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Bike eats gaskets like they’re nothing

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On my xr250 I seem to have this issue where it keeps blowing head gaskets. The first time it was due to the wrong size. After replacing it the high pitched squeak/cracking sound followed by smoke from the left side of the head gasket (white smoke) is coming out. The bike is definitely in need of a tune up, but that couldn’t be what’s causing the blowing headgaskets, could it be? Current head gasket is OEM. Both surfaces from the head and cylinder have no warpage, scratches, dings, etc. It’s always the same side as well.

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Are you following torque procedure? ie: small increments, sequence/pattern. have the head blots/studs been replace with ones that are to long and bottom out?

post some pics of both surfaces.    

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using a good torque wrench is critical! I didnt think i needed one all the time,as i have been wrenching for 50 years,so i did a test about 15 years ago. I torqued a head by feel,felt perfect. Then put a torque wrench on the bolts,and was shocked at the difference i found between a few of them,i KNEW they were close by feel,I was so W R O N G ! Get a good torque wrench,and dont leave the tension on it when you are finished,put it back to zero

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using a good torque wrench is critical! I didnt think i needed one all the time,as i have been wrenching for 50 years,so i did a test about 15 years ago. I torqued a head by feel,felt perfect. Then put a torque wrench on the bolts,and was shocked at the difference i found between a few of them,i KNEW they were close by feel,I was so W R O N G ! Get a good torque wrench,and dont leave the tension on it when you are finished,put it back to zero

I would’ve never suspected that. I’ll be sure to pick one up

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Are you following torque procedure? ie: small increments, sequence/pattern. have the head blots/studs been replace with ones that are to long and bottom out?
post some pics of both surfaces.    

I have not been following torque procedure no. Each of the 4 bolts is a different size. While sitting out they may have been moved around. I’ll check a parts catalog and pickup a torque wrench.

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Proper torque and Cometic layered steel gaskets and you will never need to touch it again.  The stock fiber and copper are junk.

Edited by BOAB

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Proper torque and Cometic layered steel gaskets and you will never need to touch it again.  The stock fiber and copper are junk.

Gonna borrow a torque wrench from a friend. New gasket on its way

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5 minutes ago, spezza-125 said:


Gonna borrow a torque wrench from a friend. New gasket on its way

head.png.34157128e7830d5d70b55127dbe2c826.png

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On 10/4/2019 at 2:09 PM, spezza-125 said:


Gonna borrow a torque wrench from a friend. New gasket on its way

Just trying to be clear. You have not been using a torque wrench on the head of your bike and you are shocked the head gasket has been failing?  How do you know your head surface isn't warped? 

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8 hours ago, MaxPower said:

Just trying to be clear. You have not been using a torque wrench on the head of your bike and you are shocked the head gasket has been failing?  How do you know your head surface isn't warped? 

Had it checked when the head went in to be re threaded, cylinder too.

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Are you following torque procedure? ie: small increments, sequence/pattern. have the head blots/studs been replace with ones that are to long and bottom out?

post some pics of both surfaces.    

IMG_7114.thumb.JPG.ee69bce2e364794c985826f8db68bbe5.JPGIMG_7112.thumb.JPG.4c2065b9530d573a35ecf3dc02ee1824.JPGIMG_7113.thumb.JPG.94ecddba80694b9e14efc4d5ec1f02ec.JPG

Here are some pictures. You can see the black scoring where the crackling and smoke from huge gas jolts would occur.

 

The head itself looked perfect. No scoring or black marks or anything. Shiny and looked fine

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 isn't there supposed to be a dowel on the intake side of the head just like the one on the exhaust side, maybe the cylinder isn't torqued correctly as well.

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 isn't there supposed to be a dowel on the intake side of the head just like the one on the exhaust side, maybe the cylinder isn't torqued correctly as well.

I think it’s stuck in the head... I’ll check

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