Careless Posted September 23, 2007 Share Posted September 23, 2007 Yeah, you read that title. Even though it's not that common, I think I've discovered a crack in my main journal web casting, or just a weak casting from the get go. I'm at my parent's house, but at home I have it on digital camera. I'll post them later, but I'm just making this post so that I can sleep well tonight. LOL Basically what I was doing was grinding the flashing down off my main journal webbings, just as one would when finishing a set of stock SBC cast connecting rods. Some say it doesn't do anything cause RB blocks are monsters, but hey, I like to do stuff that makes me feel good, ok? When I got to the main journal that holds the thrust washer in place, I noticed that JUST under the oil pickup tube location, there are a pair of what SEEMS to be cracks. But, I THINK it is a casting issue, and I'm wondering if the RB30's all have this problem. Now, my previous builder said he checked for cracks and he also hot tanked it... But yah, he hot tanked it in some environmentally friendly stuff that can't even strip soap from sink, and he also left the casting plugs and all that removable stuff in there. So I don't trust him with the magnifluxing. I am taking it to someone else, but since I had it at home I decided HEY LETS WORK ON IT first. So I get to this area, and it's got a valley that runs from the top of the webbing, around the inside of the block, and passed the cylinder and then halfway back up. I don't know what to think, and I can only hope that the pictures came out good. I mean, I AM going to radius those valleys as best as I can so that they don't actually crack... but being on the thrust bearing webbing, it's a big concern. Is this common on the RB30 castings? I'm going to re-dip the block and have it checked for cracks again, but I'm not going to mention anything to the machinist this time, to see if he can spot it. If he doesn't I'm going to look elsewhere. My idea with that crack is that if he says "well there was a slight casting issue on the middle webbing, but I think it will be ok", then chances are i'll leave my engine there and have him do the machine work. But if he doesn't even mention it, i'd be curious to know if he really does care about the outcome of this engine or if he wants to see his customers come back later with a new project to spend money on. I'm worried guys, make me feel good Quote Link to comment Share on other sites More sharing options...
Careless Posted September 24, 2007 Author Share Posted September 24, 2007 So, Here's what I'm talking about. The picture below is a detailed shot of what I was doign when I discovered this. On the left we have the deburred main-tower. It's not complete (has to be slightly radiused at the sides), but the top and bottom near the main girdle seat and the oil-pan mounting surface has been ground out already as well (not shown in the picture, but it's done). The area near the main-girdle mounting surface was carefully done so as to not ruin the good interference fit these girdles have. The interference fit can always be re-tightened by getting a cold-steel chisel and giving it a firm pop when the girdle is in place, and bolted down (before final assembly, or any align honing). This usually tightens the metal upto the girdle, but must be done carefully enough so that it doesnt shift the girdle out of place. Just a light tap to squish the metal a bit. Anything hard and you'll crack it, or warp the interference fit. Ignore the rust. That's what you get when an "engine builder" claims to be a machinist, and uses improper practices to clean and prep a block. Quote Link to comment Share on other sites More sharing options...
Stealth-Z Posted September 24, 2007 Share Posted September 24, 2007 Just went to the garage to look at mine. Yours look like it might have been a weak casting possibly? All the flashings around mine smoothed up well. There were no crack-like appearances. I was going to take a picture for you but the camera's battery is dead. Takes some time grinding the flashings doesn't it? I forget how many hours were spent on mine. Quote Link to comment Share on other sites More sharing options...
Careless Posted September 24, 2007 Author Share Posted September 24, 2007 took me about an hour and a half to do all the main girdles. I dunno if i should put money into this thing. has anyone with similar blocks had bad experiences? =( Grinding was fun though. Quote Link to comment Share on other sites More sharing options...
Careless Posted September 24, 2007 Author Share Posted September 24, 2007 I can still get another block from the same guy. He said I can exchange it. Hmmmmmm... Quote Link to comment Share on other sites More sharing options...
Careless Posted September 24, 2007 Author Share Posted September 24, 2007 still searchin' for hope of good news :'( Quote Link to comment Share on other sites More sharing options...
Evan Purple240zt Posted September 24, 2007 Share Posted September 24, 2007 Looks like janky casting. Why not just have it fixed? There has to be someone who can weld that right? It would be worth a little money not to have to redo all your nice grinding work. Evan Quote Link to comment Share on other sites More sharing options...
Careless Posted September 24, 2007 Author Share Posted September 24, 2007 Looks like janky casting. Why not just have it fixed? There has to be someone who can weld that right? It would be worth a little money not to have to redo all your nice grinding work. Evan I'm not sure of the integrity beneath that bubbley casting area just beneath the crack. And thanks for the compliments on the grinding, but I enjoyed doing it =) I actually wouldn't mind doing it again. Gives my our huge air compressor a work out though. I think next time I'll take it slower and do 3 journals, and rest the compressor for an hour. damn 90 gal can't even keep up. Quote Link to comment Share on other sites More sharing options...
Careless Posted September 24, 2007 Author Share Posted September 24, 2007 So I've talked to the engine importer and he said I can pick up another block, but they've been transported to a warehouse quite far from where I live (not too far, but have to spend a good portion of a night going there). I'm surprised something like that passes quality control, seeing as the casting is almost connected across the entire main skirt Quote Link to comment Share on other sites More sharing options...
stony Posted September 24, 2007 Share Posted September 24, 2007 OUCH is that actually a crack or the casting. the shadow makes that look like a HUGE crack. I would think you would have seen some type of abnormal wear or failure somewhere else with something that big!!!! Quote Link to comment Share on other sites More sharing options...
Careless Posted September 24, 2007 Author Share Posted September 24, 2007 OUCH is that actually a crack or the casting. the shadow makes that look like a HUGE crack. I would think you would have seen some type of abnormal wear or failure somewhere else with something that big!!!! No shadow here, stony. I can put my finger nail into it. I had not even looked at the skirts because I was concentrating on the ones I was grinding. Then I left that one for second last (oddly enough), and it's poorly casted. I'm pretty sure it was a downright bad casting, due to the fact that there's a funny looking area just to the left of the upside down "2" casting. It looks as if molten iron had dripped and burst the cast somehow, or caused it to run and sag just a touch. its as if the entire journal slumped a mm or so, and it was evened out during the main journal grinding. I'm not going to use this block for anything but practice.... but hey, now I have a block to use for engine mounting in bay while I build mine over the winter unless I have to give it back. In that case I'll offer up what I think it would fetch at the scrappers (30 bucks probably), as I think it's a good idea to use it so that my real engine doesnt get dinged and dropped and such. And because it's much easier to move with just the oil pan on it than with the crank and rods and all that in there. Quote Link to comment Share on other sites More sharing options...
Careless Posted September 24, 2007 Author Share Posted September 24, 2007 BUT WOULD'JA LOOK AT THAT GRINDING I DID ON THAT FIRST JOURNAL GAH'DAYYYUM. hahah, finding a reason to keep myself happy sorta sucks but it's all the fun I got Quote Link to comment Share on other sites More sharing options...
Evan Purple240zt Posted September 24, 2007 Share Posted September 24, 2007 Well just be glad your importer didn't tell you to piss off. Not having that stuff will make mockup much easier. I did mine with no crank in the block. Made it a bit lighter. When I did my L28 build, I mocked up with no internals. Evan Quote Link to comment Share on other sites More sharing options...
Careless Posted October 2, 2007 Author Share Posted October 2, 2007 Got a new block. Gave my importer/friend Ted 65 bucks for his time because his engine blew up recently and he's strapped, and we had a fun 4 hour trip (2 forth and back). Had some laughs, jokes, the whole bit. ♥♥♥♥♥♥♥ things are way heavy. LOL. I forgot how heavy they were when I first lifted it. Looks like it's time to install a telescoping crane in the scrap-metal hauler Toyo Previa. Wish me luck, gents! gonna try and rip her open tomorrow! Quote Link to comment Share on other sites More sharing options...
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