Blowing the head gasket

[buzzy613]

on my 85 atc 250r i cant go ten hours on a head gasket without it blowing, then it blows out. i think there might be hairline cracks in the head, i bought a new head for $30 bucks and it has to be milled.After get it milled im goings to have the machien shop cut and an O-ring in the head. Is there any thing els that could be causing the head gasket to blow?

[hoosierlogger]

cheap head gaskets?

[code200k]

Not trying to insult you but how are you putting them on?

[shortline10]

Read this thread it will help you fix the issue :beer

http://www.3wheelerworld.com/showthread.php?129696-86-250R-head-gasket-woes&highlight=

[dcreel]

It's probably the cylinder head..

Use oem head gaskets
Check for straightness of the mating surfaces
Use copper spray on the oem gasket
Use a quality torque wrench
Torque head before you mount the head stay
Torque the head to final torque in 3 steps using a criss cross pattern

[Xpress]

Lots of variables. You absolutely have to make sure you have a straight head, and that you are using good quality gaskets as well as torquing the bolts down to the proper tension.

[ron1576]

Do you re-torque the head at all?

[Xpress]

^That is also something else to consider.

On my dads truck, we ran it easy for the first 100 miles, then progressively ran it harder. Then we also re-torque the head bolts after 50 miles, 100 miles, 250 miles and 500 miles. You'd be surprised how much head bolts loosen if you don't tend to them within the first 500 miles or so.