To give some background I bought this FD in late September. Living in upstate NY I saw no reason to register the car before having to keep it in the garage for 5 months and have not driven the car since buying it. Since buying the car I’ve changed all fluids and filters and I premix .5oz/gallon. I start the car up once a week and let it idle for about 10 minutes rev the car almost to redline to clear out any carbon deposits and then park it until the next week. Today upon my routine checking of fluids I saw what appears to be moisture in my oil fill neck. The coolant looks fine and the level appears to have stayed the same. The oil does not smell sweet. Any input? I apologize for being such a novice rotary owner but I want to take care of the car as good as I possibly can.

 

As far as I know, some white goop at the top of the filler neck is not uncommon.

Some condensation can get in there and mix with the oil.

Others may have a different opinion.

Overtime the oil cap seal will become brittle. Best replace. It may become hard to remove the cap.


I see a breather hose going to the PCV valve.

There should be a "T" in that line with a second breather hose running to the front Turbo intake elbow.

Often that hose gets deleted (as does the one to the PCV valve.)

People often run the breather hose to a aftermarket catch can.

As you are aware, overfilling the oil above the half way mark of the hashmarks on the dipstick might result in oil rising up and into the breather hoses.

No bueno.

That green check valve in your picture may break very easy.

Look into replacing it if it is not new already,.

 

Agreed. It looks like a little water/oil emulsion. Based on your post and in my experience it’s pretty common in cooler weather. You start and run the car for brief periods which causes a bit of condensation each time. It gets mixed with a little oil and settles around the oil cap.
If you were able to let it run at full operating temperature long enough that water vapor would eventually go away. Sometimes if the oil is older and dirtier (darker) you get something resembling baby poop. I think that’s all you’re seeing, and no big deal.

And kudos to changing those fluids on a new-to-you car.

 

Thank you for both of your input. Gives me some peace of mind my head immediately went to blown coolant seals. I will replace the oil cap check pcv valve and check valves and change the oil. Thanks again!

 

If the engine bay has been undisturbed for 30 years, best study up before diving in too deep.

Understand what will break, before you start breaking things.

You can run through a series of tests before you even pick up a wrench, that will give you an idea of what may need attention first..

In any event, have a contigency reserve of about $3000 in case you get into a cascading issues as you move around the engine bay chasing issues.

This assumes you replace all vacuum tubes, solenoids and (many of the) sensors with OEM.

 

https://www.rx7club.com/3rd-generati...k-off-1140942/

 

You can always send an oil sample to Blackstone Laboratory (https://www.blackstone-labs.com/) for chemical analysis.

 

Not enough data to really make a conclusion. Sure, condensation and emulsified gross in the oil filler tube isn't good, but it also doesn't mean much unless it's contaminated the sump.

 

JMO, but with my 30 year old, I only start it when I drive it. And then I drive 15-20 miles to get it hot and vaporize any condensation. When I park it (garaged), open the hood to vent all that hot air and disconnect the battery with one of those quick disconnects with the ****. Then when the season's over, I fill the tank (Stabil) and cover it up and leave it until Spring. Unless, of course, I go out there in the Winter and peek, admiring my good taste...

 

In cold weather I always get some of that. It's absolutely normal and nothing to worry about. I have sometimes wiped it off, but that's just being compulsive.

 

the RX8 had a Mazda TSB for it, same condensation issue.
.

 

So what did they say to do to remedy it?

 

its been a while, but there was a thing to wipe the dipstick off..

IRL, you change the oil and let the car warm up when you drive it, and it won't do it

 

in 2006 they added an additional larger tube connection at the base of the oil fill pipe where it bolts onto the center iron flange and ran another hose to the air intake tube. The original connection/hose is still there at the top of the fill pipe just under the oil fill cap. Whether that resolved it or not I can’t say. I had a 2005, but never had the issue.

There’s not really much you can do in certain circumstances regardless. Everything has to get warmed up to temp long enough to cook off the moisture. Just cranking it up and letting it idle for 5-10 minutes may not be sufficient. It might be more like 20-30 minutes depending on the conditions. Which the hood should be closed etc. to built up as much heat as possible is all I can suggest.

it wasn’t just the dipstick though. The oil fill is basically the same as the FD, just oriented different and serves as a mounting/support point for the Nylon UIM to suit the Renesis. The goo could be found up in the top section as well looking in from the oil cap opening.
.

 

That doesn't help eliminate the whitish crud in the filler tube, which is the only place I've seen it. So maybe the RX8 had not quite the same issues with this.

TeamRX8's reply clarifies the RX8 recommendation.

 

It’s an age-old issue. I have an early 50’s Chevrolet, built before they ever heard of a PCV . Just a vented oil fill cap and rocker cover. Still, if I back it out of my shop once or twice during the winter I’ll see baby-stool start to collect. It’s harmless.

I mean no offense, but you know its spring when these threads really start up with newer owners.

 

^spring and fall is when it typically happens with the big change in temperature

Totally normal, @pspecd Wipe it off and take the car for a nice drive.

 

here is the text of the Bulletin Team mentions. i'm a little hazy because we only did a few of these, like three, and it was 20 years ago


the 2006+ Rx8's basically had this update from the factory. basically if one wants a 2004-2005 Rx8, step one is to do all the updates to bring it to the 2006+ spec. its a lot too