Snapped Head Bolt?

[BoltsMissing]

http://www.google.com.au/search?hl=en&q=metric+bolt+tension+chart&btnG=Search&meta=

Opinions vary....,

Do a test, get a nut and bolt in some piece of wood with a hole and tighten them up till you get a feel of what the tension is. Try wood, plastic and steel tests and purposely break a few by over tensioning using the tension wrench indicator each tme, taking notes of the tension setting.
Once you done this test and see bolt actually break, you'll probably never strip another bolt.


If you are going to use the same head gasket and the engine has never been started, my guess is it should be ok, up the tension slightly, you'll know by then how tight not to go to by doing this simple test.

Tighten in 3 stages, for example if the final tension setting is 25 ft/lbs, then start at 10, 17, 25.

Try without loctite first, my guess at this is, the bolts tension up further due to heat expansion so I don't think they'll loosen up and fall off unless you have not tightened them enough.

 

[KiDD]

OK so either this rod I bought is of low quality, or my torque wrench (new) is poorly calibrated.

I snapped another bolt....

My questions are that since these were torqued down real tight, should I replace these gaskets? I just go to auto part store and buy some gasket material and cut out the shape for the bottom gaskets and for the metal one on the head what do I do? I only ran the engine for a couple of minutes when I first built it but was not running right, then I gapped the spark plug and torqued the head bolts and broke it the first time.

 

[BoltsMissing]

Puts a new twist to your engine, "Snappy Time"

Unless you get some more expirience in not snapping the bolts, a truck load of new gaskets won't make any differance !

Try again using the same gaskets unless the bottom gasket is damaged.
The metal head gasket you may as well change it after to have succesfully torqued bolts without snapping them.
Sorry dude, that's the hard trail ya gonna have to go through, some have the "feel" some need to find it.

 

[kgray]

loctite EVERYTHING. trust me, the vibrations will make it come loose if you dont... If gas hasn't hit the gasket, it should be fine to reuse, too.

 

[KiDD]

the gasket was a little wet

I put the engine back together and it runs again, but I am having trouble getting power at the top end

 

[BoltsMissing]

Good to hear it's running.

If the engine is brand new, then top end may not happen till about after 500 miles or so, on average.
In the mean time order some new gaskets, ride it around and by the time you have done a few miles your new gaskets would have arrived.
Also, tension the head bolts a fraction at a time when it cools down. But don't over tighten. You only need to re-tension once or twice and keep a check on things thereafter.

When the new gaskets arrive and you have done those 500 miles, then do the job again and by that time you ought to things blind folded.
Good work though, you got through a phase and hope you feel those bolts before they snap.

Did you keep a note of the tension settings, if so what were they if you don't mind posting ?

All the Best
BoltsM.

 

[KiDD]

I was afraid to put the torque wrench to it again so I just tightened it till right before I think it would break....

It won't run with the choke open, and bogs when I give it some gas

 

[BoltsMissing]

I was afraid to put the torque wrench to it again so I just tightened it till right before I think it would break....

ok

It won't run with the choke open, and bogs when I give it some gas

check the gap on the plug, 0.025"

check carby and exhasut for tightness.
correct fuel mix ratio.

 

[KiDD]

The instructions that came with the kit said to gap it to .4 to .5 mm so I gapped it to .45ish mm is that too much?

 

[stude13]

it is always best to replace a head gasket that has been tightened.