Any advice to help me undo the "cream cheese" 4mm allen bolts that hold on the cover next to the camshaft end. I have tried a good fitting 4mm allen key; a 4mm allen key with an impact screwdriver - all to no avail! The bolts are now distorted and I'm at a loss. I don't have access to a lot of specialist tools and with the heads being "flush" with the cover surface I can't put a slot in them safely without damaging the cover itself. Thanks in advance.
And if you haven't got any Torx bits, sometimes just using a small punch to fit inside the Hex of the bolt head, and giving it a good thump with a hammer can "shock" the threads lose, and it may then come undone.
Combine the two and it will be the best chance you have. The torx bit tip works most of the time but if the bolt is in really tight then you may find it difficult to impossible to move. If that happens you could try one of these to see if that will shift it as they tend to dig in more as you apply pressure, drilling a slightly deeper hole will help with getting more purchase on the bolt. BOA Grabit Screw & Bolt Remover Drill Out 2 Piece Set | eBay
It can be a 50/50 option with those 'bits'..............they normally work pretty well and sometimes with socket cap screws (allen head) there is no drilling necessary........ ....unfortunately two things can go wrong..........1) Drilling can weaken the bolt head where it meets the reduced diameter of the bolt shank or thread and it the head is ripped off..........Not an insurmountable problem if all the other bolts can be got out or sheared off. And 2) The worst result is the threaded tip of the bit shears off and it is left stuck in the bolt.......you won't drill that out easily.
BTW........I wouldn't try using a left hand thread extractor in any of the small size bolts / screws (M6 and down).........bound to snap, virtually impossible to drill out.
From my own experience I have broken off the head of an m6 hex bolt and then trying to use an easy out broke that too! An absolute nightmare to drill round it to get it all out. My advice, try any of the methods above but watch out for hardened easy outs/screw extractors that look flimsy or are cheap as its not worth it. If you do end up making a mess these engines are easy enough to helicoil after, mine have a few from previous hamfistedness and one or two of my own efforts.:fearscream:
In my experience the easiest and most effective way to get these out is to drill the head off, remove the cover and then unwind the the remaining stud with mole grips or in many cases, by hand. It's often the case that the threads are perfectly free running and it's the head of the fastener that's stuck to the casing.
Thanks for all your help and advice guys. The oversized torx worked on one bolt and I had to drill out the head of the other. Anyway, its all done now just got to find some decent replacement bolts. p.s. Disappointed nobody spotted my "deliberate mistake" when I mentioned camshaft instead of crankshaft. You were probably just shaking your heads and nodding wisely and thinking to yourselves "I'll say nothing!!". So in no particular order thanks; jimmer, Desmoquattro,Arquebus,Red998,Cream_Revenge and NZDave.
While I have the rather scruffy cover off, is there another , more attractive alternative that I could buy at a not too ridiculous price? Source etc. Cheers.
We all allow for simple errors...............(except spelling and grammar)..............Polish it..............
