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Discussion Starter #1
i had a break in my engine case where the stator will go,i got it welded in the weld is flawless,it didnt leak as bad with liquid gasket,but when i put on a paper gasket oil just pours out,i don't get wtf is going on,is it possible to buy the lower half of the engine case? or would i have to buy it as a whole
 

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I've always read that you can't mix and match case halves, but have never actually tried it (it's not worth the risk of it going bad after all that work and money). I don't use paper gasket anywhere on my 900RR. The head gasket and valvecover gasket are the only gaskets on my engine and it's totally leak free (I'm actually kinda anal about leaks). Try some Hondabond, I bet it will seal. That stuff is best sealer I've ever used.
 

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:plus1: Ditto. The engine cases are mated to each other. You could "try" but I wouldn't. And Hondabond is some amazing stuff.
 

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Discussion Starter #4
well when i bought my bike i noticed my cases are mismatched,the top looks brand spanking new and the bottom looks all old and ****
 

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well when i bought my bike i noticed my cases are mismatched,the top looks brand spanking new and the bottom looks all old and ****
I doubt that indicates they're mismatched.
 

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i had a break in my engine case where the stator will go,i got it welded in the weld is flawless,it didnt leak as bad with liquid gasket,but when i put on a paper gasket oil just pours out,i don't get wtf is going on,is it possible to buy the lower half of the engine case? or would i have to buy it as a whole
The reason you can't mix lower and upper cases is because the main bearings for the crank are held by the upper and lower cases. The main journals in the cases are machined with the two halves of the block bolted together and torqued to spec. Once this is done the upper and lower cases are a matched pair and can't be mixed with other upper or lower cases. This insures that the mains are perfectly round. So when the bearings and crank are installed and the two engine cases are torqued together the crank can spin freely without damaging the crank or bearings. If you mismatch lower and upper cases the main journels will no longer be within the specs required for the crank to spin freely and you will damage the bearings and the main journals on the crank.

Now if you find a good machine shop there is some ways that they could make a new lower and your upper case work but it will probably cost more than buying a complete case off of ebay.
 

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Discussion Starter #8
ah,thanks alot for the insight :)

as far as the oil leak,i'm completely lost,oil isn't even leaking out of the weld,and it was also straight edged,it just drips out the bottom of the engine case where the stator cover meets,but,it has gasket and bolts completely fine
 

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as far as the oil leak,i'm completely lost,oil isn't even leaking out of the weld,and it was also straight edged,it just drips out the bottom of the engine case where the stator cover meets,but,it has gasket and bolts completely fine
You really should try once again to identify where the oil leak is coming from. By your first post it sounds like in the gasket sealing area. My suggestion is get a new Honda gskt, check both surfaces carefully with a fine flat file for flatness and reassemble with a small amout of good RTV sealer on both sides of the gasket and tighten evenly.

Allow to set overnight and when you start it, be ready with a good light and mirror if needed to watch where the leak starts from, if still there. Wipe clean and check again. I'm guessing the suface isn't flat or a small hairline crack is still there. Either way you should be able to repair with sealer once you know exactly where it's coming from.
 

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Discussion Starter #10
well,i just put a brand new honda paper gasket on there,and i havent even started the bike,the other day i just used RVT and it didn't drip out as bad as it did with gasket then gasket + rvt

when i take the stator cover off the bottom of the gasket is wet from oil

everything is very even and flat,i'm just going bonkers i'm about to weld the stator cover to the damn bike already lol
 

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I know how you feel but be patient. You must be missing something. Everything you say sounds good but did you look under with a good light as I said to spot where the leak starts? One of the surfaces must be bad or a crack even along side the weld edge. Also all the surfaces must be spotless of any oil before using sealer. I use brake cleaner because it dries fast and doesn't leave a residue.

You are our eyes right now so make it happen FTP.
 

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The reason you can't mix lower and upper cases is because the main bearings for the crank are held by the upper and lower cases. The main journals in the cases are machined with the two halves of the block bolted together and torqued to spec. Once this is done the upper and lower cases are a matched pair and can't be mixed with other upper or lower cases. This insures that the mains are perfectly round. So when the bearings and crank are installed and the two engine cases are torqued together the crank can spin freely without damaging the crank or bearings. If you mismatch lower and upper cases the main journels will no longer be within the specs required for the crank to spin freely and you will damage the bearings and the main journals on the crank.

Now if you find a good machine shop there is some ways that they could make a new lower and your upper case work but it will probably cost more than buying a complete case off of ebay.
so does that mean if you go swaping the lower half the best is to rebuild and get machine every thing that goes inbetween the upper and lower half?
 

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so does that mean if you go swapping the lower half the best is to rebuild and machine every thing that goes in between the upper and lower half?
No, but you must properly inspect and measure the oil clearances and gasket surfaces.
 

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When the cases are machined, there aren't all the exact same size. That's why you have to cross reference code on block to code on crank web. You might have an "A" size upper case and a "B" size lower. I'd just do what he suggested and buy complete cases on ebay. You can find them pretty cheap if you're patient. I have 3 spares for my 9RR. One set I got for 50 bucks.
 

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Try the Hondabond with or without gasket. All you have to lose is about 8 bucks.
 

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I lowsided my old 929, and thought that the only thing broke was the stator cover when i replaced it and filled with oil it poured out like a gutted pig, what happened was that the lower cracked all the way down to the swing arm pivot and there was a hole about the size of a nickle, I bought a lower case from JF Motorcycle frames(used) for $550 bucks, did a complete engine rebuild since the engine was all taken apart anyways, and the bike worke great afterwards.
 

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I lowsided my old 929, and thought that the only thing broke was the stator cover when i replaced it and filled with oil it poured out like a gutted pig, what happened was that the lower cracked all the way down to the swing arm pivot and there was a hole about the size of a nickle, I bought a lower case from JF Motorcycle frames(used) for $550 bucks, did a complete engine rebuild since the engine was all taken apart anyways, and the bike worke great afterwards.
I've known two 929 owners that broke their cases through the swingarm pivot in crashes.
A lower case for $550? That's a hell of a price. You could buy a complete running engine for about twice that?
 

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I've known two 929 owners that broke their cases through the swingarm pivot in crashes.
A lower case for $550? That's a hell of a price. You could buy a complete running for about twice that?
Nowadays things seem to be cheaper, but back in 03 I didint think much of the price, I was glad i found one used at the time.
 

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Nowadays things seem to be cheaper, but back in 03 I didint think much of the price, I was glad i found one used at the time.
Have you still got the bike? How much mileage has it done since the rebuild?
 

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naw, I sold it to a friend shortly, he rode it as a comuter untill he wrecked it in june of 06, so he tacked quite a bit on.
The bike ran strong untill then, he still has it, and swers he will bring it back to life some day.
 
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