Engine cover screw

Hey everyone
I need to turn my engine over to TDC to start a head gasket job. The screws that secure the engine cover that I need to get to are seized. I was able to get one out with an impact driver but the other one doesn't want to move. I've tried pb blaster, impact drivers, grabbing it with vice grips, heating it up, and freezing it. I ended up stripping the head with my JIS screwdriver and had to use a dremel to cut a new flat head into it. I know some people with access to a welder would weld on a bolt and unscrew it that way but I have no access to a welder. Does anyone have any ideas as to a next step?

No problemo - get yourself a 6mm heli-coilkit. Carefully drill out the broken screw using the correct drill (usually supplied with the helicoil kit) this will also remove the remaining thread which has seized onto the thread of the broken screw. Just ensure that you apply the drill to the centre of the broken screw - use a centrepunch to mark the centre of the screw and use a small pilot drill first.Follow the instructions provided with the heli-coil and install it - job done!

If you don't want to use the heli-coil thread replacement kit there is a nother option to get your broken screw out. Get yourself a set of "Ezy-outs" they are a tapered, hardened steel drill with either straight or spiral LH cutting grooves designed for the extraction of broken screws

. The method is to drill a hole into the broken screw (as close to centre of the screw as you can) this hole should be big enough to allow the LH Ezy-out to bite into the remaining screw - as you "unscrew" the Ezy-out the LH "thread" bites harder and deeper into the screw until it "jams" then rotates the broken screw remains out of the engine-case thread (that's the theory anyway!)

Be careful to NOT apply too much force to the Ezy-out or it may snap, then you'll have a helluva job to remove the broken Ezy-out as they are VERY hard steel! I tried to remove a snapped-off drain screw from a carb float bowl using an Ezy-out but have not been able to shift it yet and I don't want to snap the Ezy-out! I am waiting for a set of M6x0.75 taps with which I'm going to use to cut the remaining portion of drain screw thread out of the float bowl body.

Hit the screw with a solid lick with a hammer ! This seems to break the oxidation so you can remove the screw. Use Allen head fasteners to replace the Phillips head screws. Z1E sells a kit for the engine.

Kroil. Maybe recut an X into the screw head using a dremel & use a better penetrant.
Give it time to work & use vibration by tap tap tapping a wood block w a mallet or hammer.
LiquidWrench penetrating lubricant did better than the pbb in a test that's floating around the internet.
Kroil is supposed to be the best --- I've had good luck w the LW, but in this case, I'd probably get Kroil.

Pics,need pics.
Steve

Use a drill bit one size larger than the thread size and center drill until the head is gone. This will allow you to remove the cover. You'll now have direct access to the frozen thread area for PB Blaster, Kroll or penetrating oil of your choice. Some of the screw's shaft will also be exposed depending upon the thickness of the cover. It should be enough to grab with a pair of vise grips and back the screw out.

Thanks everyone. I ended up getting easy outs and pulling it out that way. Luckily all the screws inside th cover and on the cover on the opposite side of the engine are stuck too. I'm expecting a fun day :whistle:

Just ride it for another 30 years until they loosen up on their own. Then use anti-seize when you put it back together