Removing old gaskets

[SIKMA]

Hi everyone,

I was rebuilding an engine the other day and had to remove old stubborn gaskets on manifolds etc, using a bench grinder with a wire wheel attachment.

Just wondering, by using the wire wheel attachment, its inevitable to slightly round off the edges of manifolds, will this affect anything? Also burn marks from the removal of the gaskets are evident from the friction between the wheel and surface, do the burn marks need to be further machined off or removed to enable a better contact area with the new gasket?

Cheers, Tommy

[GLANT]

I use a razor blade( be gentle on cast alloy though).... wire brush in my opinion is "rough" the sealing faces are delicate!
Yes!! it most definitely will round the edge, it also can cause highs and lows in sealing faces.
The reason "they" do it like that.. is time...it takes a little more time to hand scrape it with a razor...

hmmmm.. makes me wonder..if you took a $1000 V8 manifold to this bloke, would he wire brush it??

[geezer101]

Wire wheeling an old gasket off alloy is a big no-no. Either on a head or a manifold. Most machine shops haven't got a mill that can work on small areas like the carby mounting surface. If you're removing old gaskets from this stuff, use a spray on gasket solvent or even a cheap spray on foaming mag wheel cleaner to help. Patience pays when doing a job like this!

[astronturbo77]

just use a razor blade, this is all i do at work. or some emery on a flat steel block.

[SIKMA]

Cheers for the replys.

A razor is definitely the first step to remove the old gasket, I suppose some shops just want to save some money so they go the wire brush way to remove the hard bits of the gasket to save on gasket remover solvent. The theory with the highs and lows is a good point, however I dont know if it will really make an impact in the long run (i mean the mechanic would be really dumb if he really dug in with the wire wheel lol).

Are most japanese engines iron/alluminium/alloy heads?

I think the type of wire wheel aswell as the material of the metal comes into the equation too.

[davetrees]

Prepsol/Grease&Wax Remover works a treat for softening old gasket material enough to scrape off easily with a blade.... and the fumes are a bit less horrendous than carby cleaner !

Nylon scouring pads work well for tough bits too ..... abrasive enough to remove gasket material once softened, but not so harsh they will scratch the metal