Huge Vacuum Leak?

[87-325ic]

so i just did a valve adjustment, which the valves sound much better. i did a hot, tight .012 and the .010 slips in and out just right. .013 doesnt go in at all. so the valves are good.

my problem is a Real bad rough idle, jumpy, lumpy, and studdery. while driving, it rides pretty smooth, but letting it go back to idle, it just about dies sometimes. a little bit of a rough/ uneven lower rev range. but normal driving seems "okay"

The reason i think its the vacuum leak is b/c i put the valve cover back on without a gasket. Now, before you freak out on me.. listen..
A long time ago i broke one of the studs sticking out of the head.. and they are loctited into the head. so i cannot easily replace the stud. therefore i cant put a nut onto the stud.
So because of this i have been using a little gasket maker on top of the oem gasket.

This time i just planned to use only gasket maker, which says its for valve covers, since i didnt have another new gasket, and the old one was all gummed up with gasket maker. Previously i had no major vacuum leak, but some loud valves. now i have quiet valves and a huge vacuum leak.

Is the gasket maker stuff any good? it seemed to definitely help when i had it on the gasket too, but alone it doesnt seem to work.



Any suggestions?

[xwill112x]

just buy a sheet of generic gasket material for cheap and cut as needed.

[jlevie]

Getting a broken stud out of the head if there is any of it that can be grabbed with vice grips is no big deal. Heat applied to the casting will soften the thread locker. Use a propane torch to heat up the thread area while applying torque to the stud. When that area of the casting gets above about 300F the thread locker will let go.

[87-325ic]

I had tried to do that a while back but got really worried that i might damage the head with that torch, or worse, catch my whole front end on fire. theres eough sticking out to grab, but not enough to stick past the valve cover.

i would really like to remove all the studs, and re-tap them. some of them seem to not hold as tight. its a bit of a mess...

What do you suggest as far as getting a good seal again? try again with just gasket maker? or go get a new gasket and use the gasket maker too, like i did last time and seemed to get decent results?

i know im pretty much answering my own questions here, but other peoples suggestions really do help.

[xwill112x]

if you clean the surfaces well on the head and valve cover, a gasket should be enough.

[87-325ic]

even with a missing bolt on one of the corners..?

[SpecM]

even with a missing bolt on one of the corners..?

no, do what Jim said and pull out the stud, and replace it, even with a bolt

you wouldn't hurt the head (its designed to withstand head, ya know?) and be carefull and you wouldn't catch anything on fire.

[xwill112x]

even with a missing bolt on one of the corners..?

the oil pan on my m42 is missing 3 bolts. it doesn't leak a drop.

[SpecM]

the oil pan on my m42 is missing 3 bolts. it doesn't leak a drop.

maybe, but air is thinner than oil

[87-325ic]

so i want to heat the inside of the head, at the spot the stud goes in, (its the front left corner bolt)

ill try it again. with the car as hot as i can get it too. if i dont succeed.. ill try to throw a gasket in.
Is the gasket maker on its own really that bad?

Also, ill double check the valves. but i feel pretty good about them.all have space b/w the rocker eccentric and valve stem, so i know all the valves close fully. anything wrong with the clearance and ill just be getting a little too much lift huh?

[jlevie]

Wipe all the oil within 3" of where the stud is away. I usually use an oxy-acetylene torch and 0 tip for this as that is a small concentrated heat source. At the expense of smoking some oil, a propane torch will work.

[87-325ic]

what ind of time does it take to heat it with a propane torch? ive tried this before and started worrying about really messing something up

[87-325ic]

with the car idling, i removed the valve cover cap, not too much change. this tells me i have a nice vacuum leak somewhere close..

so i pulled the valve cover back off and looked at the gasket sealer..
im not a fan anymore.
near the bolts, it seemed to have squeezed out to a nearly nonexistent layer, and near the corner without the bolt, it seemed to barely squeeze at all.
not only this, but a bunch squeezed inside the engine too, making it vulnerable to falling in and clogging something up...

I will soon be getting a new gasket (on monday) and will try very hard again to get that damn broken stud out.

Any tips on getting a good seal when putting it back together?
and, what do i need to do to the threads If i get the stud out the head? tap or anything?

[SpecM]

Any tips on getting a good seal when putting it back together?

just clean all that goo off, and lubricate the gasket with a little clean oil

[87-325ic]

that stuff actually came off in mostly full pieces, except where it was real thin; which my fingernail took it right off.

i thought i wanted a clean dry surface... not one with an oil residue.. can you explain this for me please?

wanna drive down to fayetteville and help me get this stupid stud out? you know you want to!