YZ250 Crankcase fix

Headshake
Profile picture for user Headshake
Posts
50
Joined
2/15/2013
Location
Hartford, CT, USA
Headshake
Edited Date/Time 12/9/2013 7:29pm
I have been working to get my 2009 YZ250 ready for sale when I discovered a hole in the case right in front of the countershaft sprocket. The hole looks like it was repaired with JB Weld or something similar. It was hidden behind the countershaft sprocket cover/guard and I didn't know about it until now. I'm the third owner of this bike and was planning on selling it. I don't really want to sell it with a half-assed repair or be dishonest about it with a potential buyer. Is this a legit repair or something that needs to be handled differently? I really don't want to replace the case as I would be giving the bike away at that point. If it leaks any oil from the hole I haven't seen it in about 5 hours of riding.



|
crashnburn11 12/8/2013 3:09pm
12/8/2013 3:09pm
If it doesnt leak, that isnt a load bearing portion of the case so it would hold up fine. If it isnt good enough someone like eric gorr (or a local tig welder) will weld them up with some filler rod. I think eric gorr charges $50-150 depending on the extent of damage
harescrambled 12/8/2013 3:12pm
12/8/2013 3:12pm
I'm not familiar with that particular engine, I can tell you that if the clutch actuator rides in that galley where the JB weld is (Which it looks like it does to me), it's a sketchy repair, and also....JB weld is never a legit repair for cases. It's gonna leak or break out at some point, and you'll have an irate purchaser to deal with afterwards. Better to buy used cases off ebay and eat the cost. You'll have peace of mind if you do.
harescrambled 12/8/2013 3:14pm
12/8/2013 3:14pm
crashnburn11 wrote:
If it doesnt leak, that isnt a load bearing portion of the case so it would hold up fine. If it isnt good enough someone like...
If it doesnt leak, that isnt a load bearing portion of the case so it would hold up fine. If it isnt good enough someone like eric gorr (or a local tig welder) will weld them up with some filler rod. I think eric gorr charges $50-150 depending on the extent of damage
that looks like the clutch actuator rides there...if it does, you're talking about tig welding and remachining...
crashnburn11 12/8/2013 3:24pm
12/8/2013 3:24pm
Maybe, you might be able to use a piece of steel rod as backing when welding that. Worst case it needs a drill plunged in from the tranny side.

The Shop

See All »
Headshake
Profile picture for user Headshake
Posts
50
Joined
2/15/2013
Location
Hartford, CT, USA
Headshake 12/8/2013 3:35pm
12/8/2013 3:35pm


Thanks for the information. Maybe this picture better shows where the damage is.
xnationalwrench 12/8/2013 3:40pm
12/8/2013 3:40pm
I guess it sort of depends on what your going to sell the bike for? Top dollar I would replace that main case (Yamaha does sell the main cases separate retail about $600.00) I can't really see if the clutch actuator so not sure what is on the back side but it appears that a chain was thrown and caused the damage so welding could be an option, to me JB Weld is not an option as a fix (maybe at the race track as a quick fix)
Headshake
Profile picture for user Headshake
Posts
50
Joined
2/15/2013
Location
Hartford, CT, USA
Headshake 12/8/2013 3:56pm
12/8/2013 3:56pm
I'm definitely not looking to get top dollar for it. It's a high hour bike that I bought as a project but I just don't have time for it. I just want to repair it so I can be up front with a potential buyer about the condition and know the bike is safe and not a time bomb. I don't want to screw somebody over.
sleeve1
Profile picture for user sleeve1
Posts
698
Joined
11/24/2013
Location
Meadville, PA, USA
Fantasy
467th
sleeve1 12/8/2013 3:58pm
12/8/2013 3:58pm Edited Date/Time 12/8/2013 4:01pm
i'm a welder by trade. i've done this repair before. you need a round piece of 4140 pre hard steel turrned to the size of the actuator bore then you can TiG weld the damage from the outside. (the steel acts as a heat sink reducing warping and does not let weld matter into the bore) a good weldor should be able to do this without warping the case. after welding some grinding and polishing will make it look like it was never repaired. good luck. hope this helped. splitting the cases is the best way to do this repair.
Headshake
Profile picture for user Headshake
Posts
50
Joined
2/15/2013
Location
Hartford, CT, USA
Headshake 12/8/2013 4:34pm
12/8/2013 4:34pm
Thanks everyone for the responses. It is much appreciated.
TerryK
Profile picture for user TerryK
Posts
9899
Joined
8/17/2006
Location
CA
TerryK 12/8/2013 7:09pm
12/8/2013 7:09pm
sleeve1 wrote:
i'm a welder by trade. i've done this repair before. you need a round piece of 4140 pre hard steel turrned to the size of the...
i'm a welder by trade. i've done this repair before. you need a round piece of 4140 pre hard steel turrned to the size of the actuator bore then you can TiG weld the damage from the outside. (the steel acts as a heat sink reducing warping and does not let weld matter into the bore) a good weldor should be able to do this without warping the case. after welding some grinding and polishing will make it look like it was never repaired. good luck. hope this helped. splitting the cases is the best way to do this repair.
This, or find a good replacement on ebay. Guys part out perfectly good bikes all the time.
Kawirider
Profile picture for user Kawirider
Posts
467
Joined
10/28/2008
Location
USA
Kawirider 12/9/2013 12:44pm
12/9/2013 12:44pm
My 09 YZ did the same thing I had to split the cases to have it welded then I blew the case apart putting new main bearings in it so I ended up having to get a new left case. Make sure you take all the bearings out when you have it done.
crashnburn11 12/9/2013 6:19pm
12/9/2013 6:19pm
Kawirider wrote:
My 09 YZ did the same thing I had to split the cases to have it welded then I blew the case apart putting new main...
My 09 YZ did the same thing I had to split the cases to have it welded then I blew the case apart putting new main bearings in it so I ended up having to get a new left case. Make sure you take all the bearings out when you have it done.
Use the old freeze the bearings, heat the case trick. Bearings will just fall right in and seat all the way
Headshake
Profile picture for user Headshake
Posts
50
Joined
2/15/2013
Location
Hartford, CT, USA
Headshake 12/9/2013 6:43pm
12/9/2013 6:43pm
I'm bringing it to a welder this week to have it looked at and I'll take it from there. I then have to figure out if I want to tackle splitting the cases myself or not. If I end up getting it repaired I'll throw some pics up here to see what you guys think. Thanks again for the input.
str8shooter
Profile picture for user str8shooter
Posts
687
Joined
1/6/2013
Location
USA
str8shooter 12/9/2013 7:29pm
12/9/2013 7:29pm
I feel like Im in the same boat where I cannot sell my 06yzf! I blew a chain and it wadded up in the cases and took a good hunk out of the cases right at the clutch actuator post. I DID fix it with JB weld and it hasn't given me one problem or leaked........YET! I could always try to find new cases but the bike isn't worth the cost it would take to make it right. at this point Im thinking of parting the bike out but it still runs rides and rolls great! That bike has been one of the most reliable Ive ever known!! It owes me nothing!

Yours really isn't anywhere near as bad as mine was but you could always inform potential buyers of the repair and see what happens. just drop the price a little to motivate a buyer

Post a reply to: YZ250 Crankcase fix