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Crankcase - block gaskets

I have to replace a sheared crankcase/block stud on my blown car so the block is coming off. I've always been a believer in Loctite 515 in place of the gasket. However the new silicon/fibre gaskets weren't around last time I did this.
They appear to be very effective but what's the view of people who have used them on well tuned engines? My hunch is that the "creep" inherent in the design is a problem at higher performance but I'd welcome advice.

Thanks

Charles

Re: Crankcase - block gaskets

Charles,
I can't answer your question, but I've used one of these gaskets on the box saloon (1.5in pressure crank) it gets some stick and there's no leaks. Like you though , I'd be wary of a highly tuned engine. I'd stay with lecture if I were you. I do for those engines.

Re: Crankcase - block gaskets

Why does spell check interpret loctite which I spelled correctly as lecture? I despair of computers.

Re: Crankcase - block gaskets

Hi Charles,
I have become a bit of a convert recently having previously been a Loctite only fan. I have now put about 4000 hard leak free miles onto my Nippy after fitting a silicone gasket, however I have yet to finish rebuilding the special so can not comment on a really high revving engine. I was concerned that the creep and potential give in the casket may promote stud failure, but that so far is not appearing to be the case.
I would also be extremely interested to hear others experiences, I know Ruairidh has used them with success, perhaps he will add some pearls to this thread.

Location: NZ

Re: Crankcase - block gaskets

I don't build racing engines.

I have now fitted around 20 to standard engines however, they work perfectly - in my experience.

Credit must go to Doug Baker for this idea - he was brave enough to try it and share his experiences. I am very grateful he decided to "go for it".

Re: Crankcase - block gaskets

Thanks chaps.

I have no doubt that they're great in standard engines (thanks R) but it appears that nobody has been brave enough to use one in an "extreme" engine (either blown or high reving/power).
Given that Alan and Ian, both chaps who's engineering knowledge I respect, share my concerns about a compressible gasket being a weakness I'll probably stick wth 515 unless someone who has actually used one in extremis comes forward.

Thanks

Charles

Re: Crankcase - block gaskets

Charles,

my point is that someone has to try it first - you are obviously tempted so why not just go for it?

Can I also ask, if the Loctite works for you, why are you looking to try something else?



Re: Crankcase - block gaskets

What I have done on the Bantam (most definitely not a racing engine) is
1. Stick a sheet of a fairly heavy grade of gasket material to the crankcase,using the block to hold it down. First punch holes for the studs of course.
2. Trim around the block with a craft knife, then lift the block off.
3. Trim around piston holes etc
4. Trim back the gasket sheet by about 5mm all around the perimeter.
5. Apply a thin bead of appropriate grade silicone all around the perimeter.
6. Replace the block and loosely fit the nuts, then wait for the silicone to cure.
7. Tighten the nuts. (I usually wait several days before doing this).

That's how I skin the proverbial cat. It works fine and practically no cost. The tin baffles would complicate things of course but Bantam doesn't have them, fortunately.

Ivan

Location: Wellington, NZ

Re: Crankcase - block gaskets

Ruairidh Dunford
Charles,

my point is that someone has to try it first - you are obviously tempted so why not just go for it?

Can I also ask, if the Loctite works for you, why are you looking to try something else?



First mover disadvantage puts me off, especially with the thoughts about creep.
However I'm always looking for better ways, hence my curiousity. I'd just prefer not to remove the block again. It's bloody awkward with the blower!

Charles

Re: Crankcase - block gaskets

If it helps persuade you to try Charles, my Nippy runs the correct engine together with 9E77 cam etc, so the loads are probably fairly high, certainly far greater than your usual road engine...... I also have a rather heavy right foot
I will be experimenting with one of these gaskets in my special once I finally get the thing back together again, however I have been rather dragging my heels on this front recently.

Location: NZ