 sleeves. It will have to go to the machine shop to be cleaned and checked for other unseen cracks.


Lets get that cam out:

http://i179.photobucket.com/albums/w301/super-novass/IMG_9715_zps73994dfb.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9715_zps73994dfb.jpg.html)


It looks like the last time the engine was messed with was the early 90's bases on the cam sprocket:

http://i179.photobucket.com/albums/w301/super-novass/IMG_9716_zpse866731f.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9716_zpse866731f.jpg.html)

Alright, we got the cam out!


http://i179.photobucket.com/albums/w301/super-novass/IMG_9729_zps26166f82.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9729_zps26166f82.jpg.html)


OK, we did it! No exactly what we were hoping for but that's the way the cards fall. If you guys are interested in the outcome, I will let you know when I hear from the machine shop.


Thanks for looking,

Jason

[ss427copo]

Two words: Boat Anchor.

[Salvatore]

Good job Jason!

[300deluxeL79]

love this engine stuff, keep it comin! <<GRAEMLIN_URL>>/biggthumpup.gif

[earntaz]

Took me a few minutes to check all the battle damage which I might add occurred in a heart beat ... good pictures Jason!!

[ds1]

Looks like the one Crack goes to the head bolt. But not a big deal. Two sleeves and a Threadsert and it's back in play. Comes down to how bad someone wants an OE engine. But then you already know that. The rod broke and hit the cam.

[green crv]

Wow, that was good suspends, bad ending thought. Gives new meaning to big cam sound lol. <<GRAEMLIN_URL>>/biggthumpup.gif

[resto4u]

If you don't have a crack in the cam section and just two sleeves, save it.

[PxTx]

http://i710.photobucket.com/albums/ww101/Plowman7/2014-12-16%2019.54.16_zpseb5ftjuh.png (http://s710.photobucket.com/user/Plowman7/media/2014-12-16%2019.54.16_zpseb5ftjuh.png.html)


This scares me from considering trying to save it. Sorry for the phone edited pic. Thanks for sharing Jason.

[enio45]

stock cam??

[SuperNovaSS]

Thanks for the replies guys. I didn't see any stampings on the cam. I believe it was a stock replacement. I believe a threadsert in the cracked threads along with the sleeves should fix the problem you are pointing out. I have had blocks that were good runners for a long time with that type of repair. It is lifter valley, cam journal, and main area cracks that I could not see that would make this block junk. I agree this block would be a boat anchor already if it was most any other application. Can you imagine how many other DZ blocks with less damage were tossed out since it was just a 4 inch bore 4 bolt block?


Jason

[enio45]

nice write up and tutorial :-)

thanks for taking the time to do this

[SuperNovaSS]

My pleasure. As I said, I plan to do more soon. Hopefully some media blasting tutorials since the blasting cabinet is a good place to hide of the rain <<GRAEMLIN_URL>>/smile.gif


Jason

[ds1]

400 block decks Crack all the time. My best runner had several cracks. The machine shop was not concerned. The Threadsert will go in first and make the deck stable. Then the sleeves will take care of the cylinders. My brothers 73 Corvette had the worst block casting I have seen. It was porus. Looked like black pepper down inside it. When he rebuilt it and torqued the heads all the bolts on the driver side top of the deck pulled out. But it was the OE engine so all the holes were helicoiled and found one of the cylinders cracked. Sleeved the bad cylinder and rehoned the adjacent cylinders because of shift. Way to much work for a two bolt main 350. But the original for his car, number matching.

[69z28302]

Love this stuff. Let's hope it's salvageable

[Plowman]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: pxtx</div><div class="ubbcode-body">http://i710.photobucket.com/albums/ww101/Plowman7/2014-12-16%2019.54.16_zpseb5ftjuh.png (http://s710.photobucket.com/user/Plowman7/media/2014-12-16%2019.54.16_zpseb5ftjuh.png.html)


This scares me from considering trying to save it. Sorry for the phone edited pic. Thanks for sharing Jason. </div></div>***Damage produced when something is dented.

[njsteve]

I like that camshaft photo. Looks like the prototype camshaft for the infamous GM V8-6-4 that Cadillac used. <<GRAEMLIN_URL>>/naughty.gif

[Dusk Blue Z]

Hi Jason,

I was trying hard to read the assembly date on the front pad, is it a 03 or 05?. Has the block been lightly fly cut? Is there a LOS vin stamped on there too? Thanks.

Mike

[Lynn]

03

[SuperNovaSS]

Yes, the block was lightly surfaced at some point. The assembly code is V0321DZ and the partial VIN is 19L528983.

http://i179.photobucket.com/albums/w301/super-novass/IMG_9730_zps52666bc2.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9730_zps52666bc2.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9733_zpse9eef8ff.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9733_zpse9eef8ff.jpg.html)

[tom406]

Check out the giant 2. So goofy you know it's real;)

[miket1]

It can most likely be repaired, nice show.

[resto4u]

yeah, that guy had a bad day and grabbed the wrong stamp into the gang holder. I have seen a few oddities on los engines. have see one where they mix up the partial vin# order and put the L first, then year and vin#

[427TJ]

Yep, they're still out there! Still gettin' blowed-up too!

[Day2_69Z]

Oh,,, don't look soo bad....
Looks like an EBay engine Joe Billy Bob Rebuilding service sells as great condition, complete , standard , just needs an overhaul kit and assembly.....feed back -09 37%......

I may be embellishing this scenario, but a lot of us have seen similar ads in media &amp; i-net and have chased the leads to similar results......The seller assumed the worse I hope as Jason hoped for the best.......
Awesome post Jason along with nice pics ..
other than the rod journal damage it looks like a few counterweights are damaged....Yes, No, Maybe ?

[SuperNovaSS]

The counterweights have a few nicks but nothing catastrophic. The seller actually expected no damage to the block or crank. We came up with 2 prices. One price was higher and came with a unwind clause if there was damage and the other was as is. I am a gambler and went with the as is. The internals could have been much worse in my opinion. Thanks for all the replies guys. I am going to do another post soon about media blasting.


Jason

[Day2_69Z]

. The seller actually expected no damage to the block or crank.

Jason[/quote]

Jason, I'm sorry but I can't stop laughing at the sellers expectations especially as I look at the pan ..... he must of been the one that didn't change the oil or have the timing set nor the valves set not even to say why
in the hell would you rpm a high revving motor Without Screw in studs ,or let alone pinning them.....Who ever blew it up EARNED that Pleasure of hearing how mechanical catastrophic pleasure sounds..... <<GRAEMLIN_URL>>/crazy.gif

This had to been locked up and I bet overheated, I wonder how tight the rod bolts were when you untorqued them for removal....
still laughing but now at myself knowing the former owner of my Z/28 blew it up &quot;way better&quot; than yours.
The motor was already heavily worked on the drag strip, street and road racing.....sleeved in 4 cylinders, line bored twice, maybe 3 times before and only decked 4-5 thousaths.....roller cam with gear drive on a street n strip car, not a good idea.
Needless to say, anything that can happen to an engine blowing up happened to this lil 302...It Grenaded !
with only the top end and externals salvaged....... funny but not that funny when it happens to your own stuff.....

Tom

[Dave Rifkin]

Is that crankshaft salvageable; looks pretty beat up.

[SuperNovaSS]

Believe it or not, the engine did spin free after it blew up. I did not try to spin it when I bought it.

As far as the crank goes, the jury is still out. It depends if it is cracked. The mag powder doesn't lie.

Jason

[earntaz]

Absolutely crack check! And don't believe the theory of stand it on a rag and tap with a hammer to get a good &quot;ring&quot; ... UGH!!!

[427TJ]

R.I.P. Rest In Pieces.

[69SSZL1]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: SuperNovaSS</div><div class="ubbcode-body">Yes, the block was lightly surfaced at some point. The assembly code is V0321DZ and the partial VIN is 19L528983.

http://i179.photobucket.com/albums/w301/super-novass/IMG_9730_zps52666bc2.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9730_zps52666bc2.jpg.html)

http://i179.photobucket.com/albums/w301/super-novass/IMG_9733_zpse9eef8ff.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9733_zpse9eef8ff.jpg.html)



</div></div>

My friend's RS Z/28 has the same large 2 in the VIN stamp, a few hundred from yours. You need to save that motor! Check out this VIN stamping, it is the same on the M22 also. What happens is a stamp will break and they will just grab another one:

http://www.yenko.net/ubbthreads/pics/usergals/2014/12/full-2154-19739-vinandenginestamps052.jpg

[BJCHEV396]

Good stuff Jason.Very informative and interesting!

[69VN]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: ss427copo</div><div class="ubbcode-body">Two words: Boat Anchor. </div></div>

<<GRAEMLIN_URL>>/haha.gif

[SuperNovaSS]

Hey guys,


I thought I would just give an update for those following this thread.

The block came back from the machine shop with the only cracks being in the 2 cylinders I showed in the pictures. It is fixable and is being sent to Australia along with the oil pan which will be installed in a real Z/28 with a very close VIN.

The intake went to Australia to be installed on yet another Z.

The heads had no damage other than the one bent valve and have gone to the South where they will bring another Z/28 a little closer to correctness.

The crank was found to have no cracks so it was sent to Engine Warehouse in Sacramento, CA to be checked, welded, and turned. It came back a few days ago and looks awesome. It cleaned up at 10/10.



Jason

[scuncio]

Cool, glad you could save it. Why did you weld the crank?

[SuperNovaSS]

The journal got a bit beat up by the rod:

http://i179.photobucket.com/albums/w301/super-novass/IMG_9713_zpsd31952a2.jpg (http://s179.photobucket.com/user/super-novass/media/IMG_9713_zpsd31952a2.jpg.html)

[Bill Pritchard]

Yep, it would take a bit more than a .010&quot; cut to clean that up without welding!