rebuild now leaks?

[JDiesel]

Hey Everyone,

I rebuilt my 1.6 and everything went great.  I tightened the TTY head bolts 1/4 turn after 1000 miles. Now its probably 5000 miles later and there is a slight oil seepage on the back of the motor by the headgasket. Should I do another 1/4 turn on the head bolts?

Thanks
JD

[burn_your_money]

It's probably your valve cover gasket.

[JDiesel]

Nah, its not the valve cover gasket. Its clearly coming out between the head and the block right at the head gasket. Only on the left side of the motor by bolts 10 and 4.

[JDiesel]

Come on guys... can anything get hurt from tightening stretch bolts 5000 miles later? Can they break? Can I mess up my head-gasket?

[Gizmoman]

Not sure, but if it were mine I'd give it a go with a good (and trusted) torque wrench.
Cant hurt the gasket. and running it with a leak could actually do more harm than good IMHO.

TTY bolts are just that though and if you went over - it's over

[fatmobile]

Right, if you do want to check the torque,
 use a torque wrench, one of the needle types.
 Back it off a little and torque it until the torque doesn't rise anymore, that means the bolt is stretching.
 It should happen around 95 lb ft. probably a little higher.

 If one's bad they might all be bad.

[JDiesel]

So just giving each bolt 1/4 turn is a bad idea?  I know i got each one to 80 ft lbs and then did 1/4 turn on each one after 1000 miles.

[Gizmoman]

1/4 turn with no torque wrench is a bad idea.
If you exceed the bolt's design limit (you may have already), the bolt must be replaced.

TTY bolts are very stiff springs. Ever stretched a spring and then tried to push it back to it's original length? Over-stretching changes the molecules forever.

Not saying yours are over-torqued or damaged, but it sounds like you may not not have a torque wrench and want to just turn them another 90 degrees. If you do have one, fatmobile's advice is solid.

[JDiesel]

It's probably your valve cover gasket.

Welllll..... you were right.  :-D.  Thankfully!

So I replaced the cork valve cover gasket. Same leak, cam-sproket side rear corner.

Am I potentially over tightening?
Do I need contact sealant where the rubber half-ring plug meets the cork gasket?
Should I switch to the rubber gasket kit?
How do I test the valve cover for warps? Maybe its time for a new one...

Thanks guys
JD

[Gizmoman]

IMHO, rubber is typically better than cork.
I'd check the flatness of the cover - sounds like it's warped in that corner.

If you really want to seal it, spray on a bit of hylomar (all mating faces)

[ORCoaster]

I always dab a small bit of sealer between the half moon and block piece of a cork gasket set.  I would check all the bolt holes with a flat straight edge of some sort.  Clean and look it over real good.  You may have that corner with some sharp edges that cut into the gasket and cause it to leak. 

[burn_your_money]

Upgrade to a G60 valve cover, they don't warp. Any straight edge that will fit inside the valve cover should be able to tell you if it's warped or not.

[fatmobile]

Yep, rubber gasket,
 one with the metal insert that keeps it stiff. Not the floppy spineless ones NAPA sells.

  Don't use the stock studs provided with some gaskets, the bald spot in the threads won't let some folks tighten the nuts enough.
 Get a set of long set screws.

[Toby]

So just giving each bolt 1/4 turn is a bad idea?  I know i got each one to 80 ft lbs and then did 1/4 turn on each one after 1000 miles.

Yes a very bad idea. Do it just like the head gasket directions say. They are not all the same and you can not improve on it. Or did it say tighten to 30 then 43 then a 1/4 turn. Or did it say 20 then 1/4 turn, then 1/4 turn warm it up and do another 1/4 turn then at 1000km do another 1/4 turn. You need to read the directions for that particular gasket. FWIW it is possible to pull the threads out of one of these blocks by overtightening stretch bolts.

As far as the VC gasket goes, do you have the big hole gasket and the studs with the "hat" in the center? Those almost never leak and you just tighten them until the nut pinches the tin cover to the hat on the stud. A dab of RTV in the corners of the cork gasket/rubber U interface never hurt anything. You need to let the RTV set before you run it though or the RTV turns to goo.