1999 Big Bear 350 Cylinder Head Crack

[Beast3]

So I have oil that comes out of out a small crack next to one of the top bolts.

Anyone know a way to seal this or fix it without buying a whole new cylinder head?

I was hoping there was something I could put on the crack to seal it or I know a welder that could just weld over it??

Thanks again,

Keith

[oxidized_black]

you could try some high heat manifold silicone ... its a 50/50 chance ...

[marioweldinginc]

Try JB Weld or something along those lines. Or like you said bring it to a machine shop

Sent from my SGH-T989 using Xparent BlueTapatalk 2

[Beast3]

I went and bought some high temp silicone but when looking closely at the 3 bolts on the cylinder head

they all seem to have some sort of slit next to the bolt so I'm guessing this is normal and not a crack since they all have what looks to be this.I do have oil coming out from the top bolt which is #11 on most oem specs for my big bear.

What are some of the issues that could cause oil to come out of this bolt? I noticed it did have a metal washer and that is all the oem graph shows goes with the bolt.Below is link to blow out of my big bear and Im referring to the cylinder head section.

1999 Yamaha Big Bear 350 2WD YFM350UL Parts, 1999 Yamaha Big Bear 350 2WD YFM350UL OEM Parts - BikeBandit.com

Thanks,

[oxidized_black]

i think the causes might be too much oil and/or a vent line not breathing. that would build up pressure

[Beast3]

OK. Thanks again for the info.