Table spoon of oil found up in intake manifold in 3.2 Carrera...what does it mean...?
 

Howdy-

Took the intake manifolds off my 3.2 to clean a few things up again and get at the injector fuel lines I am replacing among other tasks. Here's the deal: when I removed the intakes there was a good tablespoon of motor oil sitting in the bottom of the intakes (underneath where the throttle body sits). Not sure what this means... or what it means about my heads.

Here's what I know:

-My engine has unknown mileage, and may very well have been rebuilt or touched up once before.
-It runs quite well, probably goes through a quart every 800-1000 miles, a little more under autocross type situtations. The last event of the year I popped the rev limiter twice during each run in first gear, so it saw some pretty high revs for its last use before winter storage.
-My plugs look normal after 3000 mi.
-I know I need to adjust my valves as they are noisy, and my reputable shop told me they were noisy- I needed to do them again- they said I didn't do them right (I agree).
-I am running brand new injectors.
-The exhaust valves were very white, but I'm not suprised as the fuel pressure regulator was bunk, and putting the car in a very lean condition (hard starts, etc.)
-The car does not smoke on startup, or belch any clouds away from a stoplight.
-The compression numbers done by the PPI shop about 3500 miles ago are as follows:

#1-160
#2-165
#3-160
#4-165
#5-170
#6-170

I've included pics of cylinders 2 and 5, they are about what the rest of the intake valves look like. What can you tell me about what you see?

Thanks-
BG

Cylinder 2:

http://forums.pelicanparts.com/uploa...1073268006.jpg

Cylinder 5:

http://forums.pelicanparts.com/uploa...1073268271.jpg

It sounds like you go some oil in from the breather. This can happen if there is too much oil in the tank or maybe from too much blow by from the rings. With your oil consuption and lack of smoke I would just clean it up and not run the oil level too high. The intake deposits don't look bad to me but I haven't seen alot to compare with. Drive the crap out of it for another 50k miles.

-Andy

I agree with Andy, could be as simple as too much oil added, and it's blowing through the breather (or oil foaming/bad separation). Could also be some slight leaking around the intake valves, but a teaspoon seems excessive to be leaking past the guides.

Those valves look fine to me, and I don't see the amount of oil you are referring too...

I've read this post now four times over the past day, and I'm still confused about where the oil was?

-Wayne

The oil was basically sitting in the driver's side intake, below the throttle body, just left of the rubber boot clamp that holds the two intakes together. When I pulled the intake barrel nuts off and undid the boot, upon seperating the intakes to weasel them off the top of the engine, the boot was wet inside with oil.

http://forums.pelicanparts.com/uploa...1073310445.jpg

Only place it could come from would be the breather. I wouldn't worry about it. As to the valves, they look completely normal.

Those intakes are way too clean Brian. ;)
-Chris

What Kurt said.

The valves look great. The oil is coming in through the breather hoses. Be sure your oil level isn't too high.

Breather - don't worry about it - it's normal.

-Wayne

hey BG,
how did you get that manifold so clean ??

Thanks for the info guys...

Manifolds and valve covers were bead blasted with 70/140 glass beads. They will get dirty fast once run again on the engine (as they are exposed aluminum), I'm deciding how to remedy that next...

The american V8 crowd seals their Al intakes with a clear coat. Write me a PM, I can find the info for you if you wish. In the long run however, if you want a nicely detailed engine compartment, there is only two ways:

1. Work it with the tooth brush every weekend.
2. Don't drive it.

Both options are not for me. I am happy if nothing leaks...

George

I've got a set of 3.2 manifold I'm going to have blasted. I'll probably paint it with some clear coat engine paint in an attempt to keep it looking nice...

-Wayne

I am a big fan of Motronic 3.2L engines. What you are experiencing is an oil draw into the manifold coming from the often- wide open throttle situation you are experiencing during your autocross days( a couple rev limit hits are harmless-even a boatload are harmless)l. All late carreras have a vacume limiter type cone in the line going form the oil tank breather in the neck of the oil tank to the air intake just above the throttle body. It is locate about 4" from the oil tank neck. Make sure that part is in the system and faces with the cone pointing toward the oil tank. All older cars should work these into the system and many 3.0's have something that accomplishes this same task before the local wrench replaces the line and doesn't put it back in the system.

When this crankcase pressure-oil tank pressure,intake draw condition happens the engine is sucking the oil filled vapor into the engine, mixing with the intake air and the fuel- Guess what all that hot oil filled vapor does to the octane rating of the fuel? You got it- downward spiral of heat, low actane, detonation.... We race in 100+ F ambient temps here in Ca sadly and I have seen these motors give up from this many times-there is no safety. Best thing is to add a breather bottle for the oil tank(look at pic's of an early RSR) and plug the back of the intake, this way you incorporate far more safety into the system. I have pic's if you need them just email me- no PM nonsense.

The pic's of the intake are no help as the gasoline that washed that port conatantly keeps anything from building up. I have seen exhaust ports say 25 % restricted with consumed oil and carbon from shot guides and the intake ports,valves, guides, looked as you depict.

Do a leakdown- this will tell you what is going where. The stk valve guides are shiatzsu.

Lastly- never run your engine on the track more than 1/2 way between the two oil marks on the dipstk at full temp- say 190F.

Kevin Roush
GAS Motorsport
Performance Porsche
Upland Ca
909 985 2909
Kroush2001@aol.com

I too found that oil in my intake when I had it off once. I cleaned it out with carb cleaner and a brush. Could this also occur from overfilling the tank during an oil change? That is, adding all the oil (say 10.5 qts) instead of adding some and then topping off after reaching operating temp? I usually add 8 and then top it off once warm.

VHT clear should be good for those intake manifolds.

I thought I was mistaken last time the guide issue was brought up, but Kevin's mention of the exhaust valves being more contaminated makes me think otherwise. I could swear the exhaust were the bad guys. So, if you're concerned about your valve guides? Check the exhaust ports! If your leakdown checks out good, a can of Berryman B12 Chemtool in the tank does wonders for cleaning up those ports. Worked awesome in one applicaton on my motor.