Off topic, engine related :)

[Moody Blu']

I have a 1988 250r honda fourtrax,I bought it in march of this year. It blew up just when I decided to put an engine in the classic.So....(obviously I was dumping money into the boat) it sat until two weeks ago. http://www.donzi.net/photos/my250r.jpg

anyhow...
I tore the engine out and disassembled it. The tranny was in great shape.
The crank was shot(connecting rod lower bearing blew.)

I ordered all new parts for my quad, clutch, connecting rod, crank, seals clutch basket.
heres a pic of the cylinder, I am in the process of completely polishing the whole engine and cases.
the head has been polished and is ready for buffing, the cylinder as you can see needs some work:
http://www.donzi.net/photos/case5.jpg

one problem though.

After close inspection of the case halves, I found a hairline crack in the left case half (to the upper right of the bearing housing)
http://www.donzi.net/photos/case3.jpg
what do you guys think I should do? epoxy? what kind of epoxy if so.
I know a new case half will cost 200+ new. I dont have the funds for that right now. http://www.donzi.net/photos/case4.jpg
I dont see why there would be a problem installing the NEW crank and NEW crank bearings.

It seems to me that when my engine did blow up it blew the bearing(needle bearing) in the lower end of the connecting rod, and somehow worked its way to the crank bearing, Once the piece went into the crank bearing it expanded, and thus made the case crack like it did.

What do you guys think?
Do you guys think that thats why the case is cracked like that?
Do you think it will be ok with new bearings and a true crank?

[harbormaster]

if you prep it well, you could use J&B weld on that case. I had a case on a 125 yamaha that I repaired with J&B weld and it never failed.

[Moody Blu']

Scot, how many hours did you happen to put on that yz125?
was it cracked in a place like mine?

you guys see the hairline crack by the crank bearing right?

[mikev]

being that close to the bearing i dont know if i would take a chance with all those new parts. I have used JB weld alot great stuff but that close to a bearing it will have a whole lot of stress on it and will eventualy break. might be able to take it to a shop and get it welded up but not sure if i would even chance that considering your spending a lot of money on the other parts and if it does crack all the way you will be replacing them all again for probably alot more than $200.00

[Moody Blu']

I guess im gonna be buying a case then :o
wish I didnt have to

[Moody Blu']

get this, the guy at the honda dealer told me that the case is fine and not to worry about it.
I am very skeptical about his analasis(sp?)
Man I am completely in a state of dumbness right now,.
the mechanic tells me exactly the oposite of what I thought he was going to say.
man I am dumb founded...... :o

[Moody Blu']

UpdateI busted my ass on the cylinder for like 4 hours to get it to this point, Im gonna need another 4 hours to get it perfect.
http://www.donzi.net/photos/jug.jpg
what do you guys think?

[Forrest]

. . . better ask the 'Grizz, Sky. He's the Honda factory guy.

[Moody Blu']

big griz and I were chattin on aol, he told me to get a new case.

I really dont have the cash to buy a new case(200+ bucks)so I am going to hope that this forum is right, it may look like deja vu to you guys but, look at the posts: http://pub20.ezboard.com/fhondatrx250rtechhelp.showMessage?topicID=629.topi c they say its a casting flaw.
I hope there right

[MOP]

Just an idea, are you sure its not just casting flash flaws. Looks like a casting mark lines up with it in the picture.

[MOP]

Hi agian I retact the casting idea after looking at the pictues better. The new case is more than likely a good bet.