Morning all, So the last time I changed my belts, I added a drop of red threadlocker to the crankcase centre cap screws as per instructions in the Haynes. Come today, and I thought I'd begin the 6K service by checking the torque on the alternator nut, and ticking off new coolant, oil & filter while I was at it. No dice whatsoever getting the centre cap screws to move. Google tells me the only way to remove is by heating said screws to 200°C and disassembling while hot! The prospect of scorching my crankcase does not appeal. What are my options? Is an easy out drill bit worth a shot?
I would use the hammer and chisel method on those screws rather than a drill, which will quite likely damage the threads in the case. I have never used loctite on those threads, especially not the red stuff. I've also never seen them get loose. Also, replacement screws are usually countersunk so they don't catch the fairing etc. When you get new screws you can sand and refinish that cover I reckon
Try hammer type impact driver, these are a couple of quid from screwfix or toolstation. Put the screwdriver head in the slot, gently twist in the direction to undo and hit with a hammer. This drives the bit into the screw and shocks the thread in the right direction.
Don't drill it out, the loctite bonds the thread of the bolt to the tread of the case. You have no chance of drilling it out straight. Heat is best. It probably doesn't need 200 degrees. Impact driver is also a good try to just break the bond. Thread lock is great stuff but using the right amount of the right type is paramount. You are filling the space between the male and female thread. That is not a lot of space so a "drop" is a huge amount.
Looking at the screw heads they are too chewed up to grip on. I would carefully centre dot the head and drill with a small drill bit no more than 2mm dia to a depth of 3 to 4mm then enlarge with a 5mm drill to the same depth and finally a 6mm drill until the head of the screw comes off. When both are done you can remove the cover and remove the stubs with grips or similar. The critical part is getting the first hole drilled centrally so take your time setting up carefully for this and use new sharp drill bits.
As said above, some heat should get those moving. Also, where you've said "Red" threadlock - I'm assuming that means High Strength Loctite, 270, 271 or similar? There's really no need for such a strong threadlock on those bolts, the low strength would be fine on such a "non-structural" fastener - it's just there to prevent them vibrating out. 222 or at a push 243 would be plenty strong enough.
I've never used lock tight on them bolts before, if you're worried about them vibrating loose a touch of silicone sealant under the head before fitting would be sufficient to do the job.
Thanks a bunch everyone. I have clearly goofed up, but learnt something on the way. The exact product I used was Permatex Threadlocker Red (in case anyone was wondering). Impact driver after heating up with a soldering iron sounds like a plan. Although the progressive drilling method espoused by hugh makes sense and will be my back up. Sev- I did indeed try tightening first with a very wide bit screwdriver. No dice, and now have the burred head issue. Will replace with hex screws once I get these guys out. Definitely need a punch to get a deeper slot for the driver. For what it's worth, here is the Haynes section I followed (28) that advises using locking compound:
Agree with only needing a drop of 222 for those screws and only on the thread - none under the head! Loctite 222 is pink by the way
I have used the wifes hairdryer with great success on breaking the red loctite grip, much to her delight
On my 916 I replaced the countersunk screws with cap head. I made some countersink washers by cutting the head off some countersink screws and drilling them through the centre. Then I had some proper cap head Allen recess screw heads that don’t chew up like the teeny Allen recess countersunk ones.
I have undone slotted screws with a center punch and hammer. You need a punch with a sharp point, a light strike to seat it in the slot then belt it anticlockwise until it starts to turn.
Get the bike up to temp then try the impact driver, if the head chews up then your going to have to use the centre punch method, I've had a lot of success using a ground piece of high speed Steel ground to give maximum contact with the screw head. Good luck with it
