A dead cat and oil in teh exhaust

**Biggo** · 13-07-2007, 02:30 PM

Hi all. After finally managing to fix my 20v due to a blocked cat. Im trying to figure out just why/how it died so i dont do it to my next one. The car has been sitting for about a month and bout 2 weeks ago i wen to start it. LOTS of condensation resulted. As i dont have a license i didnt drive it at that time so it only got warmed up. Anyway a few days ago i took it out for a quick strap around the block. More condenstaion and low temps resulted.

Now i have just installed a free flow oil cooler and as i havent had it at highway temp i havent been able to level the oil in the sump. But i did top it up with another liter to be sure (befor driving). The problem is how did my cat die? Was it oil? If so how did it get into the exhaust? As there was a fair amount in there. I am using a gen 3 monaro cat.

Any ideas? I dont want to blow more money again...

**oldcorollas** · 13-07-2007, 03:25 PM

first step.
how is it blocked? is it full of carbon? or has the guts of it collapsed/melted?
carbon is too rich mixture or oil.
collapsed/melted = too hot, whihc is usually a result of too rich mixture or oil

water is one of th emain products of combustion. condensation is just that moisture getting cold enough to form droplets of liquid.

low temps of what? engine? that is related to radiator, thermostat, and oil cooler.

there was lots of oil in your exhaust/cat? as in liquid oil?

only way for oil to get into exhaust is either from the combustion chamber or from the valve stem seals (with lots of crankcase air pressure)

unless the oil cooler somehoe returns oil to the exhaust pipe?

**stradlater** · 13-07-2007, 06:33 PM

Why is there a feline in your exhaust?

**The Real Roadrunner** · 13-07-2007, 06:50 PM

Originally Posted by stradlater

Why is there a feline in your exhaust?

i was just about to ask how a cat got in there and what type? ginger etc...

**lexsmaz** · 13-07-2007, 07:40 PM

Would have had to be one hot pussy ..............

**stradlater** · 13-07-2007, 07:45 PM

Hohohoh.... I'll bet your proud of that one mate... ;-)

**Biggo** · 13-07-2007, 08:29 PM

yair one hot pussy powers my car lol

nah i dunno, there is no crankcase bypass pressure, nor is there an inlet for oil in the exhaust manifold. Maybe the winter weather has something to do with it after all?? i regularly reaches 5 or less here so i dunno.

The next step is get a new cat and while im at it ill get this cannon thingy put on for shits and giggles....

**Biggo** · 13-07-2007, 08:30 PM

btw its a tabby cat

**oldcorollas** · 13-07-2007, 08:36 PM

well.. my car sees -15 and -20 and doesn't kill cats.. feline or otherwise.
winter has nothing to do with it.

how much oil is in the cat? is it actually oil? is it burnt oil?
if there is oil, your engine is rooted, and you need to fix it before you waste another cat.

cannon = no

**Biggo** · 13-07-2007, 08:41 PM

cannon = yair so i can shoot felines at passing motorists

burnt oil by the looks of the black mix dribbling onto the floor. I suspected the rings were rooted but it still pulls acceptable compression.

**oldcorollas** · 13-07-2007, 09:31 PM

past the rings should not give you liquid oil.

is the dribbling stuff "oily" to the touch? or just water mixed with carbon?

can you detect this oily stuff further up the exhaust? take off the manifold and see if it is from all ports?

do you have any crankcase ventilation? hasn't been blocked off?
valve stem wear etc? or no seals?