Slow Guy

I'm in the process of replacing the SAI Check Valve and cleaning out the ports. I'm using the Hoppes (sp?) gun cleaning fluid as I believe that makes sense for this application. I won't be letting the fluid sit overnight as I think solvents left for extended periods may wind up caking up the small ports if left too long (JMHO).

After making up my fitting and hose I squirted 3-4 ozs. of Hoppes in my hose w/in a few seconds it was dripping from cyl's 4-6 (good sign), I had to apply the air hose to get anything to come out of the 1-3 cyls (makes sense to me) however, fluid flowed very well through cyls 1 & 2 but very little came out cyl. 3 (good thing I'm doing this project). I'm trying now to figure out a better way to plug the good flowing cyls. so I can get more flow to cyl 3, a DIY mentioned chewing gum, maybe I'll try that later.

Anyhow, to get to my question, I took photos of all 6 cyls. (exhaust ports) prior to running fluid through after noticing a glossy substance in 2 cyls. (2 & 6) near the valve stem port through the head (photos do a better job of showing what I'm talking about). I suspect this is oil seeping around the valve stem but would like input from those more knowledgeable than myself. Is this anything I should be concerned about or is it normal?

From my limited experience, overall the exhaust ports look ok, there's more carbon buildup than I would like (the car has 70K miles) so I'll plan on using something like Techron a little more frequently.

Again, car has 70K mi. and these photos were taken BEFORE any cleaner was used on the SAI system, this is how they looked after just dropping the heat exchangers.

Slow Guy

For comparison this is what cyl. 4 exhaust port looks like.

Slow Guy

No one?

Mike J

I had the same looking exhaust ports, some with the shiny black surface. The exhaust ports are ceramic coated on the 993, perhaps its a bit of oil that has been baked into the ceramic. I know its very hard and does not feel oily or anything. I think its nothing to worry about.

What is your oil consumption?

Cheers,

Mike

Slow Guy

Thanks Mike, oil consumption is next to nill, it stays at the mid-point between low and full until time for oil change.

It appears to me the glossy substance is on top of the carbon deposits, not on the metal with the carbon on top.

I'm not real concerned but I am very curious as to what it is and/or what causes it.