Toyota 3S-FE engine spark plug tube seals
Someone I know has this engine in a 1989 Celica ST and he is getting oil in at least one tube.
Is it likely that replacing the seals (I suggested doing all 4) will fix the issue, or could there be other problems which are causing the oil leakage?
I have never seen the engine, so I don't know what condition it is in or how many miles are on it. Most likely, it has a LOT of miles.
He wanted to do the seal replacement himself, but he is a complete auto-repair novice, so I suggested taking the car to a mechanic. Even a back-yard mechanic is likely to known far more than he does.
On the 3S-FE, the spark plug tubes are threaded into the cylinder head.
Most times if oil is in a tube, it is because the sealant on the threads has failed (as opposed to the rubber seal at the top).
It isn't really a DIY job for a novice. These tubes can at times be very difficult to remove.
Also, as shown in the large image at the center here ( »www.google.com/search?q=toyota+3···;598;800 ), there doesn't appear to be a lot of space between the tubes and the camshafts. If he damages a camshaft, this will cost him WAY MORE money to replace than he will ever save by avoiding using a mechanic.