Tossed a rod out of the front of my zx10 motor. It looks like it came out on the down stroke and didn’t damage a whole lot besides the obvious hole, is there anyone on the east coast that would possibly try to weld back up the cases if they’re not too damaged otherwise?
I’ve bore scoped it and it seems like con rod bolts went, crank came around and whacked it into the case, and slightly damaged the bottom of the cylinder. Piston hopefully didn’t hit the head, so besides the hole and bottom of the cylinder needing repair, it could be as simple as the cases and cylinder being welded up, and replating the one cylinder. I have a spare motor sitting at home, so this isn’t something I need fixed asap, as long as it isn’t too cost prohibitive to repair.
I've never seen a modern four cylinder case with a rod penetration that was worth repairing, let alone one I would be willing to ride at 14K rpm. It's likely that the sudden momentary deceleration of the crank did other things besides hole the case.
Bummer, hopefully the crank is repairable and head survived at least then, and I can pick up new cases in the near future.
I like to fix things if they can be fixed versus throwing them out, and I’ve seen welding done on dirt bike cases so I thought it would be plausible. I also thought that welding the cases, replating the one cylinder, and having the crank journal repaired would come in at, or under the price of a used motor of questionable history, since everything else in it was relatively fresh.
You are not going to be able to replate just one cylinder. They have to do all four, cases are acid stripped, replated, bored. honed. If you don't completely strip the parts in the cases yourself, you have to pay the plater to do it, then reinstall all the various parts properly. Welding cases is sometimes sketchy because you often boil oil out of the porous casting and contaminate the weld, can take some effort. It's common that metal debris from the incident has damaged other parts of the case as well. If it was a rare set of cases, you'd go to that trouble, but it's just easier and cheaper with a common engine to find another one.
It's likely going to take more effort than simply sourcing another set of cases and assembling. I believe the recommendation being stated here is to find another engine entirely. If you go with a set of cases and repair the crank (assuming it hasn't been lunched as well), IMO, it's nearly guaranteed clearances for crank mains and connecting rod bearings are things that you'll have to dial in. That in itself requires time and patience and you may find that you're buying all sorts of bottom end bearings in order to get those clearances within spec.
I do have a spare sitting at home already, that’ll go in and then this motor can get the tlc and patience it deserves, although I 100% agree if that wasn’t the case I’d just be shopping for a whole new motor.
Its aluminum, its not like a cast iron block that would make it super difficult to weld. If you were to fix it, just make sure its fully fully clean I would even use a torch and burn off impurities in the inner and outer sides.
As someone who does cylinder plating and repair, RM is correct, not really worth your time. You can’t replate only one cylinder.
I’d have to find someone that would be willing to weld it. It would be tempting if only 1 cylinder could be replated but now that the beeb has corrected me and all 4 have to be done at the same time, it puts it at basically the same price as all new cases from Kawasaki unfortunately.
Sorry I missed the part where you said it hit the cylinder. If the bore is destroyed then I would agree just change out the block. If the damage is slight and at the bottom, then I would rather see you take it to a machine shop to access the damage. Depending on how low the damage location you might be able to get away with welding it then getting that one cylinder bored, and honed. Why do I think its ok, only if its low enough to where the piston rings travel, dont travel past the repaired area. Like I mentioned a machine shop is best for this, as welding a block is a huge pain and if you factor the weld and fab time, maybe cheaper to find a used block.
It is right at the very bottom, but if it has to be refinished it does put it out of a reasonable price range. trouble with all of the used cases is if they’re cheap, they need replating which seems to go for about $1k, putting you at $1500 for replated used cases when brand new ones aren’t much more.
Have you checked on ebay? Im seeing blocks for resonable prices! https://www.ebay.com/itm/4042306778...aP1xw==|tkp:Bk9SR6jft8baYw&LH_ItemCondition=4 https://www.ebay.com/itm/4045013159...8W1EQ==|tkp:Bk9SR6jft8baYw&LH_ItemCondition=4 https://www.ebay.com/itm/4048370239...UGBZg==|tkp:Bk9SR6bft8baYw&LH_ItemCondition=4 https://www.ebay.com/itm/3035001046...tyApCc=|tkp:Bk9SR6bft8baYw&LH_ItemCondition=4 https://www.ebay.com/itm/3047262543...wwOVg==|tkp:Bk9SR6Tft8baYw&LH_ItemCondition=4
