New Cylinder/ Mis aligned Head gasket

After pulling the head and cylinder off my newly aquired yz450f I came across something that is puzzling to me.

The previous owner told me he installed a new cylinder and piston in the bike.

I noticed the head gasket didnt seem to match the coolant flow ports on the cylinder and head..

When the gasket is installed, it clearly covers up to half of the coolant flow path. This has caused the gasket to boil and start to peel where it it coming in contact with the coolant.

So im wondering if there any chance the guy installed the wrong gasket?

Is there a chance he installed the wrong cylinder?

Is there any way to identify the correct cylinder for this bike??

Here are some photos I took where you can see the bubbling gasket...

Gasket1.jpg

Gasket2.jpg

Looks like a cometic gasket, that may be your problem but in no way am I familiar with your bike.

Try looking at a parts fiche to see what an oem should look like.

That's how the head gasket is supposed to be. The holes are not supposed to match the coolant passages in the cylinder and head. The gasket acts as a restriction so the coolant doesn't flow right through the head without absorbing much heat.

Lots of engines do the same thing with their headgaskets, gmc trucks to 2 and 4 stroke bikes

That's how the head gasket is supposed to be. The holes are not supposed to match the coolant passages in the cylinder and head. The gasket acts as a restriction so the coolant doesn't flow right through the head without absorbing much heat.

See, thats why guy smarter than me design these things..although when I see some designs, I wonder just how much smarter they are..:thumbsup:

Thanks for the info..:p

To add, there are two cylinders for a YZ450; the early and the late. Beginning with the '06, the external oil line for the camshafts was routed internally, and while the head gaskets looks similar, the base gaskets don't. On the '06+, you will find an oil passage at the cylinder base on the crankcase near the right rear head bolt hole, and the cylinder will align with this (it routes the oil around the head bolt).

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