How Do I Clean the Inside of an F.I. Plenum?

[Monte M.]

I need a little help with a way to remove the carbon and or whatever else is on the inside of a plenum. I do not want to put it in the bead blaster as it might change the surface. It is a really early 1963 sand cast plenum.

I have cleaned a number of plenums over the years, but have never seen one with so much build up. Can anyone tell me if this is normal, or have I just been lucky with the units I have had. Maybe backfiring sending fuel back into the plenum to burn and leave residue was the cause.

This is a very rare plenum, so not changing the surface texture, or leaving it stained, is very important. I did a similar plenum about a year and a half ago and had no problem at all. But, this one is a much bigger mess.

Any ideas would be appreciated. I have tried, of coures "Dawn", some light solvents, standard cleaners and a number of other things. I even used to use oven cleaner when I was a kid, but there has to be something better out there.

Again, this is a rare sand cast plenum, so it is much more porous than a die cast plenum. The other one had so little build up, it came off without much trouble. This one is going to be a different beast.

Thanks for checking in.

[Clem Z.]

Re: How Do I Clean the Inside of an F.I. Plenum?

I need a little help with a way to remove the carbon and or whatever else is on the inside of a plenum. I do not want to put it in the bead blaster as it might change the surface. It is a really early 1963 sand cast plenum.

I have cleaned a number of plenums over the years, but have never seen one with so much build up. Can anyone tell me if this is normal, or have I just been lucky with the units I have had. Maybe backfiring sending fuel back into the plenum to burn and leave residue was the cause.

This is a very rare plenum, so not changing the surface texture, or leaving it stained, is very important. I did a similar plenum about a year and a half ago and had no problem at all. But, this one is a much bigger mess.

Any ideas would be appreciated. I have tried, of coures "Dawn", some light solvents, standard cleaners and a number of other things. I even used to use oven cleaner when I was a kid, but there has to be something better out there.

Again, this is a rare sand cast plenum, so it is much more porous than a die cast plenum. The other one had so little build up, it came off without much trouble. This one is going to be a different beast.

Thanks for checking in.

use spray choke and carb cleaner and then finish off with brake cleaner. since you are cleaning the inside what is the concern about the finish ????

[Monte M.]

Re: How Do I Clean the Inside of an F.I. Plenum?

use spray choke and carb cleaner and then finish off with brake cleaner. since you are cleaning the inside what is the concern about the finish ????

Clem,
The fact that there are very few of these sand cast units around, I want to keep it as original as possible. If there is a way to get this mess off of it without changing the finish, that is what I would like to do.

Yes, I know it is the inside, but I always try to do the least damage to a part as possible, be it the back side, the inside, or whatever. I just like trying to do it as correct as possible. It is just like painting the back side of a part even though you cannot see it.

Who knows, maybe in ten years someone will find that they were stamping something of value on the inside, but I will never know what mine said because I can no longer read it now.

Thanks for the input,
Monte