Fitting Core Plugs

[Mad Mart]

I have a couple of core plugs to fit to a Sprint block. One of the few jobs I've never done before. I've watched a few vids and some say to use a sealant and others say fit them dry. I'm sure a few of you have done this many times and can enlighten me.

[soe8m]

Sealant but the next reply will be dry.

Jeroen

[Carledo]

If you say so Jeroen! I've always fitted them dry and never had any trouble.

Steve

[Mad Mart]

Sealant but the next reply will be dry.

Jeroen

You must be psychic Jeroen!

Thanks guys. So using sealant is belt & braces.

[Carledo]

The main reason I don't use sealant (apart from that was how I was taught as an apprentice, too many years ago to think about) is that I don't like the idea of excess blobs of silicone floating around in the water jacket and maybe blocking something important. Yes you will be careful, but why risk it when they will seal perfectly well dry?

Steve

[soe8m]

I do not have blobs when using sealant. One of the worst inventions was silicone sealant. Never used it only because the look of it. I use different sealants for different surfaces and materials and how to seal. Core plugs I use a loctite flange sealant. Very thin and hardens when the oxigen is gone. Yes you can leave the tube open. There's no blobs just a sealant that prevents little seeping by damaged or rusty surfaces. Might there be an excess it flushes away because it does not harden. Only the contact area of the materials. This type of sealant goes also between the oil pump and block etc.

No silicone for me.

Jeroen

[Jon Tilson]

Like Steve I dont use sealant on core plugs.
New ones should be plated so dont rust (well for 30 years or so anyway).
Obviously clean the holes so the surfaces are smooth and corrosion free.
The hard bit is getting them in. I tend to go for a smear of copaslip on the plug rim to ease entry.
Then smack squarely pretty hard with a lump of wood against the plug and a lump hammer.

Not the nicest of jobs...



Jonners

[Carledo]

A lot easier with the block on the floor! I've changed too many with the engine in situ over the years, that really ISN'T fun. Nowadays, on the few engines I rebuild, I check all the core plugs as a matter of course and replace any that are even remotely suspect. A stitch in time saves nine, trite but true!

Steve

[James467]

Loctite do a sealant specifically for core plugs Mart, I'll look it up on my data sheet for you when I'm back if you like.

J