Strange noise from the engine
 

Just put the baby in the garage, turned the motor off, and heard a strange popping noise. I do have oil leaks (hence going back in and redoing everything when I get settled) but this was a "boiling and popping" sound from inside the motor. The sound was not oil boiling on the exchangers. I checked that out first... I am using 1 quart to 250 miles and it is all leaked. 2800 miles from the re-build. Engine temperature below normal. Outside temperature in high 60's. O2 sensor disconnected yesterday to solve idle issues, idling at 950. Oil near top mark of dipstick, 40 mile jaunt from work to home. '83 SC, US Spec, normal aspiration, factory spec with updates. Thanks,

Can you be a little more specific about the sound? A crackling noise is common as the engine contracts after being shut off. A gurgling noise could be oil movement, but it's hard to tell from your description if this is what you are talking about.

I will try. It sounded like bacon frying. I have not noticed this sound before.

Mmmmmmm.......b-a-c-o-n!

You have 2800 miles a on a rebuild and are using a qt. per 250 miles?!?!?!? Whether it's leaking or burning, you have a problem. It also sounds like you're overfilled. Oil level needs to be at midpoint between tick marks on dipstick when at full operating temp.

Uhuu, that's a lot of leaks for a recently rebuild engine. Would you mind sharing with us who did that rebuild. It wasn't by any chance the wordlfamous shop in southern California AKA MM?

In any care, if you did not do it yourself I would be all over the guy, who did it.

Ingo

Question, did the noise start after you disconnect to O sensor.

Dave,
I think you put too much oil. I have a 3.0 with 2300 miles
on rebuilt, and I haven't added any oil yet. When hot, around
140 deg, oil is at 1/4 inch above bottom mark. As long as
oil qty gage is above red zone at idle, I don't mind. Of coarse
at crusing speed, qty in below red zone.

Any moisture in the oil can cause that to happen. When the car sits you can get condensation inside the motor or oil tank. If it is cold enough that it didn't get up to boiling temperature then I would suspect that the heat soak after the motor is shut off could cause something like that.

I used to see something like that happen when the temperature was below 10 degrees and I wasn't driving it regularly. (American V-8 though...) Unless it repeats I wouldn't worry.


Wayne

was it raining?

the cooling (exhaust system and exchangers) tends to produce that noise, more so if its wet under there.

Let's see if I can address:

The rebuild was done by the idiot behind the wheel and his father-in-law. I since discovered that the two "calibrated" torque wrenches used were not in spec. One was high, one was low. I am not burning an ounce of oil, but there are leaks. I need to take the motor back out and re-seal and check torque on everything. Since I am in the process of trying to move I do not have anywhere to set up for two months and effect repairs. I maintain the oil above the bottom mark and only add when the level hits the bottom mark on a warm engine.

And Doug, I am eating bacon this morning in light of your thoughts!! MMMMMM

Studog, the noise did start after disconnecting the O2 sensor. But did not happen yesterday morning nor this morning. I will be listening for it after I get home tonight.

There was no rain, but high humidity.

Wayne, you might be onto something. I might have collected humidity after the morning drive in the fog and it sat all day without much burn-off.

Thanks yall. I feel a little better about the bacon sound. And now: BACON!! MMMMMM

Drive home was fine. Temperature about 10 degrees colder today and the humidity this AM was not near as high. I did not hear any "bacon" sounds after getting home. Maybe the humidity collected in the engine and burned off during/after the ride home?

Doug: Darn you; I still want more bacon now!

Check if the noise is coming from the oil tank, I have a freind with a 914/6 that make noises like that from the oil tank onece the motor is shut down. I think there are some valves in there that can make a funny noise.