Sealant or not on old NOS fiber gaskets?

[Sam M.]

I have a few things to add on to what JACQUES said.

There are different kinds and different thicknesses of gasket material.  You want some that can resist fuel, oil and water.  There is a blue type that I was told is for radiators and won’t be suitable.  Common types are paper and cork, but there is also a rubber type that can work too.  Paper type is most often used.  I find that not all paper types are created equal as the brand I currently have tends to make loose fuzzy pieces when I cut tight corners with it (which you do not want getting into the engine).  Seems to be an uncommon problem though.  Cork gasket material tends to only get used for certain things, like pressure tank gaskets.  (All of the motors in your list except for the Johnson 2.5hp and the McCullochs were designed to run on a remote pressure tank.)  For home-made cylinder heads, I’m pretty sure there is gasket material with a metal core that can work.

It’s good to have your new gasket material’s thickness close to the original’s thickness so parts fit properly.  I recall reading (probably in the AOMCI Current Projects section) that someone discovered the new powerhead base gasket they had tried to use was too thin because the driveshaft was pushing up on the crankshaft and putting excess pressure on the bearings.  You don’t want that.  Also, if your new thickness is really different, you may need to adjust your shift linkage to compensate, however as of now, I have not needed to adjust any shift linkage so I don’t know if it is that sensitive.

I agree that if a cork float’s coating is not peeling, there is no need to sand or refinish it.

There are 2 main types of spark plug wire.  The “solid” type of spark plug wire JACQUES mentionned on page 2 is the copper type.  The other type (without copper) is for electronic ignition.  You want the copper-core wire for your points and condensor ignition systems.

[Sam M.]

Stewart, I added a reply to add onto what JACQUES said, but when I did a tiny edit on it (after it was posted) it disappeared.  This has happened to me before and the post reappeared within a few days.  If it does not reappear, I can rewrite it.  In the meantime, just don’t buy any non-returnable sky blue gasket paper or any that has a notably different thickness from your NOS material.  Also, if you decide to buy new spark plug wires (many collectors like to, but it’s not always needed), make sure they have a copper core for points and condenser ignition systems.

[JACQUES]

A good read  for students is the excellent series of articles by m.Mohat posted in the western region AOMCI site..

explains magnetos, condenser &  repairs  etc… very educational  series 1-4,   the magic of magnetos, Mercury phase maker ignition etc…

all downloadable..

it even has a great article on testing condensers with his home made test box .. I built the basic  version and it work real good with a simple go-no go  lamp …

 

just write to m. mohat  for his  circuit drawing if he is available (haven’t seen him here in a while)   if not I  hava a copy.

Magazine Articles | Western Reserve Chapter

 

Joining AOMCI has priviledges 🙂

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