head gasket ?

[jbrendel0075]

Need some help w/ a head gasket probelm. Just finished a 440 and blew a head gasket in the first 30 min. of riding. Replaced that gasket wih a cometic gasket that also lasted just one ride. Is their anyone that makes a copper gasket for a 440.

[BigFish]

sounds like u need HD head studs

[blown331]

head studs... or you're running SUPER lean

[dariusld]

What compression and what octane?

[brokenmike]

when tightening the head nuts it helps to tighten them in stages and in a criss cross pattern.in other words don't tighten the first one to 33ftlbs then the next one and so on.tighten them to 10,then20 then 33ftlbs,it helps.i have a 400ex with a 440 kit 11.0-1 piston and a stage 2 hotcam with the original type head gasket with the center enlarged and it has been togeather for 4 years with no trouble

[blown331]

Originally posted by brokenmike
when tightening the head nuts it helps to tighten them in stages and in a criss cross pattern.in other words don't tighten the first one to 33ftlbs then the next one and so on.tighten them to 10,then20 then 33ftlbs,it helps.i have a 400ex with a 440 kit 11.0-1 piston and a stage 2 hotcam with the original type head gasket with the center enlarged and it has been togeather for 4 years with no trouble

This is a MUST. Anytime you bolt down a head you need to follow the torque specs/pattern. If not you're certain to have troubles

Also, your head studs should come with torque lube.. i'd suggest using it or a 5w30 motor oil on the studs to make sure you're getting the correct torque spec

[Ruby Soho]

i blew a head gasket on my 406

the bottom stud was not torqued, that was the reason

[†2005 400ex†]

HD studs, and if their not torqued correctly you will blow head gaskets EVERY ride

[400exrider707]

What compression? If its above 11:1 you probably pulled the head studs out of the cylinder....time for the HD ones.:ermm:

[jbrendel0075]

after the first time we looked at the head studs they looked good (not stripped) used them again just changed the gasket to a cometic. It's 12.5:1 w/ stage 2 cam running 110 gas. Once we take it apart this time going w/ thicker copper gasket .063 and HD studs. Should this solve my problem. thanks for the input.

[jbrendel0075]

aslo has a 450r carb w/ 210k jet

[killed300ex]

hd head studs are a must. I wouldnt build another 400ex motor without them regardless of how minor the engine work is. With 12.5:1 and a 440 you definitly need hd studs. The studs dont strip out its the fact that the material that they screw into inst enough to hold them in. You need a longer and larger diameter stud to hold better. It not as much that they strip out but that when them aluminum expands at diferent rates than the steel stud and you get a little bit of stretching ect that leads to blown headgaskets all it takes is a couple of thousands of stretching and you will blow the gasket. Get the HD studs have a machine shop install them and you should be good to go.
Evan

[02silverpile]

Where is a good place to get the HD studs?

[killed300ex]

www.gtthunder.com should have them maybe c&d would have them be worth asking
Evan