wayno Posted April 28, 2011 Report Share Posted April 28, 2011 Ok, the short block went to the machine shop two saterdays ago, I went there this evening and asked about it and I was told the deck had a crack in it, the cracks actually are drivers side center head bolt hole going frowards and backwards into the water jacket. Is this going to be a problem? It is the only hole with the cracks, is this block scrap? Quote Link to comment
metalmonkey47 Posted April 28, 2011 Report Share Posted April 28, 2011 Got pictures by chance? Depending on how bad they are, I would say it may not be worth screwing with. Quote Link to comment
wayno Posted April 28, 2011 Author Report Share Posted April 28, 2011 Got pictures by chance? Depending on how bad they are, I would say it may not be worth screwing with. I will try to get a photo tomarrow, I did not have the camera with me. I bet this is a comman issue with these blocks, but does it make them scrap? Quote Link to comment
metalmonkey47 Posted April 28, 2011 Report Share Posted April 28, 2011 I will try to get a photo tomarrow, I did not have the camera with me. I bet this is a comman issue with these blocks, but does it make them scrap? Probably not scrap, but since the cracks are already affecting the water jacket, do you really wanna risk building an engine that may just be a dud in the future? As cheap as Z blocks are, it may just make more sense to look for a new block. Just my 2 cents though. Quote Link to comment
izzo Posted April 28, 2011 Report Share Posted April 28, 2011 Its common for small cracks, normally around water jackets i thought? Even so, it should be fine for what you are doing. In a race application you would discard of it and find something else, but for street use it should be fine. Get some photos when you can so we can see what the crack looks like. And by small crack, i mean super small. not any major cracking :D Quote Link to comment
Sealik Posted April 28, 2011 Report Share Posted April 28, 2011 I don't think I would dump any money into a cracked block. Also....some Z blocks are cheap.....but...not easy to find a low mile Z22 in good shape Quote Link to comment
wayno Posted April 28, 2011 Author Report Share Posted April 28, 2011 That particular headbolt hole is surrounded by water jacket and the exterior of the block, the oil supply port is on the other side. Z22 blocks are around, but they are long blocks, and no one wants to remove the head so I can take a look at the deck. As far as I know, they could all be cracked there, like the SD22 heads, and I don't have the money to be paying that price for scrap metal. Does anybody in the portland or. area have a good Z22 core to sell? Quote Link to comment
datzenmike Posted April 28, 2011 Report Share Posted April 28, 2011 http://community.ratsun.net/topic/25243-ka-z24-build-compression-questions-done/page__st__40 I bet there are a lot on engines out there with various cracks in them leading normal lives. It sounds ominous but a crack is a stress reliever. If the gasket is doing it's job nothing is going anywhere. This isn' t a reciprocating part at 6K and 120 hp or anything!! Quote Link to comment
wayno Posted April 28, 2011 Author Report Share Posted April 28, 2011 http://community.rat...ne/page__st__40 I bet there are a lot on engines out there with various cracks in them leading normal lives. It sounds ominous but a crack is a stress reliever. If the gasket is doing it's job nothing is going anywhere. This isn' t a reciprocating part at 6K and 120 hp or anything!! Ok Datzenmike, I went threw that section of thread and copyed this photo, in the center head bolt hole I have cracks that go directly to the right and left in the photo below into the water jacket, I have no cracks going towards the cylinders themselves or the water jacket hole above the headbolt in the photo below. I have no problem seeing the cracks with my readers on though. I will try to get a oic. tomarrow. Does it do any good to weld these cracks at all? In this photo the surface is welded, but what about the water jacket part? Quote Link to comment
wayno Posted April 28, 2011 Author Report Share Posted April 28, 2011 So here are the cracks in the block deck, they are the only ones. Quote Link to comment
izzo Posted April 29, 2011 Report Share Posted April 29, 2011 I wouldn't worry about those tiny cracks. I see they marked it as a z24. does it have a different bore? Quote Link to comment
wayno Posted April 29, 2011 Author Report Share Posted April 29, 2011 I wouldn't worry about those tiny cracks. I see they marked it as a z24. does it have a different bore? That was a note the machinist put on there to himself, as I told him I wanted Z24 pistons put in the block, you can also see that it says 89mm, as that is what the Z24 piston is supposed to be. I am hoping that there is not more than one type of Z24 piston, you know, S, E, Fi, ect. Quote Link to comment
datzenmike Posted April 29, 2011 Report Share Posted April 29, 2011 The machinist should have the pistons to bore to match them. 89mm is approximate. The '84 720 FSM states that factory pistons range in size from 88.956mm to 89.015mm so you can see that if your block is bored to exactly 89mm some stock pistons won't fit, some will be too tight while others will be too loose. The Z24 motor is a truck only motor and the pistons did not change as far as I know. The Z24 came with carb, electric feedback carb and throttle body injection. Pistons were the same AFAIK Quote Link to comment
wayno Posted April 29, 2011 Author Report Share Posted April 29, 2011 The machinist should have the pistons to bore to match them. 89mm is approximate. The '84 720 FSM states that factory pistons range in size from 88.956mm to 89.015mm so you can see that if your block is bored to exactly 89mm some stock pistons won't fit, some will be too tight while others will be too loose. The Z24 motor is a truck only motor and the pistons did not change as far as I know. The Z24 came with carb, electric feedback carb and throttle body injection. Pistons were the same AFAIK He told me that he would order the pistons as soon as I called him about the cracks, he didn't seem to think the cracks were that bad for a DD, until I told him the engine was going in the work truck, then he looked at me with that look, you know the look, the isn't it about time you got a dodge diesel look, I gave him the, I have been using the rig the way it is** since gas went above $3.00 a gallon, i'm not changing now answer/look. :lol: ** Have upgraded the front brakes, steering, rear axle, rear suspension, transmission, ect. So I have one opinion on the cracks, anymore? Quote Link to comment
datzenmike Posted April 29, 2011 Report Share Posted April 29, 2011 New pistons! No problem then. Quote Link to comment
yello620 Posted April 29, 2011 Report Share Posted April 29, 2011 Is that block for sale if you choose not to use it? I would not hesitate to do a basic rebuild/bore on that block. I would not make a high rpm race motor out of it. Quote Link to comment
metalmonkey47 Posted April 29, 2011 Report Share Posted April 29, 2011 It's not as bad as I thought it was. I'd run it. Those are just minor stress cracks.. Quote Link to comment
wayno Posted April 29, 2011 Author Report Share Posted April 29, 2011 Is that block for sale if you choose not to use it? I would not hesitate to do a basic rebuild/bore on that block. I would not make a high rpm race motor out of it. I am planning on using the block now, sometimes though, the way I drive/use the truck, it would seem like I beat it worse than a race motor, but all the beatings take place below 4500rpm. Quote Link to comment
hang_510 Posted May 7, 2011 Report Share Posted May 7, 2011 i have the exact same cracks on mine. i gave up trying to find an uncracked block (L20 or Z22) the return to canby will be 1 year, hard running. So I have one opinion on the cracks, anymore? crack stains! Quote Link to comment
wayno Posted May 7, 2011 Author Report Share Posted May 7, 2011 The Z24 pistons were ordered last week, I check in every week or so, it's kind of cool to drop in and see what the guy is working on that day, last week he had a 4 cyl. block in there that had quit a large bore, but a very short stroke, my guess would be, the engine was at home at very high RPMs. Quote Link to comment
wayno Posted May 18, 2011 Author Report Share Posted May 18, 2011 I stopped in at the machine shop today, got a look at the shiny new pistons, he miked them and they were all the same size, he said, that piston suppier was a really good one with high quality products and they never sent him anything that wasn't uniform. The block has already been bored to the pistons, he just has to find the time to put the short block together, I am going to let him put the short block together, as I know it will be right, I will put the head on and eveything else. Now I have to find a head gasket and figure out if any holes will have to be drilled in the block for/as coolant passages. I have my W53 super head to put on this LZ22 block. Quote Link to comment
Sealik Posted May 18, 2011 Report Share Posted May 18, 2011 Depending on the head..(pic?)...there should be 7 in block....9 in HG That config is for the U67 W53 Looks like you should be drilling the same amount Quote Link to comment
sinner720st Posted May 18, 2011 Report Share Posted May 18, 2011 The Z24 pistons were ordered last week, I check in every week or so, it's kind of cool to drop in and see what the guy is working on that day, last week he had a 4 cyl. block in there that had quit a large bore, but a very short stroke, my guess would be, the engine was at home at very high RPMs. Damn.... you should have ordered some ka24 single cam piston instead. it would have given you higher compresion. although you will probably get some good compresion out of an L head Quote Link to comment
wayno Posted May 18, 2011 Author Report Share Posted May 18, 2011 Damn.... you should have ordered some ka24 single cam piston instead. it would have given you higher compresion. although you will probably get some good compresion out of an L head I am supposed to have somewhere around 8.9 to 1 CR. I have a W53 closed chamber head with super sized valves, and the intake is ported to match the dual SU intake manifold. Quote Link to comment
Stoffregen Motorsports Posted May 20, 2011 Report Share Posted May 20, 2011 I wouldn't worry about those tiny cracks. I would! Don't waste your money building a cracked block. You could always "franken-block" it. Grind the ID area flat and drill and tap the holes to take a couple of 10-32 screws. Counterbore the outer half of the crack. Install the screws with Threebond 1211 sealer on them and use the same (or pipe dope) on the head bolt threads. Ask Cody about the franken-block. Quote Link to comment
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