Hailstatedogs 0 Posted September 17, 2020 Greetings! I’m new to the web site and somewhat new to working on four wheelers. My dad and I purchased an 07 Foreman 500 ES with the intent of rebuilding it. We completely disassembled the motor, cleaned it up, replaced some parts, and got it put back together. We had an issue with getting the clutch cover back on and had to use some gentle persuasion with a rubber mallet (lesson learned). Needless to say, when we got it reinstalled in the frame, hooked everything back up, and added the engine oil, I noticed a hairline crack in the clutch cover that oil was slowly leaking from. Before taking it back off the bike, we decided to see it it would crank, and it fired up almost instantly, but the manual shift shaft wouldn’t budge (was also like that when I bought it). We took the clutch cover back off, and the gears changed easily. We determined the crankshaft trying to fit into the clutch cover bearing put everything in a bind, so we now have everything torn down again and will make a more careful attempt at reinstalling the crankshaft. However, when I split the cases again, I noticed something that doesn’t look right. Having never done this before, however, I was hoping someone with some experience could look at the pictures and verify my fear that the crankcase half is cracked. I’d desperately like to be wrong and chalk this up to casting imperfections, so any advice would be appreciated. Thanks! Share this post Link to post Share on other sites
Fishfiles 20,148 Posted September 17, 2020 Hail' , welcome to the forums ------ usually 10 out of 10 times when someone ask about cracks in the case , I would say casing cracks , but this time you have a couple that look like cracks , lets see what others have to say Share this post Link to post Share on other sites
jeepwm69 7,783 Posted September 17, 2020 Eh, I think those are casting flaws, nothing more. You can see some similar flaws in one of the motors I did. Check the end of your crank and see if it's ballooned from someone smacking on it with a hammer. 1 Share this post Link to post Share on other sites
sled_22 845 Posted September 17, 2020 If you don't have a lot of money invested in the case i.e. new bearings, new crank etc. etc., I would just run it. They're probably casing cracks. Stick a thin gasket/seal pick down in the holes and see what you get prying a little if you want. I just rebuilt my transmission on my 06 and had some areas that looked very similar with less pitting. Never blinked an eye at them. 1 Share this post Link to post Share on other sites
_Wilson_™ 6,603 Posted September 17, 2020 3 hours ago, Hailstatedogs said: I noticed a hairline crack in the clutch cover that oil was slowly leaking from. i'd say casting flaws ... nothing more .. but you did mention an oil leek Share this post Link to post Share on other sites
87Iroc 344 Posted September 17, 2020 (edited) I say casting flaws as well. These are made from Die Castings. The alumimum forms that type of feature when it cools in the mold. I had that fear on mine in a few places but looked and they looked like flaws. Do you see the same mark in the same spot on the back to say they are a thru crack(I don't think they are cracks). I just looked at my 450 rebuild thread this summer. I have flaws but not as many as you. I'd say it was cooling too quick in their mold but I'm not an expert. I'd put it back together and be careful of the clutch cover. It should go together lovingly but not need a hammer. Edited September 17, 2020 by 87Iroc Share this post Link to post Share on other sites
shadetree 6,036 Posted September 17, 2020 casting flaws, but dont smack it with a hammer !. 1 Share this post Link to post Share on other sites
87Iroc 344 Posted September 17, 2020 44 minutes ago, shadetree said: casting flaws, but dont smack it with a hammer !. listen to the guy. And don’t buy Chinese parts. It’s an unforgivable sin 1 Share this post Link to post Share on other sites
Melatv 797 Posted September 18, 2020 Hi: Big Welcome Here Share this post Link to post Share on other sites