removing seized spark plug
 

Hi friends

Number 1 spark plug 'may' be seized or may not. I've asked around and I seem to have two schools of thought on what the worst case scenario would be, which would follow from the threads being crossed/pulled. A couple of mechanics have advised that should the threads be pulled that they would helicoil the head and that any aluminium particles that don't get removed will be fine - i.e. won't damage the heads or turbos. Another two mechanics have advised that due to the foreign matter created by the helicoil going into the heads that a top end would need to be done.


What I want to know from the expert is - which is right? Do the heads really need to be opened up just to fix a seized spark plug, or could a helicoil be done safely with most of the particles removed, with remaining particles not being a concern?

Thank you!

a helicoil is the last thing i would use. a timesert is the way to go. Home page. use a considerable amount of white grease on the tap to catch most of the chips. #1 on a 930 isn't the easiest one to fix with the engine in place.

Thanks John. My main concern is the issue of cleaning up what falls into the head - what are your views on that? Would small amounts of aluminum cause issues?

The grease is to keep shavings from going in.

i've done lots of them and no problems. a few tiny aluminum bits are not going to do any damage, as long as there's not a big pile of them. they'll be out the exhaust port real quick. turn the engine over a couple times by hand to be sure nothing is between piston and head before firing it up.

Thanks again that's good to know. Just to clarify its a turbo (930).

Any particles that exit the exhaust port will then hit the turbine impellor and it doesn't take much to tear-up those blades. . .

If the plus is still in the head & you can start the engine, start & warm up the engine. This will swell the head & loosen the plus. every little bit helps

Tom